February 20th, 2015
The SPRI Library has a private collection of books for in-house use for research and working tools by employees of Sugar Processing Research Institute, Inc.
Journals in the SPRI library are, in addition to being useful to SPRI employees, for aid to SPRI’s paying members. Some of the journals are shown below. Not all years are included in the library.
To inquire, please email SPRI
American Chemical Society: Division of Fuel Chemistry, Proceedings
American Chemical Society: Division of Environmental Chemistry, Proceedings
American Chemical Society: Polymeric Materials Science and Engineering, Proceedings
American Society of Sugar Beet Technologists – Journal of Sugar Beet Research
American Society of Sugar Cane Technologists (ASSCT) Journals
American Society of Sugar Cane Technologists (ASSCT) Proceedings
The Australian Sugar Journal
Australian Society of Sugar Cane Technologists (ASSCT) Proceedings
Bone Char Research Project Inc., Technical Reports
British West India Sugar Technologists, Proceedings
Carbohydrate Chemistry, Journal of
Commission Internationale Technique de Sucrerie (C.I.T.S.) Proceedings
Copersucar, Annual Report
Euro – Carbohydrate Symposium, Proceedings
F.O. Lichts Yearbook
Hawaiian Sugar Technologists Reports
Hawaiian Sugar Planters’ Assn., Annual Report
Fiji Sugar Corporation Ltd.
Sugarcane Research Centre Annual Report
International Society of Sugar Cane Technologists (ISSCT), Proceedings
International Carbohydrate Symposium (ICS0, Proceedings
International Sugar Journal
La Sucrerie Belge
L’Industria Saccarifera Italiana
Mauritius Sugar Industry Research Institute, Annual Report
South African Sugar Assn. Experiment Station, Annual Report
South African Sugar Journal
South African Sugar Technologists (SASTA), Proceedings
Sugar Cane International: The Journal of Cane Agriculture
Sugar Y Azucar
Sugar y Azucar Yearbook
Sugar Industry Abstracts
Sugar Industry Technologists (S.I.T.) Proceedings
Sugar Milling Research Institute, Annual Report
Sugar Milling Research Institute, Literature Survey
Sugar Processing Research Institute, Inc., Conferences, Proceedings
Sugar Processing Research Institute, Inc., Workshops, Proceedings
Sugar Research Institute, (SRI), Annual Report
Sugar beet Research Report
Sugarcane Research (LSU AgCenter), Annual Report
Sugar and Sweetener: Situation and Outlook Yearbook
Sugar Technology Reviews
Tate & Lyle, Annual Report
Taiwan Sugar Research Institute, Report of
Taiwan Sugar Experiment Station, Annual Report
Technical Session on Bone Char, Proceedings
Technical Session on Cane Sugar Refining Research, Proceedings
Trends in Food Science & Technology
United States National Committee (USNC), Proceedings
United States Field Laboratory, Houma, Louisiana, Report
In addition to operating its research program, SPRI holds the Conference on Sugar Processing Research every second year, providing technical leaders in the sugar industry an opportunity to present their findings. Proceedings of these Conferences form a written record of advances in processing, new products and analytical methodology in the cane and beet sugar industries. Along with the Conference on Sugar Processing Research, SPRI also has hosted, on occasion, a Workshop on Sugar Processing Research, which is geared to technical and mill workers in the sugar industry.
Proceedings published thus far:
• Proceedings of the 2008 Conference on Sugar Processing Research, “Diversifying Research in Sugar Processing,” Delray Beach, Florida, USA, Electronic version only.
• Proceedings of the 2006 Conference on Sugar Processing Research, “Frontiers in Sugar Processing,” Águas de São Pedro, S.P., Brazil, Electronic version only.
• Proceedings of the 2004 Conference on Sugar Processing Research, “New Developments in the Sugar Processing,” Atlanta, GA, USA, April 4-7, 2004. (492 pages)
• Proceedings of the 2002 Conference on Sugar Processing Research, “Advances in the Chemistry and Processing of Beet and Cane Sugar,” New Orleans, LA, USA, March 10-13, 2002. (424 pages)
• Proceedings of the 2002 Workshop on Sugar Processing Research, “Future Directions for the Sugar and Allied Industires,” New Orleans, LA, USA, March 14-15, 2002. (In press)
• Proceedings of the 2000 Conference on Sugar Processing Research, “What Do We Need to Do for the Twenty-First Century in Sugar Processing, “Porto, Portugal, April 9-12, 2000. (376 pages)
• Symposium: “Advance Technology for Raw Sugar and Cane and Beet Refined Sugar Production,” New Orleans, LA, USA, September 8-10, 1999. (389 pages)
• Proceedings of the 1998 Conference on Sugar Processing Research, Savannah, GA, USA, March 22-25, 1998. (554 pages)
• Proceedings of the 1998 Workshop on Sugar Processing Research, “Sugar Around The World: Products and End Uses, Quantity and Quality,” Savannah, GA, USA, March 26-27, 1998. (Not published)
• Proceedings of the 1996 Conference on Sugar Processing Research, New Orleans, LA, USA, April 14-17, 1996. (534 pages)
• Proceedings of the 1996 Workshop on Sugar Processing Research, “Separation Processes in the Sugar Industry,” Savannah, GA, USA, March 18-19, 1996. (299 pages)
• Proceedings of the 1994 Conference on Sugar Processing Research, Helsinki, Finland, August 7-9, 1994. (396 pages)
• Proceedings of the 1994 Workshop on Sugar Processing Research, “Products of Sugar beet and Sugarcane,” Helsinki, Finland, August 10-11, 1994. (307 pages)
• Proceedings of the 1992 Conference on Sugar Processing Research, New Orleans, LA, USA, September 27-29, 1992. (371 pages)
• Proceedings of the 1992 Workshop on Sugar Processing Research, “Analysis of Sugars in Foods,” New Orleans, LA, USA, September 30, 1992. (167 pages)
• Symposium: The Division of Carbohydrate Chemistry of the ACS, “Carbohydrates in Industrial Synthesis,” 1991. (111 pages)
• Proceedings of the 1990 Conference on Sugar Processing Research, San Francisco, CA, USA, May 29 – June 1, 1990. (443 pages)
• Proceedings of the 1988 Conference on Sugar Processing Research, New Orleans, LA, USA, September 25-27, 1988. (341 pages)
• Proceedings of the 1988 Workshop on Sugar Processing Research, “Raw Sugar Quality and White Sugar Quality,” New Orleans, LA, USA, September 28-29, 1988. (173 pages)
• Proceedings of the 1986 Conference on Sugar Processing Research, Savannah, GA, USA, October 19-21, 1986. (389 pages)
• Proceedings of the 1986 Workshop on Sugar Processing Research, “Workshop on Raw Sugar Quality: Present and Future,” Savannah, GA, USA, October 22, 1986. (108 pages)
• Proceedings of the 1984 Conference on Sugar Processing Research, New Orleans, LA, USA, October 16-18, 1984. (378 pages)
• Proceedings of the 1984 Workshop on Sugar Processing Research, “The International Dextran Workshop,” October 19, 1984. (90 pages)
• Proceedings of the 1982 Conference on Sugar Processing Research, Atlanta, GA, USA, April 29 – May 1, 1982. (272 pages)
• Proceedings of the 1980 Technical Session on Cane Sugar Refining Research, New Orleans, LA, USA, October 19-21, 1980. (229 pages)
• Proceedings of the 1978 Technical Session on Cane Sugar Refining Research, Washington, DC, USA, September 17-19, 1978. (205 pages)
• Proceedings of the 1976 Technical Session on Cane Sugar Refining Research, New Orleans, LA, USA, January 23-25, 1977. (226 pages)
• Proceedings of the 1974 Technical Session on Cane Sugar Refining Research, Cherry Hill, NJ, USA, October 20-22, 1974. (154 pages)
• Proceedings of the 1972 Technical Session on Cane Sugar Refining Research, New Orleans, LA, USA, November 13-14, 1972. (103 pages)
• Proceedings of the 1970 Technical Session on Cane Sugar Refining Research, Boston, MA, USA, October 12-13, 1970. (193 pages)
• Proceedings of the 1968 Technical Session on Cane Sugar Refining Research, San Francisco, CA, USA, September 30 – October 1, 1968. (162 pages)
• Proceedings of the 1966 Technical Session on Cane Sugar Refining Research, New Orleans, LA, USA, October 1O-1l, 1966. (153 pages)
• Proceedings of the 1964 Technical Session on Cane Sugar Refining Research, New Orleans, LA, USA, November 9-10, 1964. (86 pages)
• Proceedings of the 1961 7th Technical Session on Bone Char, Washington, DC, USA. (334 pages)
• Proceedings of the 1959 6th Technical Session on Bone Char, Montreal, Canada. (328 pages)
• Proceedings of the 1957 5th Technical Session on Bone Char, Washington, DC, USA. (336 pages)
• Proceedings of the 1955 4th Technical Session on Bone Char, Washington, DC, USA, May 5-6, 1955. (442 pages)
• Proceedings of the 1953 3rd Technical Session on Bone Char, New Orleans, LA, USA, February 26-27, 1953. (365 pages)
• Proceedings of the 1951 2nd Technical Session on Bone Char, Washington, DC, USA, May 3-4, 1951. (436 pages)
