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Drag these components to the right places in the scheme.

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The final part of the case will focus on the determination of fibre and non starch polysaccharides. In the end, fibre and NSP analysis will be added to this scheme.

Based on the information you studied on sugar and starch analysis you can complete the scheme below. This scheme gives a more detailed overview of direct available carbohydrate analysis compared to the scheme given at the start of this chapter. This new scheme shows in detail how the analysis of individual sugars and starch fit into the whole picture of available carbohydrate analysis.

Not completely right. Before the sugars are extracted from the food sample, first the food sample need to be defatted. This is important if the sample is high in fat because fats can interfere with sugar analysis. After extraction of the fat, the defatted and dried sample is used for further analysis.

Not completely right. Sugars are soluble in 70-80 v/v ethanol. Therefore, after extraction with 70-80 v/v% ethanol, the extract contains free sugars, oligosaccharides. However, also organic acids and sugar alcohols are soluble in 70-80 v/v % ethanol. After this extraction procedure the residue contains polysaccharides (and proteins, lignin etc) because these components are not soluble in 70-80 v/v% ethanol.

Not completely right. After extraction with 70-80 v/v% ethanol the carbohydrates in the extract are analyzed. Depending on the methods that are used for these analysis, this resulted in values for individual free sugars, i.e. mono-, di-, and oligosaccharides or in a single total values for free sugars expressed in monosaccharide equivalents.

Not completely right. After extraction of free sugars the remaining residue contains various polysaccharides. Among these polysaccharides are starch. This starch is hydrolysed and precipitated in 80 v/v% ethanol. The resulting glucose is measured and converted to starch values (using a hydration factor of 0.9). After hydrolysis of starch the residue still contains all non starch polysaccharides/fibre.

Right. Now the scheme gives an overview of the analysis of available carbohydrate analysis by direct measurement of individual sugars and starch. Hereby you finished the part on carbohydrate analysis. The next part of the case focuses on the analysis of fibre.