Browsing by Subject "kaakaomassa"

The literature review of this master’s thesis dealt with the definition of dietary fiber, cocoa bean and content of its cell wall. Cocoa processing was also included in this literature review. The objective of the experimental part of this thesis was to determine the dietary fiber content and its monosaccharide composition from cocoa mass and 70 % dark chocolate. The geographical effect to dietary fiber content of cocoa and the effect of chocolate processing to dietary fiber content of chocolate was also studied. Dietary fiber was analyzed using enzymatic-gravimetric AOAC 991.43 method. Fructans and fructo-oligosaccharides were analyzed from soluble dietary fiber filtrate and from defatted samples using enzymatic-colorimetric AOAC 999.03 method. Raffinose-series oligosaccharides were analyzed using liquid chromatographic (HPAEC-PAD) method. Monosaccharide composition was determined from soluble and insoluble dietary fiber fractions using acid methanolysis. Acid methanolysis doesn’t hydrolyze crystalline cellulose. Total dietary fiber content in LA1-cocoa mass was 20,7 ± 0,3 %, in LA2-cocoa mass 20,5 ± 0,2 %, in A1-cocoa mass 17,3 ± 0,4 %, in A2-cocoa mass 17,5 ± 0,6 %, and in chocolate 11,8 ± 0,1 %. Fructo- and raffinose-series oligosaccharide concentrations in all samples were less than 1 %. Polysaccharide concentration which doesn’t include cellulose was in LA1-cocoa mass 6,3 ± 0,3 %, in LA2-cocoa mass 7,0 ± 0,4 %, in A1-cocoa mass 6,0 ± 0,5 %, in A2-cocoa mass 7,5 ± 0,5 %, and in chocolate 4,3 ± 0,3 %. All concentrations are reported on wet weight basis. Monosaccharide composition consisted of arabinose, galactose, glucose, xylose, mannose, rhamnose, galacturonic acid, and glucuronic acid, of which arabinose, galactose, and galacturonic acid were the most common. There was a geographical difference in total dietary fiber concentrations of cocoa masses. Chocolate processing was not found to affect dietary fiber content of chocolate as the dietary fiber content of 70% dark chocolate was about 60–70 % of the dietary fiber content of cocoa masses. Polysaccharide concentrations of the samples were only one third of their total dietary fiber concentrations. Based on monosaccharide composition and literature, it could be concluded that the cell walls of cocoa are mainly composed of pectin. The composition of dietary fiber fractions should be studied more as acid methanolysis can’t hydrolyze crystalline cellulose which forms, based on literature, 30 % of cocoa’s cell wall polysaccharides. However, acid methanolysis is suitable for acid carbohydrate and heteropolysaccharide analysis. Lignin and other insoluble polyphenols and Maillard reaction products of dietary fiber fractions were not analyzed in this study.