• Proceedings of the 1949 1st Technical Session on Bone Char, Washington, DC, USA, January 27-28, 1949. (321 pages)
SPRI has provided Technical Reports to its sponsors on various subjects over the years. Because SPRI sponsors have paid for this research, it is available only to them. However, abstracts are made available here.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI March 1965-No. 01
Molecular Weight of Soluble Polysaccharides in Cane Sugar
The soluble polysaccharides of cane sugar are part of the fraction commonly referred to as “gums.” These materials are found in all products from sugarcane to refined sugar. As a part of a continuing effort to further identify these commonly occurring sugar impurities, the molecular weight of several preparations was measured by light scattering. The molecular weight was determined to be in the range from one half to two million. Osmotic pressure measurements were not in disagreement with these values.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI October 1965-No. 02
Preparation and Properties of Psicose
Efforts to isolate and identify the “psicose” fraction of reducing sugars found in cane sugar products have not been entirely successful. Several preparations of “psicose” have been carried out and some properties of this sugar are reported.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI December 1965-No. 03
Observations of Phosphate Clarification
A study was made of the phosphate clarification process as it was found in commercial practice. Quantitative data are given for various constituents in liquors to and from the clarifiers and in the clarifier scums. It was observed that the amount of calcium phosphate in the scum was about equal to the amount of calcium and phosphate added, in the defecation of the liquors, with little net removal of calcium and phosphate from the sugar liquor. The scum contained roughly one half organic matter and appreciable quantities of magnesium and sulfate in addition to calcium phosphate.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1966-No. 04
Identification of Solid Phases in Clarifier Scums
Methods are given to identify the principal solid phases found in clarifier scums. The materials identified include quartz, aragonite, calcite, gypsum, anhydrite, starch, dicalcium phosphate dihydrate, dicalcium phosphate anhydrous, octacalcium phosphate, beta-tricalcium phosphate, and hydroxyapatite. Methods used in identification are: chemical analysis, X-ray diffraction, infrared spectra, petrographic microscopy and electron microscopy. Differential thermal analysis should also prove useful but in not included in this report. The principal basic calcium phosphate found in phosphate clarifier scums is octacalcium phosphate.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI March 1966-No. 05
Colorant Formation Under Clarifier Conditions
Colorant formation under refinery clarifier conditions was found to be primarily dependent upon temperature and pH, being much greater at high temperature and at high pH. None of the ionic constituents normally found in cane sugar liquors influenced the formation of colorant. No method other than lowering the pH was found that would decrease the color formation in heating alkaline sugar solutions.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI June 1966-No. 06
Identification of Some Sugars by Electrophoresis
The high voltage paper electrophoresis and its use in separating sugars is described. A system of internal standards greatly improves the identification of the separated material. The preparation of psicose by alkaline isomerization of invert has been shown also to yield allose, altrose, sorbose and tagatose in addition to mannose and psicose.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI July 1966-No. 07
Crystal Habit of Dicalcium Phosphate Dihydrate
The crystal structure of dicalcium phosphate dihydrate is described. The unit cell dimensions and position of the atoms are tabulated. The composition of the various crystallographic faces is shown in figures. The angle between the slow ray and the c axis is -17.2°.
The initial precipitate was always very fine. At low pH large crystals grew rapidly. At pH above 6 the precipitate remained fine and OCP was present. The crystal habit under various conditions of precipitation has been determined. The crystal always forms very thin tablets on the 010 face, with the usual edge faces being 121, 112, and 110. Low pH or the presence of sulfate produces the 221 face. The 011 face occurs after a long time and a vicinal face at the 6kl direction often replaces the 110 face at low pH.
The effect of various constituents of raw sugar upon the crystal habit was observed. Sulfate and aconitate markedly change the crystal habit but neither sucrose nor any of the other usual constituents have any effect.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\ SPRI September 1966-No. 08
Precipitation of Calcium Phosphate
The calcium phosphate precipitate was examined microscopically and the refractive index measured. Under refinery clarifier conditions, the precipitate was principally octacalcium phosphate at low phosphoric acid dosage but at high acid dosage an amorphous calcium phosphate was found.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1966 -No. 09
Physical Chemistry Problems in Sugar Processing
In applying the principles of physical chemistry to sugar processing conditions, one of the very fundamental and most perplexing problems is just how to take into account the great preponderance of sucrose. Corollary problems in the fields of activity, dielectric constant, ionic strength, ionic activity, ionizations, pH, pH scales, pH measurement, and solubility are discussed. Future progress in sugar technology will depend upon answering questions raised by these fundamental problems.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI December 1966-No. 10
A Yellow Component in Sugar Colorant
The separation of two yellow components in sugar colorant is described. The separation can be achieved by electrophoresis, alcohol extraction, or on a DEAE cellulose column. Several properties of one of the components are described but its identification in not yet complete.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1967-No. 11
A Yellow Cane Pigment Found in Sugar
The yellow colorant, C2, which is found in raw sugars has been shown to come from the sugarcane plant and not from sucrose decomposition. It has been identified as a substituted flavone of the apigenin series. IN the refinery it is removed from the sugar mostly by crystallization. It is also removed by bone char filtration and anion exchangers. It is not removed by phosphate clarification. Its specific absorption index per gram of colorant is about 150. It is estimated that typical light yellow liquors off char contain this colorant to the extent of 0.0007% of solids.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1968-No. 12
Fluorescent Sugar Constituents
A set of reference spot numbers is presented for cataloguing sugar colorants. Details of the electrophoretic separation and of the photographing of the spots are presented. The spots are described in sufficient detail so that other investigators should be able to identify the same spot with certainty.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1969-No. 13
Cane Pigments in Refining
As part of a systematic study of sugar colorants, methods have been devised to separate many cane pigment type colorants from the sucrose. These have been followed through the various refining processes and only a few of them carry through to the refined sugar.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI June 1969 -No. 14
Calcium Ion-selective Electrode
There has recently come on the market a series of calcium sensitive electrodes that are similar in some ways to the familiar glass electrode which is widely used in the sugar industry for measuring and controlling pH. Since calcium is an interesting constituent in commercial sugar liquors, these electrodes may possibly prove useful in measuring and controlling calcium.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI December 1970-No. 15
Identification of Sugar Colorants
For the first time ever, a number of cane sugar colorants have been identified. They are all cane pigments that escape the refining processes and some even persisting into the refined sugar. These are chlorogenic acid, caffeic acid, p-hydroxycinnamic acid, 4-hydroxy-3-methoxycinnamic acid, 4-hydroxy-3,5-dimethozycinnamic acid, kaempferol and umbelliferone.
