A review on amaranth protein: composition, digestibility, health benefits and food industry utilisation

Amaranth grains are a source of proteins such as albumins and globulins with well-balanced amino acids profile since they are rich in lysine and methionine, which are scarce in other cereals. Amaranth proteins also show a great bioavailability that contributes to their high quality and, consequently, become a potential substitute for animal-based foods. This review aims to provide a comprehensive summary of the recent research on screening of amaranth proteins as well as their isolation, fractionation, amino acid composition and digestibility. In addition, we carried out an important overview of the nutritional benefits of amaranth proteins and its application as ingredients in food systems. The amaranth has an excellent balance of amino acids and bioactive peptides, with potential health benefits. The consumption of amaranth proteins can promote human health due to their potential to reduce the risk of suffering chronic diseases, while their bioactive peptides play a fundamental role as antioxidant, anti-inflammatory, anti-hypertensive and antimicrobial activities. This review makes an important contribution and approaches the potentiality of using amaranth as a plant protein source, addresses its digestibility and the beneficial health effects brought mainly by the bioactive peptides present in grains.