Amino acids and protein in vitro bio-accessibility from edible insect and pea protein enriched bread

Abstract

Edible insects have seen increasing use as a nutritive ingredient in food because of their high protein content and digestibility of amino acids from insect-enriched food. Therefore, the aim of this work was to evaluate amino acids and proteins bio-accessibility in bread enriched with Alphitobius diaperinus and Tenebrio molitor, comparing with a control and pea protein enriched bread. Bread was enriched at 5 and 10% with experimental ingredients. Experimental bread and the control were subjected to standardised static in vitro gastrointestinal digestion. Total amino acids (TAA) of breads were determined before digestion and free amino acids were determined after digestion by high-performance liquid chromatography. Crude protein was determined before and after gastrointestinal digestion. Incorporating pea protein, A. diaperinus, and T. molitor powder in bread formulations showed higher essential amino acids and non-essential amino acids content (12.170-16.274 mgTAA/100 g) than the control bread (10.843 mgTAA/100 g), with increasing amino acids content when concentration in bread increased. Bio-accessibility of each amino acid varied as a function of the bread formulation, however, after in vitro gastrointestinal digestion, experimental bread showed higher accessible amino acids and protein content than the control bread.