Strategies to improve the emulsification properties of rice proteins as a promising source of plant-based emulsifiers: An updated mini-review

Rice and its by-products are an under-utilized resource of high-quality and sustainable plant protein. Due to their characteristics of hypoallergenic, gluten-free, and balanced amino acid composition, rice proteins (RPs) are considered to be more important than other grain proteins and have great potential to compensate for the defects of animal proteins. In particular, the application of RPs in plant-based emulsifiers has attracted much attention in recent years. Nevertheless, the inappropriate molecular structure and excessive molecular weight challenge their potential industrial value in food emulsions. This review summarizes the effective strategies to improve the emulsifiability of RPs by relevant modifications with an emphasis on the current scientific knowledge and future perspectives. These modifications could mainly be achieved by enzymatic hydrolysis, combination with polyphenols or polysaccharides. Meanwhile, some physical processing techniques including microwave, ultrasound, and high pressure and chemical strategies such as pH-shifting, fibrosis, phosphorylation, and alkylation have also started to rise.