Several additional constituents that are not colored have been identified. These are p-hydroxy-3-methoxybenzoic acid, 4-hydroxy-3,5-dimethoxybenzoic acid and 4-hydroxy-3-methoxybenzoic acid. Fumaric acid and aconitic acid, which were already known to be present in cane sugar have been located on the high-voltage paper electrophoresis separation of sugar constituents.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1971 – No. 16
Fluorescence of Sugars
A preliminary survey of fluorescence in sugar shows that it could possibly replace the color measurement. It is more sensitive that color in the low region and perhaps more informative. It is worthy of further study.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI February 1971-No. 17
The Effect of Solution Structure on Electrode Processes in Sucrose Solutions
Because of a history of anomalous behavior of electrodes in sugar solutions, the physical-chemical nature of the sucrose-water mixture was examined. The structure of the mixture could be explained by both the Frank-Evans and clathratehydrate theories. Theoretical activities were calculated from the measured composition by specially developed computer programs and compared with experimental activities, found by electrodes. Both the pH and calcium electrodes, in sucrose solution, read too low at high concentrations and too high at low concentrations: explanations for these anomalies were based on structured sucrose-water complexes in the electrical double layer around the electrodes. Various types of reference electrodes were compared in sucrose solutions, with respect to stability and reproducibility: those using 1M KCl showed greater stability that those with saturated KCl.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI August 1972-No. 18
Extraction of Minor Constituents From Sugar By Organic Solvents
A gas-liquid chromatographic survey of extracts of a raw sugar by several common organic solvents showed that all solvents extracted a large number of different compounds. Similar solvents extracted similar compounds, but different solvents extracted entirely different sets of compounds. No solvent was found that extracted only a very few compounds.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1972-No. 19
Plant Pigments as colorants in cane sugar
The subject of plant pigments as colorants in cane sugar is reviewed and the work of the Southern Regional Research Center (Agricultural Research Service) summarized. Most of the compounds so far identified are derivatives of benzoic acid, cinnamic acid, coumarin, and flavone. Only the compounds in the last three categories are actually colored, but all are considered colorants in the broader sense of minor constituents.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1973-No. 20
Gas Chromatography of Minor Constituents in Sugars
Progress in solving the problems related to measurement of minor constituents in sugars by gas liquid chromatography (GLC) is reported. The optimum GLC conditions have been determined and methods of obtaining the minor constituents free of the great excess of sucrose have been investigated. Four constituents have been identified in an extract from raw sugar and have been followed throughout the refining process.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI February 1973-No. 21
Fluorescence in Commercial Sugars
Instrumental Corrections were applied to fluorescence measurements in commercial sugars. The resulting corrected equal energy fluorescent spectra showed four principal peaks which were related to refining processes.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI April 1973-No. 22
Calcium Activity in Phosphate Precipitation
The activity of calcium ion was measured, with the calcium ion-selective electrode, in calcium phosphate precipitation processes in sugar solutions under varying conditions, approximating those of refinery clarifiers. A plot of critical ion activities was made, by computer, to determine nature of the precipitate. Results do not indicate any of the precipitates usually ascribed to this process.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI May 1973-No. 23
Heavy Metals in Cane Sugar Products I.
Levels of heavy metals of particular physiological interest have been determined by atomic absorption spectroscopy in raw and refined sugars and in various process liquors. Implications of these results, with regard to the effects of different refining processes on metal levels, are discussed. All metals analyzed for (Fe, Mn, Cu, Pb, Ag, Cr) are at levels well below any limits advised by regulatory agencies.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1973-No. 24
Constituents in Raw Sugar That Influence Refining
The present status in identification of the minor constituents in cane sugars and the effect of these constituents on refining is reviewed. The constituents discussed are ash constituents, including heavy metals, colorants, and floc constituents. Analytical methods for these minor constituents are described, and results show them to be in the ppm range in raw sugars and well below 1 ppm in refined sugars. There minor constituents will become even more important as standards for refined sugar are tightened and increasingly affect farmers, millers and refiners alike.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI May 1974-No. 25
Heavy Metals in Cane Sugar Products II.
Recent results from the continuing study on levels of heavy metals of physiological interest are presented. Samples of sugars and process liquors from various types of refining processes have been analyzed for these metals by atomic absorption spectroscopy. Results show that the levels of heavy metals were below recommended limits.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1974-No. 26
Color Precursors Formed in Sugar Under Acid Conditions
It has been shown that heating 50 Brix sucrose solutions at 85°C for five days produced 14 fluorescent compounds extractable with ethyl acetate. The most abundant of these was shown to be 3,4-dideoxyglucosulose-3-ene (DGU), the precursor to hydroxymethyl furfural (HMF). HMF is one of the immediate precursors to brown color and was found in small quantities in most refinery liquors tested.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1974-No. 27
Cane Sugar and Silicon
The role of silicon in cane sugar production are reviewed. Its effects on cane growth, inversion control and filtration are considered. The possible role of silicon in beverage floc formation is discussed.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI December 1974-No. 28
Determination of Lead, Cadmium, and Zinc in Sugar
A new technique for the elimination of the matrix interference encountered in the determination by flameless atomic absorption of lead, cadmium, and zinc in sugars is described. Yeast fermentation converts the sucrose to ethanol and carbon dioxide, both of which are easily volatilized. Very reproducible results for these elements are obtained using this technique.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI 1974-No. 29
Composition of Acid Beverage Floc
Acid beverage floc has been isolated from one sample of refined cane sugar and its composition has been studied. The major inorganic component was found to be silicon dioxide. The organic portion of the isolated floc consisted of polysaccharides and protein. The component sugars of the polysaccharides and the component amino acids were identified and quantitatively estimated.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1975-No. 30
Optimum Conditions for Determining Individual Minor Constituents in Cane Sugar By Gas-Liquid Chromatography
In measuring the minor constituents in commercials sugars, it is necessary first to separate the constituents from the large bulk of sucrose. This is best done by liquid-liquid extraction from a solution of the sugar. The optimum extraction conditions and subsequent gas-liquid chromatography conditions for several compounds have been evaluated and the resulting precision of the entire determination evaluated.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI March 1975-No. 31
Colorant Formation Under Refining Conditions
One type of colorant in commercial sugars is that formed in the course of refining processes. The literature on this subject is reviewed and current experimental work under controlled conditions is described.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI July 1975-No. 32
Composition of Soluble Indigenous Polysaccharides From Sugarcane
Sugarcane polysaccharides from freshly cut cane have been isolated and analyzed. These polysaccharides have a specific rotation of -46°compared to +30° — +160° for those isolated from commercial sugarcane products. Quantitative estimation of the component sugars resulting from hydrolysis of the cane polysaccharides indicated that galactose predominated, with arabinose, mannose, xylose, and glucose, in decreasing quantities. Polysaccharides of the arabinogalactan type may be implicated in floc formation.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI June 1975-No. 33
Some Observations on Acid Beverage Floc
The acid beverage floc-forming characteristics of six samples of refined sugar have been studied. All of the sugars contained an arabinogalactan, dextran, a small amount of starch and silicon compounds. Sugars in which the concentrations of arabinogalactan and soluble silicate are adequate form floc on acidification of their solutions. Floc formation is induced in some sugars with adequate arabinogalactan concentration by addition of a soluble silicate and in some other sugars with inadequate concentrations of arabinogalactan and soluble silicate by the addition of arabinogalactan (from sugarcane) and a soluble silicate. Floc formation in some sugars is inhibited by the presence of some types of dextran in the sugar. Floc formation is prevented also by filter aid filtration of the sugar at room temperature, or by cation or anion resin treatment. No conditions were found in which floc formation could be induced in the absence of sucrose.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI August 1976-No. 34
Soluble Silicates in Refinery Processes
A survey has been made of the effect of various refining steps on soluble silicate levels. The progress of soluble silicate has been traced throughout a refinery by analyses of sugars, process liquors, and process waters. Methods of analysis and particular problems with analysis of sugar samples are discussed. Implications of results on acid beverage floc formation and recycling of ash in process are considered.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1977-No. 35
The Role of Charged Colloids on Floc Formation
Further studies on the floc-causing factors in cane sugar have revealed that these substances are colloidal in nature. The electrostatic charges on these substances (polysaccharides and proteins) have been studied over a wide pH range. It was found that the negatively charged polysaccharides and the positively charged protein at low pH are key factors in floc formation.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI February 1977-No. 36
Determination of Refined Sugar Protein by Polyacrylamide Gel Electrophoresis
Polyacrylamide gel electrophoresis was found to be an excellent method of separating protein from the protein-polysaccharide complex that is implicated as a major factor in acid beverage floc. The protein in several raw and refined sugars was examined by this method. Progress in quantification of this protein is also reported.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI March 1977-No. 37
BAGASSE: A Review
This review of the nature, properties, treatment and uses of bagasse was requested by the Encyclopedia of Chemical Technology (John Wiley & Sons, Publishers) for their third edition, to be published in 1977. It was thought that the information in the review might be of interest to sponsors of the C.S.R.R.P. and so the article is herein reproduced as a Technical Report.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI May 1977-No. 38
Identification and Estimation of Glucuronic Acid in Indigenous Sugarcane Polysaccharide
Glucuronic acid has been identified and estimated in the indigenous polysaccharide from a variety of sugarcane products. The glucuronic acid content of the isolated polysaccharide ranges from 3% to 8.5% of polysaccharide. Galacturonic acid was not found in any of these products, indicating that pectin is not present in sugarcane.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI May 1977-No. 39
A Study of Sugar Inversion Losses by High Pressure Liquid Chromatography (HPLC)
Decomposition of sucrose to glucose and fructose accounts for some sucrose loss in processing. HPLC is used to follow sucrose decomposition under typical refinery condition ranges of temperature, pH, and concentration.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI October 1977-No. 40
Removal of Nondialyzable Sugarcane Polysaccharides in Refinery Processes
The total nondialyzable polysaccharide content of phosphatation and carbonatation refinery samples was determined by the phenol-sulfuric acid method. Major removal of polysaccharides occurs during affination and crystallization. Recycling of these impurities through the use of sweetwaters and blending of remelt liquors is demonstrated.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI November 1977-No. 41
Beverage Floc and Cane Sugar
The various types of organic, inorganic, and microbial flocs and hazes that appear in bottled beverages containing cane sugar are defined, differentiated, and discussed.
