Sugars color development

Spectrophotometric and chromatographic studies indicated that the color-bearing compounds responsible for the sugar color development were 5-HMF, caramel, humic acids, and melanoidins. Reduction of these compounds by improving first carbonation technique to minimize reducing sugar destruction would improve color development of the carbonation sugar. 

An important consequence of sucrose degradation is the development of color from degradation products. Kuridis and Mauch60 have developed an equation for the prediction of color development in model sucrose solutions. Color development was expressed as a function of temperature (90 to 120°C), time (0 to 80 min), pH (7.5 to 9.5), and composition of the solution (sucrose 20 to 60%, invert sugar 0.02 to 0.18%, and amino acids 1 to 3 g/L). The authors claimed, with caution, that the effects of an intended alteration in a unit process in the refinery can be predicted in advance. 

Secondary amines may also interact with reducing sugars. However, the reaction cascade does not proceed beyond the formation of the imine, and thus no coloration develops (22). 

Iron. Excess iron in wines causes cloudiness, interferes with the color, and can impair flavor. The mechanism of ferric phosphate precipitation has been intensively studied, and numerous colorimetric methods have been developed. For routine purposes the color developed with thiocyanate is adequate (6,9), but many enologists prefer the orthophenanthro-line procedures (3, 4, 6, 22). Meredith et al. (Ill) obtained essentially the same results for iron using 2,4,6-tripyridyl-s-triazine (TPTZ) to develop the color. Atomic absorption spectrophotometry can be used but, as with copper, corrections for reducing sugar and ethanol are necessary (51). 

These tubes will be used for termination of the reaction and for color development of the reducing sugar. 

Studies on the Color Development in Stored Plantation White Sugars... 

Xylanase was assayed using birchwood xylan as substrate. The solution of xylan and the enzyme at appropriated dilution were incubated at 75°C for 3 min, and the reducing sugar was determined by the dinitrosali-cylic acid procedure (12) with xylose as standard. The released color development was measured spectrophotometrically at 540 nm. One unit of enzyme activity was defined as 1 pmol of reducing sugar released 1 min under the described assay conditions. Protein concentration was measured by the Lowry method (13) using bovine serum albumin as standard. 

Several reactions can cause color development in starch-derived sweeteners. Because they contain reducing sugars, they will react with proteins and amino acids... 

Full color development can be achieved with a fewer number of application stages. This results in significant time savings, yet produces a final product that has all the properties of the standard sugar-coated tablet plus increased light stability. Raw material costs are also improved. 

Lactose is a disaccharide comprised of glucose and galactose units. These reducing sugars are reported to be present in spray dried lactose, as is the hexose degradent 5-hydroxymethyl furfural.This aldehyde has the potential for additional reactions with primary amino groups, Schiff Base formation and color development (Fig. 

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