Spelt wheat tempe as a value-added whole-grain food product

Abstract

Spelt wheat (Triticum aestivum) is an eco-friendly low-input crop whose consumption is considered advantageous. In this paper, a procedure for obtaining tempe-type products from whole grains of spelt and green spelt (immature grains) is presented, and the effect of biotreatment on the bioactive and nutritional parameters is described. The soluble antioxidant potential of the cooked grains (antiradical activity, reducing power, the sum of compounds reducing Folin's reagent) was enhanced after fermentation with Rhizopus oligosporus ATCC 64063, on average by 100% (buffer extracts) and 70% (acetone/water 1:1 v/v extracts). Spelt tempe also contained 25% more soluble phenolic acids, including a 300% higher ferulic acid level. As compared to cooked spelt, tempe contained more protein (12.7 g/100 g dry matter, dm) and ash (1.9 g/100 g dm), similar contents of total dietary fibre (11.3 g/100 g dm) and fat (2.7 g/100 g dm) but less starch (63 g/100 g dm). The nutritional parameters of spelt and green spelt were significantly improved by the fermentation. Tempe contained partially hydrolysed protein and total dietary fibre enriched in its soluble fraction (by 40% in green spelt tempe). Spelt grains, especially green spelt, can be considered a valuable substrate for obtaining a convenient value-added fermented food product.