Protein Digestibility Assay Kit

A clean-label process to endogenously glycate and purify pea protein was investigated. The production of maltodextrin from pea starch with a specific dextrose equivalent (DE) was optimized. The produced maltodextrin (14.6 DE) was used to initiate a limited and controlled Maillard-induced glycation of pea protein. The partially glycated pea protein (PG-PP) was subjected to hydrophobic interaction chromatography to remove unreacted carbohydrate, followed by characterization of the purified product. The extent of Maillard-induced glycation was monitored by assessing changes in color, free amino groups, and protein/glycoprotein profiles. The purified PG-PP was evaluated for thermal denaturation, surface properties, protein secondary structure, protein solubility, thermal stability, and digestibility. Maillard-induced glycation was limited to initial stages and resulted in a moderate blockage of amine groups (~30%). The purified PG-PP had a relatively low surface hydrophobicity, a markedly enhanced protein solubility (~90%) at pH 3.4, and a nonimpacted protein in vitro digestibility (~100%). This work provided the impetus needed for future scale-up and process optimization for the production of value-added pea protein ingredient intended for high protein beverage applications.

Insects, especially crickets, have been proposed as a novel source of nutrients in human nutrition since they possess bioactive molecules, including high protein content, lipids, chitin, vitamins and minerals. In this work, the nutritional and functional properties of a novel Italian spray-dried (SD) cricket powder were evaluated. The powder was characterized by physico-chemical properties (morphology, size distribution, solid state, thermal profiles, and surface zeta potential), and antioxidant properties. Moreover, preclinical properties (cytocompatibility and pro-inflammatory immune response) were assessed. The powder was characterized by microparticle structure with bulges and rough surfaces, showing distinctive antioxidant properties. The preclinical results suggested that the SD crickets were biocompatible towards Caco-2 and macrophages without immune response, representing an interesting material for the food industry that could provide health benefits in addition to the basic nutritional value of traditional foods.

A deficit in protein intake can severely halt children growth, and is associated with both structural and functional pathologies of the brain, as well as increase the risk of contracting infectious diseases. Protein-enriched defatted meals from sacha inchi (Plukenetia volubilis) (sdSI) and chocho (Lupinus mutabilis) (sdCH) were obtained by a solvent defatting procedure. The concentration of protein was higher in sdSI (64%) than in sdCH (60%). Lysine and tryptophan were the limiting amino acid (AA) in each case. However, the AA profile of the protein meals met daily intake FAO requirements for adults, while their blends met the requirements for infants. The sdSI had an in vitro digestibility of 100. Regarding functional properties, sdSI presented higher values for water absorption index (3.5), emulsifying activity (56%), and foaming capacity (167%), while the sdCH had a slightly better oil absorption capacity (2.8). However, when mixing sdSI with sdCH some improvements in functional properties were observed. The nutritional and functional properties of the mixtures of meals can be used to develop protein-enriched foods and beverages.

The replacement of animal with plant proteins in human diets has been increasing in recent years. The impact of blending milk protein concentrate (MPC) with protein isolates from soy (SPI), rice (RPI) and pea (PPI) on the in vitro digestibility and antioxidant activity of the resultant blends was investigated. Different plant protein–MPC blends (i.e., SPI–MPC (25:75), RPI–MPC (50:50) and PPI–MPC (25:75)) were analyzed. The lowest protein digestibility corrected amino acid score (PDCAAS) was associated with RPI (0.70), while the blends had PDCAAS values above 1.00 demonstrating the high digestibility of the proteins in the blends studied. An in vitro simulated gastrointestinal digestion was carried out on the samples. The degree of hydrolysis and gel permeation high performance liquid chromatography profiles showed that the SPI–MPC blend was more extensively digested in the gastric phase compared with the two other blends, while the PPI–MPC and RPI–MPC blends were mainly digested during the intestinal phase. The SPI–MPC digested blend had the highest 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity having a half maximal effective concentration (EC₅₀) of 0.10 ± 0.01 mg/mL. The findings show that blends of plant protein with MPC had higher in vitro digestibility and antioxidant activity compared to the individual plant protein isolates.