Acid beverage floc and its properties are considered in detail. Its isolation and analysis are described. The origins of acid beverage floc are reviewed, the discovery of sugarcane polysaccharides and protein components that cause floc formation is presented, and the floc-forming mechanism is explained. Floc tests and potential methods for prevention or removal of floc are discussed.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI July 1978-No. 42
Identification of Volatile Constituents Responsible for Characteristic Molasses Aroma
A method is described for direct elution and gas chromatography (GC) of low molecular weight molasses volatiles that avoids the necessity of solvent extraction. Volatile constituents were identified on the basis of GC retention time, peak enhancement, sensory evaluation, and mass spectrometry (MS). A number of constituents not previously reported in molasses were identified. It was found that dimethyl sulfide was a major contributing factor in the characteristic molasses odor. A total of 23 compounds were identified.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI July 1978-No. 43
Sugar Losses by Inversion
Inversion of sucrose to glucose and fructose accounts for some sucrose loss in processing. An analytical method has been developed using High Pressure Liquid Chromatography (HPLC) for direct determination of sucrose and invert sugar in aqueous solution. Results for inversion of concentrated sucrose solutions at 80°and 90°C and a range of pH are presented. Results are compared to work in the literature. Applications to refinery losses are discussed.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI July 1978-No. 44
Some Observations on the High Molecular Weight Colorants in Sugar
The high molecular weight colorants in raw sugar and the same sugar, washed, were separated by dialysis in bags with molecular weight cutoff values of 3,500, 8,000, and 12,000. The color in the original sugar and that retained in each bag was measured. The color from the washed raw sugar was compared to that of the raw sugar. The total nondialyzable materials from the raw and washed sugars were compared. The nondialyzable material from sugar was subjected to mild hydrolysis and yielded polyphenolic acids. The optical properties of the color in raw sugar and that in the same sugar after being washed were compared.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI 1979-No. 45
Sugar in Molasses
A high pressure liquid chromatography (HPLC) method developed for sucrose, glucose and fructose has been applied to a variety of molasses samples. Techniques for applying HPLC analysis to molasses are discussed. The results are compared to results by classical analytical methods. The observation that glucose/fructose ratios were frequently lass than unity is discussed.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1979-No. 46
Dextran Problems in Sugar Production
Dextran, composed of ά-1,6 linked polymer glucose sequences, is a major problem in the manufacture and refining of sugar from sugarcane. Dextran problems are primarily the result of processing partially deteriorated cane, but they can also be the result of poor housekeeping during processing. Refineries not only receive dextran occluded within the sugar crystal that cannot be removed by affination but they also re-circulate large quantities of sweeteners that are good media for dextran development. These problems are discussed, and selected data are included to show the magnitude of the dextran problem at several processing steps.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI May 1979-No. 47
Association of Low Molecular Weight Compounds with Sugar Colloids
The freeze-dried nondialyzable material from sugar was subjected to mild hydrolysis and three polyphenolic acids were identified in the hydrolyzate. Extraction of the freeze-dried nondialyzable material with ethanol desorbed a number of compounds, some of which were identified as sterols and color-forming degradation products of chlorophyll.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI August 1979-No. 48
Effect of Temperature Upon Filtration Efficiency
The effect of filtration temperature on the removal of colloidal materials from sugar liquors was studied. Liquors from selected stages in the refinery were filtered at temperature intervals of 10° from 25°C to 95°C. The high molecular weight material not removed by filtration at each temperature was determined. The implications of the results in the refining process are discussed.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI August 1979-No. 49
Review of Deterioration of Raw Cane Sugar in Storage
Literature review of optimum conditions for bulk storage of raw cane sugar, and the pol loss and color formation experienced over years of storage under various conditions. Two questions are answered: (1) what should be the storage conditions to minimize deterioration? And (2) what is the rate of deterioration under certain storage conditions?
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1980-No. 50
Sucrose Loss in the Manufacture of Cane Sugar
The loss of recoverable sucrose in sugarcane harvesting, raw sugar manufacture and sugar refining is a serious economic problem. Chemical and microbial destruction of sucrose begin sometimes even before harvesting, and continue through factory and refinery, and during storage of raw and refined sugars. In this report, the various causes of sucrose loss, including inversion, thermal destruction, alkaline degradation, and microbial action are described. Factors responsible for pathways of sucrose destruction are discussed. Problems other than sucrose loss, such as colorant formation and microbial polysaccharide development, are investigated. The quantities of sucrose lost under various conditions in process, and methods for the estimation of sucrose loss are discussed. An overall picture of sucrose loss, the reasons and results, from field to factory and refinery is presented.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI January 1981-No. 51
Energy Balance in Production of Alcohol in Sugar Refineries
The overall energy balance for production of alcohol from several crop systems is evaluated and compared. Sugarcane is one of the better sources on an energy balance basis.
In the production of alcohol in a sugar refinery, a system utilizing the waste streams such as molasses and sweet waters plus a small amount such as 5 or 10% of otherwise product sugar, would have the best energy balance.
Technical Report Nr. Cane Sugar Refining Research Project, Inc.\SPRI February 1981-No. 52
Color in Refinery Products
This report describes a study of the color balance in three refineries in the boiling through the 4th strike; the isolation and identification of several color precursors and decomposition products of sugar which occurred during refining; the results of our study of the particle size, molecular weight range and composition of the suspended material in solutions of refined sugar, and its effect on color measurements.
Technical Report Nr. SPRI 1981-No. 1
A Quantitative Method For Dextran Analysis
A method for the quantitative determination of dextran in sugar solutions is described in this report. The method is relatively rapid, (approximately 1 hour), and has no interference from starch or indigenous sugarcane polysaccharide (ISP), protein or salts. An important aspect of this new method in that it is independent of the molecular weight of the dextran used as a standard.
Technical Report Nr. SPRI 1981-No. 2
Flavor Components in Sugar Products
Compounds that contribute to odor and flavor in sugar products were identified by combined gas chromatography-mass spectroscopy and thin layer chromatography. The volatiles in cane leaves, raw sugar, molasses, and brown sugar were examined. Dimethylsulfide was found to be the major volatile in molasses, and acetic acid was the major volatile in brown sugar. Flavor thresholds and sources of these constituents are discussed
Technical Report Nr. SPRI 1982-No. 3
Phenolics in Sugar Products: Their Role in Flavor and Color Production
The role played by phenolic compounds in color formation and other aspects of sugar processing is reviewed. Little, however, is known about their role in flavor production. Seven adsorbents were evaluated for their ability to extract these compounds. XAD-2 was best suited for collecting a flavorful, phenolic-rich fraction from brown sugar which was evaluated by GC/MS.
