Thermal sterilization is widely adopted in peanut protein beverage processing, and may cause Maillard reaction (MR). This paper was designed to research the effect of thermal sterilization induced MR on the subsequent simulated gastrointestinal digestion. Peanut protein isolate (PPI) and glucose (1:1) were heat-treated in 80/100/121 oC for 30 min, then subjected to a simulated gastrointestinal digestion to evaluate the digestion characteristics. PPI without glucose, as a control group, was dealt in the same conditions. Absorbance in 294/420 nm of heat-treated samples and degree of hydrolysis (DH), protein digestibility (PD), molecular weight distribution, free amino acid composition of simulated gastrointestinal digestion products were measured. The experimental results showed that: compared to the control group, PPI heat-treated with glucose caused stronger MR. Heat treatment and MR leaded to an increase of larger molecular weight peptides content. Only heat-treated in 121 oC for 30 min had contributed to the DH increase of simulated gastrointestinal digestion products, and from a general view, MR gone against the digestive and utilizable performance of PPI.
