Effect of the types and concentrations of alkali on the color of cocoa liquor

摘要

BACKGROUND: The alkalization process is extensively used in the cocoa industry, but information is scarce and not easy to acquire. The goal of the study was to evaluate the effect of different types and concentrations of alkali on the color of cocoa liquor. Dried beans from Chuao (state Aragua, Venezuela) were used to produce cocoa liquors. Samples of liquors were alkalized with solutions of NaHCO3, Na2CO3 and NaOH at concentrations of 10, 20 and 30 g kg(-1).RESULTS: The data showed that values of the coordinates L*, a* and b* decrease when liquors were treated with the three different types and concentrations of alkalis. Almost all samples had Delta E* values above 1. The ratios b*/a* and a*/b* and the proximate composition were also modified. Crude protein, crude fat and polyphenol concentrations were decreased and the ash content augmented as concentrations of the alkalis were increased. The fatty acid and sugar profiles were also affected. These ratios were most pronounced when NaOH was used.CONCLUSION: The selection of the type or concentration of alkali is a function of the type of product to be elaborated. (C) 2009 Society of Chemical Industry