Technical Report Nr. SPRI 1982-No. 4
Dextrans, Dextran Hydrolysis Products and Viscosity in Sugar Solutions
A problem of long standing is the effect of dextrans on the cane sugar refining process. One undesirable effect is that dextran increases the viscosity of sugar solutions, creating problems with yields and recoveries. This viscosity effect has been reexamined, and viscosity measurements have been made in a cane sugar system in which dextrans of different molecular weights have been hydrolyzed by a dextranase enzyme.
The effects of the products of dextranase action on sucrose crystal shape will be presented.
Technical Report Nr. SPRI 1983-No. 5
High Performance Liquid Chromatography (HPLC) in Sugar Factories and Refineries
High Performance Liquid Chromatography (HPLC) is well established as an analytical control in many industries, and has been in use in sugar industry research laboratories for some years.
In an assessment of the use of HPLC in plant operations, an H.P.L.C. dedicated to sugars analysis was taken into mill and refinery laboratories, and samples of juices, syrups, process liquors, molasses, waste waters and waters were analyzed.
With regard to factory operations, HPLC for juice analysis, false pol discovery and routine control will be discussed. In the refinery operations, HPLC as a technique for analysis of low grade syrups and liquors, water monitoring, dextran contamination, invert destruction, and fermentation, will be considered. HPLC is particularly useful for investigation of losses, and for problem solving and maintenance checks in factories and refineries.
Technical Report Nr. SPRI 1983-6
Mixing Bone Char with Granular Carbon
Consideration is given to the theoretical aspects of mixing bone char with granular activated carbon. The two adsorbents remove different colorants and so, collectively, do a more complete job and exhibit higher capacity than can be shown individually.
In ash removal, the negative effect of granular carbon is compensated easily by the bone char’s ion exchange function. IN regeneration, the different optimum conditions can be compromised. The differences in handling do not present the difficulties previously imagined.
Technical Report Nr. SPRI 1983-No. 7
The Sugar Refining Industry Today
This article was written at the request of Sugar y Azucar (Ruspam Communications, Inc., Sugar Journal) for their 1983 Yearbook.
Technical Report Nr. SPRI 1983-No. 8
Interference of Plant Polysaccharides and Tannin in the Coomassie Blue G250 Test for Protein
Coomassie Blue G-250, a quantitative color reagent used for protein analysis, reacts with tannin and polysaccharides found in cane juice and raw cane sugar. For this reason, the dye could not be used as a reagent for protein in these products. However, spectroscopic data showed that the complex formed with phenolic compounds possessed a different maximum than the protein complex. The spectrum of the complex between the dye and the nondialyzable fraction from raw sugar indicated the presence of phenolic moieties attached to this high-molecular weight fraction. The reaction of several common plant polysaccharides and tannins with the dye could constitute a serious source of error in its use to determine protein in plant extracts.
Technical Report Nr. SPRI 1983-No. 9
Acetic Acid, A Major Volatile Constituent of Brown Sugar: Origin and Measurement
Acetic acid was identified as the major volatile constituent of commercial brown sugars. These sugars contained levels ranging from 31 to 827 ppm. The source of the acetic acid was found to be bacterial action in recycled sweetwaters containing low levels of sucrose. Sugars manufactured without there waters had low to no detectable acetic acid levels. The method of analysis used—direct gas chromatography of sugars on the Dupuy inlet—provided a rapid, semi-quantitative result. A high level of variability in some of the sugars was attributed to uneven distribution of acetic acid in these sugars. Other volatile constituents due to bacterial action were methanol, ethanol, acetaldehyde and diacetyl.
Technical Report Nr. SPRI 1984-No. 10
Analytical Techniques for Sugars and Nonsugars
This material was written as Chapter 36, Analytical Techniques for Sugars and Non-Sugars, for the 11th edition of the Cane Sugar Handbook, updating material in Chapter 37 of the 10th edition. The information herein should be treated, with regard to referencing or quoting, as pre-publication copy. Some cross-references to other chapters are included.
Technical Report Nr. SPRI 1984-No. 11
Non-Sucrose Components of Cane Sugar and Efficiency of Press Filtration
This material was presented at the Sugar Industry Technologists’ Annual Meeting, on May 6-9, 1984, in Houston, Texas, USA. Proceedings S.I.T., Vol. 43, pp. 36-59
Technical Report Nr. SPRI 1984-No. 12
Seminar on Cane Sugar Technology in China, and Cane Sugar Industry
This Technical Report is part of the author’s report to the United Nations Industrial Development Organization on the visit. The author visited the People’s Republic of China, as a U.N.I.D.O. expert, on UNIDO funds, on annual leave from SPRI. These observations were the basis for recommendations to the Cane Sugar Research Institute, and the sugar industry in China. The recommendations are not included in this report.
Technical Report Nr. SPRI 1985-No. 13
Sensory Analysis of Brown Sugars and its Correlation with Chemical Measurements
A series of commercial brown sugars, including dark brown, light brown and turbinado sugars, produced by various methods, were subjected to flavor profiling by a trained sensory panel. A sensory profile and a flavor score for the sugars were developed for each sugar. Gas chromatographic analysis and chemical data for the sugars were regressed against the flavor scores. There were significant negative correlation of the flavor score with amino nitrogen, chloride, and ash, and positive, though insignificant correlation with fructose. The type of sugar, whether turbinado, light, or dark, affected the correlations.
Technical Report Nr. SPRI 1985-No. 14
Color Tests and Other Indicators of Raw Sugar Refining Characteristics
A series of tests for types of color, e.g. phenolic color, caramel color and melanoidin color, has been applied to several sets of raw sugars to develop a simple profile of color in each raw sugar. These color profiles are compared with the refining qualities of the sugars.
The contribution of each type of color to color measurements under various conditions of analysis is discussed.
Other factors influencing refining quality of raws, either alone or in combination with color bodies, including polysaccharides, are considered.
Technical Report Nr. SPRI 1985-No. 15
Current Application of HPLC in Sugar Analysis
Rapid analysis of the sugar content of cane juice, syrups, and other sweeteners can be accomplished using high performance liquid chromatography (HPLC) techniques. For example, carbohydrate analysis using an ion-exchange type column in calcium form, with refractive index detection, has been found to be a useful method for the analysis of cane juices obtained from bioregulator treated canes and deteriorated canes.
Methods for analysis of lactic acid and aconitic acid in cane juice and molasses have also been worked out in our laboratory using an HPX-87H organic acid ion-exchange column.
Current studies of the application of HPLC techniques in the analysis of difructose dianhydrides and disaccharides such as gentiobiose and isomaltose will be reported.
Technical Report Nr. SPRI 1985-No. 16
A Glucan From Sugarcane
The sugarcane plant contains several types of polysaccharide: starch, cell wall polysaccharides such as indigenous sugarcane polysaccharide, celluloses and hemicelluloses. Sugarcane products can also contain polysaccharides that are products of microbial metabolism, such as dextrans.
The isolation of a polysaccharide from fresh, unwounded sugarcane is reported here. The compound appears to be a glucan similar to phytoglycogen. Evidence for the structure presented is based on methylation analysis and enzymolysis.
Technical Report Nr. SPRI 1985-No. 17
Determination of Aspartame and its Breakdown Products in Soft Drinks by Reverse-Phase Chromatography using U.V. Detection
A rapid and simple analytical method is presented for the determination of aspartame and its breakdown products in carbonated soft drinks which had been stored at room temperature for various periods. The samples were analyzed by high performance liquid chromatography using a reverse phase column and U.V. detection at 215 nm, under isocratic conditions. Four breakdown products were identified and their relative proportions determined. No aspartame condensation product was observed. The data showed that aspartame is relatively unstable in these products from hydrolysis and cyclization account for the aspartame lost.
Technical Report Nr. SPRI 1985-No. 19
Color Components in Sugar Refinery Processes
Color in sugars is made up of several different chemical types of colorant. Simple tests have been devised to measure phenolic-type colorants, which are derived mainly from the cane plant, and amino-nitrogen colorants, which come from the cane plant and are made in process.
These tests are applied to raw sugars and process liquors from several refineries which employ a variety of processes. The effects of phosphatation and carbonatation on removal of the different color components are compared. Several decolorization systems are included in the study. The effects of bone char, granular carbon, mixed systems and ion exchange resins are reported.
