Protein Digestibility Assay Kit

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.