Influence of germination of quinoa (Chenopodium quinoa) and amaranth (Amaranthus) grains on nutritional and techno-functional properties of their flours

JIMENEZ M.D.; LOBO M.; SAMMÁN N.

JOURNAL OF FOOD COMPOSITION AND ANALYSIS

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2019 vol. 84 p. 1 - 8

0889-1575

The germination process produces changes in grains that mayaffect the nutritional properties and technological characteristics oftheir flours. The aim of this work was to determine nutritional changesin quinoa (Chenopodium quinoa) and amaranth (Amaranthus) flours, inducedby germination under controlled conditions. Proximal composition, proteindigestibility, starch and fibers were determined by AOAC methods. Totaland reducing sugars (Dinitrosalicylic acid method) and protein fractions(SDS-PAGE) were determined in flours. Amylose content (spectrophotometricmethod) was determined in starch. Thermal behavior of flour was studiedby DSC. Protein content and digestibility, and reducing and total sugarswere increased by germination. Protein degradation was observed infractions with molecular weights higher than 24 kDa in quinoa, while inamaranths through the molecular weight range (14-66 kDa). Apparentamylose content increased, possibly due to dextrinization of amylopectin.Gelatinization temperatures were similar between samples before and aftergermination. In the sprouted grain, flours gelatinization enthalpies weresignificantly lower than in unsprouted, also a greater tendency toretrogradation was determined. Germination improved the nutritionalcontributions of quinoa and amaranth flours, but the starch contentdecreased and the gel became more unstable, important features if theywill be used as ingredient in food formulations.