The overall behavior of color components through refinery systems is discussed.
Technical Report Nr. SPRI 1985-No. 20
Instrument Error in Measuring Sugar Color
The error in measuring sugar color introduced by using different instruments was evaluated. Sources of error examined were: wavelength, bandwidth, detector response, cell placement, and scattered light. The largest source of error was due to failure to accurately achieve the required wavelength of 420nm, followed by variations in the handling of scattered light. Differences between instruments, even of the same make and model, of 5% to 8% are to be expected, and differences of 30% to 40% would not be surprising. In order to reduce the errors to a more acceptable level, tighter specifications on the instrument will be required. It appears that it may be necessary to use a mercury arc of laser for the light source. These instrumental errors account for only part of the observed error in the sugar color measurement. The error associated with sample preparation can be much larger.
Technical Report Nr. SPRI 2001-01
Membrane Treatment of Low Purity Recovery House Streams: Potential New Products Development Using Membranes
Membrane treatment of sugar processing streams holds great promise in reducing energy usage, reduction or elimination of chemical clarification and improved final product quality. Another promising area of application is in production of new products, such as organic sugar, or products from unusual sources in the process, such as the recovery house. The recovery house is an important area of the refinery, but one in which low purity samples are recycled back into the process to recover sugar, with the added expense of increased clarification demands and the introduction of additional impurities. A series of tests were undertaken using a Koch spiral membrane system to treat the various streams of the recovery house of a local refinery. Removal of total polysaccharides, starch, dextran, turbidity and color were noted, averaging 4 to 38% color removal, 93% turbidity removal, 73% starch removal, 63% dextran removal, and 73% total polysaccharide removal. The permeates from soft syrup (color>12,000 ICU) and affination syrup (color>20,000) were further processed into crystalline products. These “soft light” sugars, color<1000 had very pleasant aromas and appearance. The sensory characteristics of these new products are described.
Technical Report Nr. SPRI 2001-02
The Effects of Sulfur Dioxide in Sugar Processing Comparing Model Sucrose and Cane Juice Systems
Sulphur dioxide (SO2) has been used for centuries to minimize color in food processing and fruit and vegetable storage. In the sugar industry, it is used routinely by sugar beet processors to reduce and prevent color formation in white refined sugar. Sugarcane processors throughout the world use SO2 to produce plantation white sugars. This study was undertaken to determine the effect of SO2 on pure sucrose solutions in comparison to real factory sugarcane juice streams. Sugar systems included 15 brix pure sucrose, clarified juice and mixed juice from a Louisiana sugarcane mill. Milk of lime was added to pH 8.0 and the pH then lowered to approximately pH 5.0 with either SO2 or HCL as the control. Samples, ranging from pH 5 to 8, were held at 85C for up to 120 min. Treated samples were analyzed for pH, residual SO2, color, calcium, and invert (used as a measure of sucrose loss).
Results indicated that the model system was much more sensitive to small levels of SO2 than real juice samples. The pH levels dropped rapidly and invert levels increased with time. There was 1.6% loss of sucrose in the SO2 trial as compared with no sucrose loss with HCL.
Clarified juice resisted changes in pH with both SO2 and HCL. Sucrose loss at 120 min of processing at pH 5.0 was minimal (0.88%) with either SO2 or HCL. There was a maximum color reduction of 10-20% in the SO2, whereas a color increase of about 7% occurred in the HCL treatment. No sucrose loss was observed with HCL.
The mixed juice was very resistant to pH changes, and a minimum pH of 5.0 was achieved with 4800 ppm SO2. No sucrose loss was observed in mixed raw juice with either SO2 or HCL even after 120 minutes. Color reduction was higher with HCL than SO2, except for the highest level of SO2, where both effected about 30% color decrease.
Technical Report Nr. SPRI 2001-03
Composition of the Soluble, Nondialyzable Material in Raw Cane Sugar
The high molecular weight (HMW) material in cane sugar processing is of interest to processors because it is difficult to remove and has a tendency to be preferentially occluded in the sugar crystal, creating the potential for increased color and turbidity. The current work reports on the quantity and composition of HMW material in raw cane sugar.
The high molecular weight (HMW) material (>12,000 Da) of ten raw cane sugars from seven countries and two U.S. states was isolated by dialysis and analyzed by gel permeation chromatography (GPC). Simultaneous detection of colorant polymers and polysaccharides was accomplished by using two detectors in series: UV at 214 nm for colorant polymers and refractive index (RI) for carbohydrate polymers. The monosaccharide composition of the nondialyzable raw sugar fraction (the tenate) was determined by gas chromatography following hydrolysis. Aconitic acid was associated with the tenate. The raw sugars could be categorized into two types according to their GPC patterns and the aconitic acid content. Hydrolysis of individually collected GPC peaks demonstrated that one particular peak contained most of the aconitic acid.
Technical Report No. SPRI 2002-04
Commentary on HACCP in Raw Sugar Processing: Assuring Consumer Safety and Regulatory Compliance: A Look to the Future
Hazard Analysis by Critical Control Point (HACCP) is a management tool used to ensure food safety. It is a proactive determination of potential health risks that focuses on prevention rather than after-the -fact remediation. It is an effective alternative to conventional end-point testing and response to problems after they have occurred. In the United States, HACCP systems are expected to reach the entire food spectrum within the next few years. With companies considering the production of food grade sugar at raw sugar mills, the expectation is that the principals of HACCP, along with GMPs (Good Manufacturing Practices) will be implemented in raw sugar mills. This commentary briefly reviews the principles and procedures of HACCP, some potential hazards in raw sugar manufacture and aspects of implementing a HACCP program in a sugar mill.
Technical Report Nr. SPRI 2002-05
Turbidity Measurement of Sugar: Comparing NTU and ICU Methods
Turbidity is an important quality factor for white granulated sugar in many applications, especially for beverage manufacture. Most official sugar standards, such as Food Chemicals Codex (FCC), National Formulary (NF), and Codex Alimentarius, do not have a specification for turbidity. This is probably because turbidity is basically a quality parameter that is not likely to impact the health and nutritional status of sucrose. Nevertheless, sugar customers are interested in specifying reasonable turbidity standards for the products they buy. Two methods are available for turbidity measurement – nephelometry and a difference method using the ICUMSA color procedure (difference in ICU before and after filtering). Since both methods are in common use, this study was undertaken to determine if there was a correlation between the two methods. The results showed a strong correlation. Expected turbidity ranges for various types of sugars, in both ICU and NTU values, are shown.
Technical Report Nr. SPRI 2002-06
The Specialty Sucrose Market: A Look at an Important Niche
The sugar industry basically has three areas for economic expansion: (1) Incremental improvements in processing that increase yield, energy efficiency, or other desirable processing parameter; (2) cogeneration and by-products, and (3) new uses of sucrose as a specialty food product or new types of specialty sugar. The first two avenues, incremental process improvements and by-products, have been covered elsewhere. The value-added specialty sucrose niche, on the other hand, has received less coverage. In recent years, “unrefined,” “less refined,” “natural” and organic products have developed a strong following and are growing at a rapid pace. Part of this is due to the appealing descriptions used in marketing campaigns, but a lot of the appeal also taps into the desire of many consumers to use less processed foods in their diet or to eat food products that are perceived as more environmentally friendly. This report reviews some of the sugar products on the market, the pitfalls and promise of specialty products, and some speculations as to what the future may hold.
Technical Report Nr. SPRI 2002-07
Effect of Macromolecules on Sugar Processing: Comparison of Cane and Beet Macromolecules
The major macromolecules in sugar processing include colorant and polysaccharides, along with minor amounts of protein, soluble lignin, colloidal silicates and possibly calcium complexes. These high molecular weight components negatively affect sugar processing and have been implicated in the inclusion of color in crystals, formation of color on storage, processing problems, and final product quality issues, such as turbidity and acid beverage floc. It has long been accepted that the high molecular weight components are the most difficult to remove during refining. However, it is also of interest to note that the transfer of color (from syrup to crystal) is much higher in cane sugar processing than in beet sugar processing. White beet sugar, with color of 20-30 IC, can be boiled from 2000-3000 IC color syrup, but only from about 200 IC cane syrup. In chromatographically separated beet molasses extract, the color of the syrup can be as high as 5000-7000 IC and still produce a 30-50 IC sugar. What is the reason for this? This report presents recent studies that compare beet sugar and cane sugar colorant and polysaccharide. The results indicate that beet and cane colorant are fundamentally different: Beet colorant tends to be produced during processing, mainly from alkaline degradation of invert and melanoidin formation, while cane colorant enters the process in the cane juice as plant pigments associated with polysaccharide, and changes very little in process, due to the milder conditions associated with cane processing.
