In Vitro Crude Protein Digestibility of Insects: A Review

Abstract

The high protein content of insects has been widely studied. They can be a good food alternative, and therefore it is important to study the effect of digestion on their protein. This review examines the different in vitro protein digestibility methodologies used in the study of different edible insects in articles published up to 2021. The most important variables to be taken into account in in vitro hydrolysis are the following: phases (oral, gastric and intestinal), enzymes, incubation time and temperature, method of quantification of protein hydrolysis and sample preprocessing. Insects have high digestibility data, which can increase or decrease depending on the processing of the insect prior to digestion, so it is important to investigate which processing methods improve digestibility. The most commonly used methods are gut extraction, different methods of slaughtering (freezing or blanching), obtaining protein isolates, defatting, thermal processing (drying or cooking) and extrusion. Some limitations have been encountered in discussing the results due to the diversity of methodologies used for digestion and digestibility calculation. In addition, articles evaluating the effect of insect processing are very limited. It is concluded that there is a need for the standardisation of in vitro hydrolysis protocols and their quantification to facilitate comparisons in future research.

Exploiting Locusta migratoria as a source of bioactive peptides with anti-fibrosis properties using an in silico approach

“…Edible insects have been proposed as an environmentally and economically sustainable source of protein, and are considered as an alternative food, especially to meat. 1 Although their nutrient composition is affected by several factors (e.g., species, sex, developmental stage, habitat, diet, type of processing and preparation), when compared to common meats, edible insects generally contain higher percentages of highly digestible proteins [2][3][4] containing all essential amino acids in adequate proportions for human needs. 1 Insects can be obtained from nature or they can be reared.…”

Factors affecting the decision-making process of using insect-based products in animal feed formulations

“…Even if several studies using insect-based products also assessed diet digestibility, data regarding the ADC of the single insect-based products are quite limited (fish: Basto et al, 2020;Fontes et al, 2019;Gasco et al, 2022;Mo et al, 2019;poultry: De Marco et al, 2015;Mwaniki et al, 2020;Schiavone et al, 2017;pigs: Tan et al, 2020). In vitro protocols have also been assessed (Kovitvadhi et al, 2019;Rodríguez-Rodríguez et al, 2022). Overall, the insect meals have been reported to display good to high nutrient digestibility in all monogastric animals, with ADCs for DM ranging from 61.7 to 95.8 in fish, 53.0 to 77.6 in poultry, and 78.8 to 95.9 in pigs, CP from 58.3 to 92.4, 51.0 to 84.8, and 77.3 to 89.6, respectively, and EE from 82.4 to 98.8, 88.0 to 99.0, and 78.0 to 89.8, respectively (Lee et al, 2022).…”

Comparative Assessment of Insect Processing Technologies for Sustainable Insect Protein Production

“…Satisfying the quality standards related to insect protein digestibility for animal feed holds utmost importance. However, an even more crucial factor is to ensure food safety [11]. The first step in obtaining edible insect products is to harvest and separate them from the residues, followed by their killing and washing [12].…”