True ileal amino acid digestibility and digestible indispensable amino acid scores (DIAASs) of plant-based protein foods

• Published in: Food chemistry Vol. 338; pp. 128020 - 7
• Main Authors: Reynaud, Yohan, Buffière, Caroline, Cohade, Benoît, Vauris, Mélissa, Liebermann, Kevin, Hafnaoui, Noureddine, Lopez, Michel, Souchon, Isabelle, Dupont, Didier, Rémond, Didier
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.02.2021; Elsevier
• Subjects: Amino Acids - analysis; Amino Acids - metabolism; Amino Acids, Essential - analysis; Amino Acids, Essential - metabolism; Animals; DIAAS; Dietary Proteins - pharmacokinetics; Digestibility; Digestion; Food and Nutrition; Food matrix; Glycine max - chemistry; Ileum - drug effects; Ileum - metabolism; Life Sciences; Nutritive Value; Pea; Plant protein; Plant Proteins - metabolism; Plant Proteins - pharmacokinetics; Soy Foods; Soy Milk; Soya; Swine; Swine, Miniature; Triticum - chemistry; Wheat; Soya; Food matrix; Plant protein; Pea; Wheat; DIAAS; Digestibility
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128020

•Proteins of seitan, tofu, soya milk and pea emulsion are highly digestible.•Seitan protein quality is low because of the low lysine content of wheat protein.•Its low sulphur-containing amino acid content limits pea emulsion protein quality.•The protein quality of commercial soya milk and tofu is high.•Soya proteins have higher nutritional quality in soya milk than in tofu. Plant-based protein foods are increasingly common, but data on their nutritional protein quality are scarce. This study evaluated it for seitan (wheat-based food), tofu (soya-based food), soya milk, and a pea emulsion. The true ileal digestibility (TID) of their amino acids was determined in minipigs, to calculate the digestible indispensable amino acid score (DIAAS). The TID of the proteins was high and not significantly different between the foods tested: 97% for seitan, 95% for tofu, 92% for soya milk and 94% for pea emulsion. There were only minor differences in individual amino acid TIDs. DIAAS ranking was thus essentially driven by the amino acid composition of the food: soya-based food > pea emulsion > seitan. Nevertheless, the lower TID of sulphur-containing amino acids in tofu than in soya milk induced a significant decrease in DIAAS (from 117% to 97%), highlighting the importance of the matrix effect on nutritional protein quality.