RI-ERP-FINALACTION-Recommendations

× 1/ W

E × 162/180 × 100] – free glucose %

where subscript F represents values for samples analyzed for free glucose and subscript E represents values for samples treated with amylase and amyloglucosidase; A CF , A CE = absorbance of reaction solutions minus the absorbance of the appropriately diluted reagent blank, values are averages of the two replicates for each test solution; Q = quadratic slope term, S = linear slope term, and I = intercept of the standard curve to convert absorbance values to µg glucose/mL; V F , V E = final sample solution volume, ca 50.0 mL for V F and 51.1 mL for V E if done by summation of volumetric additions, otherwise, by size of volumetric flask used; DF = dilution factor, e.g., 0.5 mL sample solution diluted into 5.0 mL = 5.0/0.5 = 10; 1 g/1 000 000 µg = conversion from µg to g; W E , W F = test portion weight, as received; 162/180 = factor to convert from measured glucose as determined, to anhydroglucose, as occurs in starch. If test samples are run in duplicate portions, the free glucose % in the dietary starch equation is the average free glucose % value determined for the test sample. References: (1) Food Chemicals Codex (2014) 9th Ed., The

United States Pharmacopeial Convention, Rockville, MD, USA, Appendix V, Enzyme Assays, α-Amylase Activity (Bacterial), pp 1392–1393

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