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This study characterized and compared 13 gluten-free (GF) flours (rice, brown rice, maize, oat, millet, teff, amaranth, buckwheat, quinoa, chickpea, gram, tiger nut, and plantain) for their nutritional and functional properties. For all GF flours investigated, starch was the major component, except for gram, chickpea, and tiger nut flours with lower starch content (<45%), but higher fiber content (8.8–35.4%). The higher amount of calcium, magnesium, zinc, potassium, phosphorus, similar values for iron and lower content of sodium in gram, makes this flour a good alternative to chickpea or other GF flour to develop healthier food products. Amaranth flour had a high protein digestibility, while tiger nut and millet flours were less digestible. Gram, chickpea, quinoa, buckwheat, and oat flours fulfilled amino acids recommendation for daily adult intake showing no limiting amino acid. Total polyphenolic content and antioxidant capacity showed higher values for buckwheat, followed by quinoa and maize flours. Gram, chickpea, maize, and quinoa flours are good candidates to improve health conditions due to lower saturated fatty acid content. The findings of this study provide useful insights into GF flours and may contribute to the development of novel gluten-free products like bread, cookies, or pasta.

BACKGROUND During the industrial production of β‐glucan, a protein‐rich fraction remains as a by‐product. Recovery of this protein as oat protein concentrate (OPC) results in a source of cereal protein for food and improves the overall economy of the process. In this study, a yoghurt‐type product is developed by lactic acid fermentation of an OPC suspension after subjection to heat treatment to assure starch gelatinization. RESULTS In detail, the process of yoghurt production involved an initial heating step to 90 °C, followed by 24 h fermentation with a starter culture consisting of Lactobacillus delbrueckii subsp. bulgaricus und Streptococcus thermophilus. The resulting yoghurt‐type product was mildly sour (pH 4.2) with a certain amount of lactic acid (3.3 ± 0.2 g kg−1) and contained 4.9 × 106 cfu g−1 lactobacillus after 24 h fermentation. Scanning electron microscopy revealed a porous network presumably built up from the gelatinized starch fraction containing aggregated structures, between which were assumed to be aggregated oat proteins. Moreover, to a limited extent, proteolysis occurred during fermentation. Thus some of the proteolytic enzymes present in the yoghurt culture cleaved oat protein and released peptides. However, the effect on essential amino acids was small. CONCLUSION The results of this study provide a deeper knowledge into the role of starch and protein in fermented OPC yoghurts. The structure of fermented OPC verifies the applicability of oat protein as an alternative source for yoghurt‐type products. © 2019 Society of Chemical Industry