Technical Report Nr. SPRI 2002-08
A Rapid Starch Test For Use in Cane Mills
A project entitled, “Rapid Screening Analysis for Starch in Cane Juice,” was approved for additional funding to Sugar Processing Research Institute, New Orleans, Louisiana, from the American Sugar Cane League, for the 2001-2002 season. A simple, rapid, quantitative test for starch was developed and validated. The method is shown in Appendix 2 of this report. During the 2001/2002 season, SPRI personnel visited a Louisiana cane mill to use the rapid screening test on site with real-time samples. Samples were also taken back to the SPRI labs to determine the starch content by the standard starch method for comparison with the rapid test results. Results showed good correlation (>95%) between the calibration curves for the standard method and the rapid method. The method can be used on raw juice, clarified juice and raw sugar. It is recommended to use the test on clarified juice, since the starch in clarified juice will reflect the starch content going forward in process. This can help factory personnel decide if amylase dosing is necessary. Currently, amylase enzyme is dosed continuously in most Louisiana mills. The method is simple and rapid, can be easily learned, does not use any new equipment not already on hand in most mill laboratories, and can be integrated into current laboratory practices. This study also showed the behavior of starch in the mill during the season.
The mean starch in raw mixed juice over the period studied was 1054 ppm, and in clarified juice, it was 844 ppm. This would indicate approximately 16% reduction in starch by clarification. Given the high levels of starch in the raw juice, this is not a significant decrease, and would indicate a need to continuously dose amylase enzyme.
Technical Report Nr. SPRI 2003-09
Comparison of Two Methods of Volatile Analysis for Determining the Causes of Off-Odors in White Beet Sugars – – SPME and Headspace.
White beet sugars periodically have off-odors, causing them to be rejected by customers. An understanding of the nature and source of the compounds responsible will help in eventually eradicating the problems that cause them. However, determining volatile substances in white sugar is challenging because the amounts present are very small, often in the parts-per-million or even parts-per-billion range. In this study, we describe a set of white beet sugar samples that were received from several locations. Each sugar was given an over-all sensory rating of: 1 = acceptable; 2 = borderline; or 3 = reject, by a sensory panel. The samples were analyzed by two methods of volatile analysis. The two methods investigated were Solid-Phase Micro Extraction (SPME) and headspace analysis. Sample chromatograms were evaluated for compounds at mass to charge ratio (m/z) 60, where volatile fatty acids are found, with the exception of propionic acid. Representative chromatograms illustrating acceptable, borderline, and reject sugars are shown. It was found that samples in the acceptable and borderline categories appeared to have lower levels of the more volatile fatty acids than did the reject sugars. This was true for both SPME and Headspace. However, it was apparent that SPME was a better technique for volatile analysis.
Technical Report Nr. SPRI 2003-10
The Effect of Ozone on Off-Odors in Beet Sugar
This study investigates ozone as a potential new polishing agent for the elimination of off-odors periodically present in beet sugars.
Ozone was directly applied to crystalline sugars to oxidize volatile compounds responsible for off-odors and various treatment times, temperatures and ozone concentrations were tested in order to determine the optimum conditions for best ozone action. Volatile off-odor compounds were extracted and analyzed using solid phase micro extraction-gas chromatography-mass spectrometry (SPMe-GC-MS). The effect of ozone on the volatile fatty acids (VFA) profile was closely monitored, since VFA have been established by SPRI and other researchers as the most significant source of off-odors and off-flavors in beet sugar.
Results showed that, depending on concentration, temperature and duration, ozone treatment could induce development of new compounds, increase some existing compounds or remove most of the volatiles from the treated sugar, eliminating all traces of off-odors (measured subjectively by sniff testing).
Technical Report Nr. SPRI 2006-11
STOC – Sucrose Thermal Oligosaccharide Caramel – A Potential New Use for Sucrose
There is ongoing interest in creating new and useful products from sugar and sugar processing by-products. An interesting category of potentially valuable products are those known as Sucrose Thermal Oligosaccharide Caramel (STOC), which can be used in animal feel, especially for poultry and pigs. In poultry, STOC has been shown to enhance the growth of chickens and to decrease odor production in the manure of pigs. It may also potentially reduce the amount of antibiotic required in animal feed.
In 1993 researchers at the University of Montana developed a sucrose thermal oligosaccharide caramel product (STOC) using controlled pyrolysis of sucrose (Manley-Harris and Richards, 1993). Amorphous sucrose, heated with citric acid, was found to produce fructoglucan in 30% yield. It functions as a feeding supplement for enhancing the growth of broiler chickens (Orban, et al., 1997) and may have applications as a low calorie bulking agent or fat substitute in food.
The process is simple, involving only two ingredients, sucrose and citric acid, which are both readily available and cheap. The basic technology includes grinding, cooking and cooling, which can be made continuous, and lends itself to large scale production. If the product can indeed stimulate the growth of poultry and possibly other animals and replace some antibiotics, it should be a rather high value product, probably about ten times the cost of production.
Technical Report Nr. SPRI 2006-12
The Potential for Sucrose Esters In Detergent Compositions
There is ongoing interest in creating new and useful products from sugar and sugar processing by-products. An interesting category of potentially valuable products are sucrose esters. Although sucrose esters have been known for a long time and have many commercial uses, current interest in finding new products with a more environmentally friendly profile has led to increased interest in formulating detergents with sucrose esters.
In considering the use of sucrose esters in detergents, some important questions need to be addressed:
1. Who already produces sucrose esters?
2. How to penetrate the market?
3. What are the competing products and/or barriers to the use of sucrose esters?
4. Who will be the customers?
5. How much will it cost? Will it be profitable?
6. Should we produce the ester ingredients only, or get into the detergent and cosmetics business?
This report will give a brief overview of sucrose esters in detergents and their potential as detergent components.
Sucrose esters fall into the category of non-ionic surfactants. Today, use of non-ionic compounds is increasing because ionic surfactants (cationic or anionic) can form complexes with various ions (iron, calcium) that can adversely affect performance. Non-ionic surfactants are especially valuable in food production. Sucrose esters have been shown to make excellent detergent materials. There is no doubt that there is an expanding market for sucrose esters in the areas of food, cosmetics and detergents. One must always keep in mind that China appears to be growing this segment.
Firms are looking for ways to enhance their premium products and looking to adapt their cleaning chemistries to less expensive products that can be sold in the developing world. The laundry detergent business is slow growing, but it is still a lucrative ingredient market. Many textile care successes are from developing markets. However, consumers in developing countries often can’t afford brands that contain premium ingredients. Consequently, detergent markers are working to modify their formulas for sale in the developing world.
Proctor & Gamble, for example, developed P&G’s Tide Clean White, a Chinese brand that went through a unique development regime. The process started with market research, which revealed that some of the ingredients used in conventional P&G products were not adding value in China, only expenses. The company found out that the Chinese consumer wants basic cleaning. As a result, P&G removed unnecessary ingredients and rebalanced the remaining ingredients and added ingredients the Chinese valued, including more brightener and a perfume system designed for Chinese preferences. (C&EN, 2005)
Technical Report Nr. SPRI 2006-13
Reduction of Lime Usage with Cationic Aluminum Coagulants in Juice Clarification
Abstract – Report to the American Sugar Cane League
This report is in reference to a Research Proposal made to the American Sugar Cane League by Sugar Processing Research in January 2005, which was funded for research during the 2005/2006 grinding season.
