Reducing Sugar Analysis

Phosphorus, fatty acids, carbohydrates, glycerol, and amino acids were analyzed by the method described in our previous paper [8] and references cited therein. SDS-PAGE [8], TLC [9], HPLC [9], determination of phos-phomonoester [8], reducing sugar analysis [13], methylation analysis [14], and hexose analysis [15] were performed as described in the respective literature. Two dimensional TLC was performed on silica-gel plate (Merck Silicagel 60 F254 No. 5715) using the solvent systems, chloroform-methanol-acetic acid (65/10/1, v/v/v) for the first development and chloroform-methanol-25% ammonia solution (65/10/1) for the second. 

In the sugar industry, where the goal is to determine the exact amount of sucrose present, the analysis of other components is essential to determine purity. The most important of these, besides reducing sugars discussed, are moisture, ash, and color. Also relevant are methods used to determine particle-size distribution and insoluble matter. 

Composition. Molasses composition depends on several factors, eg, locality, variety, sod, climate, and processing. Cane molasses is generally at pH 5.5—6.5 and contains 30—40 wt % sucrose and 15—20 wt % reducing sugars. Beet molasses is ca 7.5—8.6 pH, and contains ca 50—60 wt % sucrose, a trace of reducing sugars, and 0.5—2.0 wt % raffinose. Cane molasses contains less ash, less nitrogenous material, but considerably more vitamins than beet molasses. Composition of selected molasses products is Hsted in Table 7. Procedures for molasses analysis are avadable (59). 

Peris-Tortajada, M., Puchades, R., and Maquieira, A. (1992). Determination of reducing sugars by the neocuproine method using flow injection analysis. Food Chem. 43,65-69. 

Thus, a multibiomarker tracer analysis of both water-soluble and hydrophobic organic compounds in various environmental samples using the GC-MS analytical method is useful. The saccharides, i.e. monosaccharides, disaccharides, anhydrosaccharides, and polyols (reduced sugars) are an important class of water-soluble compounds to be considered as environmental tracers. 

Samples of the sugars being removed are cooled to 20°C. and tested for density by a sugar Brix spindle., Analysis of these solutions shows that the reducing sugar content of the solutions is 60 to 70% of the concentration shown by the Brix spindle. If the hydrolysis of hemicellulose is not complete, the ratio of reducing sugar to Brix will be low and will indicate that insufficient acid has been used. 

This oxidation has been used to determine the anomeric nature of sugar residues in oligosaccharides.153 The oligosaccharide is reduced to the alditol, this is acetylated, and the ester is treated with chromium trioxide in acetic acid in the presence of an internal standard. From the sugar analysis of the product, the residues that have survived (and, consequendy, are a-D-linked) may be identified. The... 

Copper. In the presence of sulfur dioxide, copper-protein cloudiness may develop in white wines. Only small amounts of copper (about 0.3 to 0.5 mg/liter) cause cloudiness. Widespread use of stainless steel in modern wineries has reduced copper pickup, but many wineries routinely test their wines for copper. Atomic absorption spectrophotometry is the method of choice (51) although reducing sugars and ethanol interfere, and correction tables must be used (107). To reduce this interference, chelating and extracting with ketone is recommended (108). Lacking this equipment colorimetric procedures can be used, especially with di-ethyldithiocarbamate (3, 4, 6, 9,10, 22,109). Neutron activation analysis has been used for determining copper in musts (110). 

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