SPRI work on the potential of cationic aluminum coagulants in cane juice clarification has been ongoing since 2004, and is part of a larger research effort by SPRI to examine ways to improve clarification. Earlier studies had looked at the effects of using dolomitic limestone and magnesium compounds as well as admixtures with soda ash in clarification. Preliminary experiments treating raw cane juice with polyaluminum coagulants (PAC) on a bench scale in the laboratories of Sugar Processing Research Institute have shown a great deal of promise in the removal of Color, Turbidity and Polysaccharides. During the course of the bench scale investigations in 2004, we noted that aluminum alone significantly removed turbidity, color and polysaccharides from the juice, leading to a proposal to investigate polyaluminum coagulants (PAC) as a means to decrease lime usage in the mill.
Aluminum-based compounds are used to purify water to remove color and sediment in waste water from other industries. Aluminum compounds are used to remove organics, phosphate, color, iron and suspended particles from water. Aluminum sulfate and polyaluminum chloride (PAC) are the primary chemicals used to treat drinking water. Aluminum sulfate is used in the yeast industry to remove phosphate and color from molasses waste water after fermentation, to make it acceptable for discharge into waterways. Aluminum oxides are scavengers of phosphate and silicate. There are reports of the ability of aluminum to remove arsenic and fluoride from groundwater. Aluminumchlorohydrate is used around the world as an alternative to lead clarification in polarization of sugar solutions.
Use of aluminum is sugar processing is not widespread. A report on the potential of aluminum compounds for raw sugar decolorizing was published in 1999. A 1999 patent described the use of PAC to decolorize sugars solutions, sugar alcohols and betaine. It was recently reported that PAC has been used in Brazil at the level of 400-800 ppm to produce direct consumption white sugar to avoid sulfitation and also in India for the same purpose at the level of 1000 ppm.
Technical Report Nr. SPRI 2006-14
Isolation of Proanthocyanidins and Other Antioxidants from Cane Juice
Abstract – Report to the American Sugar Cane League
Interest in phenolics in food has increased greatly because of their antioxidant and free radical scavenging abilities, which contribute a number of health benefits in the diet, including anti-cancer and cholesterol-lowing functions. The food supplement industry has taken note of research showing the content of beneficial phenolic compounds in various agricultural products and sells extracts containing these. Among the most sought after ingredients are those with antioxidant properties, in particular, the proanthocyanidins and condensed tannins.
The cane plant contains several polyphenolic compounds which have been identified as antioxidants. Proanthocyanidins, also known as condensed tannins, are a class of compounds with a high antioxidant value. These compounds are identified by their conversion to red pigments (anthocyanidins) when treated with heat and acid. Work at Sugar Processing Research showed that sugarcane juice from several varieties contain significant quantities of these types of compounds. SPRI developed a simple method for extracting a deep red anthocyanidin pigment from variety CP72-370 cane juice.
In this study, we measured the antioxidant strength of cane juice from nine cane varieties using the RandOx Total Antioxidant Status test kit. We also measured the production of anthocyanidins in the juice of nine cane varieties. The anthocyanidins are developed when the cane juice pH is adjusted to 3.2 – 3.5 and heated briefly to about 70-80ºC, causing hydrolysis of the condensed tannins.
Technical Report Nr. SPRI 2007-15
Laboratory Studies on the Effect of Enzymes on Color, Turbidity and Total Polysaccharides in Sugar beet and Sugarcane Juice
Control of color, turbidity and polysaccharides is important in sugar beet and sugarcane processing. Controlling these parameters as early as possible in the process will provide benefits to the manufacturer in terms of lowered use of processing aids, improved filtration, better sugar recovery, and higher quality products. Twenty-eight commercial enzymes with targeted functionalities were examined for their ability to reduce color, turbidity and/or polysaccharides in raw beet and raw cane juice. Juices were treated with 500 ppm enzyme for 30 min at 50° C and monitored for reduction of color, turbidity and total polysaccharide content. For beet juice, enzymes with hemicellulase, pectinase, xylanase, and glucanase activity removed significant color or polysaccharide. For cane juice, enzymes with hemicellulase, cellulase, xylanase, and glucosidase activity were the most effective. Several enzymes also decreased turbidity.
Technical Report Nr. SPRI 2010-16
Floc Prediction in Refined White Cane Sugar: The SPRI Rapid Floc Test
As a result of research conducted by SPRI, a rapid test to predict floc formation in refined white cane sugar has been developed. The test is based on the association SPRI has discovered between an absorbance ratio (AR) and floc potential. Numerous refined white cane sugars have been tested in our laboratory and a strong correlation exists between the AR ratio and the currently used 10-day floc prediction test. A white sugar solution is prepared and filtered to remove turbidity. The absorbance is measured at two different pH levels. The ratio of the absorbances is known as the Absorbance Ratio (AR). SPRI has studied many quality parameters of white sugar such as pH, color, turbidity, and total polysaccharide but AR seems to be the quality parameter which correlates best to the floccing potential of the sugar.
Technical Report Nr. SPRI 2011-17
Study of color formation of white beet sugar produced during thick juice campaign
SPRI has long had an interest in studying the changes in color during storage of various sugar products. Observations at sugar beet factories have noted that sugars produced from stored thick juice tend to increase in color during storage in silos at a higher rate than sugars produced during the beet campaign. This study showed a strong correlation between color and storage time for thick juice as well as molasses extract. While completing this study the color in thick juice over time, changes in several organic acids over time were found. This study consists of samples initial quality analysis, Ethanol washing, Accelerated storage, Laboratory storage, and results in the investigation of organic acids analysis.
Technical Report Nr. SPRI 2012-18
Processing of Sugarcane & Sugar beet: Characterization and Improvement of Sugarcane and Sugar beet Process Units
SPRI conducts research within the international sugarcane and sugar beet industries to solve processing problems common to various segments of the industry. The major underlying issue in sugar processing research is to understand the factors that contribute economic viability within the industry including yield and quality of lack of quality in final products. Final products include raw sugar, white cane and beet sugar, brown sugar, edible syrups or liquid sugar, and direct consumption white sugars, including sugars used around the world to produce various beverage products. Both yield and quality (including sensory issues) are impacted by the presence of minor components. Important minor components include invert sugar, polysaccharides, organic acids, inorganic ash components and volatile compounds, which may arise from the cane or beet plant, the manufacturing process, from plant diseases, or from other factors.
SPRI is exploring innovative treatments within the manufacturing process to remove and/or prevent or ameliorate the deleterious effects of some of these constituents, such as by the use of membranes, hydrogen peroxide, ozone, enzymes, other compounds, or mechanical means to produce higher quality as well as new, high-value products form low purity sugar streams in the factory. This report documents research conducted under a Specific Cooperative Agreement between ARS and SPRI.
Technical Report Nr. SPRI 2013-19
Canty Inflow Particle Sizing System
In an effort to gain a better understanding of what occurs during clarification with regard to turbidity and particle size, SPRI has been using the Canty portable InFlow particle sizing system. Canty Particle Sizing Analyzers have been engineered to analyze liquid samples under varying pressures, temperatures and flow rates. It offers sample or continuous, microscopic, non-destructive viewing and provides particle size analysis with two dimensional results when used in conjunction with the CantyVisionClient™ Software. The vision system, with integral lighting, features precision optics designed to enhance the image prior to display or analysis. The image sensor is a high resolution/high speed CCD camera coupled to a microscopic lens system. The system offers zoom and focus ability, variable lighting, and multiple objective lens packages to cover a range of sizes. The Canty Particle Sizing Systems features the FUSEVIEW™ window as the product contact barrier. SPRI has looked at sugar beet and sugarcane processing products as well as sorghum juices using this system.
Technical Report Nr. SPRI 2014-20
Microbiological issues in white sugar
Refined white sugar, in general, does not support microbiological growth by virtue of its low water activity. Conditions of production and refining, which include high temperatures and high sugar concentrations also help mitigate the growth of most microorganisms. Nevertheless, there are some organisms of concern that could be present, and both the white sugar producer and the customer have a strong interest to assure the safety and hygiene of sugar and to prevent spoilage or contamination of the final food product it is used in. Other sugar products, such as soft (brown) sugar, liquid sugars and syrups have a greater possibility for supporting microbial growth by virtue of their higher moisture content.
This report presents a brief review of microbiological issues in white sugar. Topics covered include: Sources for microbes to enter the system, organisms of concern, challenge studies and the microbiology of white/refined sugar, methods of control, specifications, soft sugars, liquid sugars and syrups and test methods.