Plant protein adsorption at oil–water interfaces: A mapping review using alternate subphase tensiometry

Abstract

Plant proteins are rapidly emerging as functional food ingredients as a more sustainable and ethical alternative to established animal proteins, e.g., for the interfacial stabilization of emulsions and foams. To date, there is a large knowledge gap between plant and animal proteins, and it is often difficult to predict the interfacial performance of novel plant proteins, their individual fractions, and behavior as a function of processing conditions. Here, we introduce alternate subphase tensiometry (AST) as a novel method to map literature data on interfacial tension reduction of novel protein sources. We collected, compiled, and reanalyzed interfacial tension literature data from pea, soy, chickpea, lentil, faba bean, wheat, and microalgae protein. AST allows standardized plotting of literature data in uniform graphs, providing a rapid overview of the present data and pinpointing current gaps. Furthermore, grouped data can be readily singled out to identify promising protein fractions and effects of processing conditions such as pH, ionic strength, or pretreatments. Hence, AST is a powerful tool to summarize the existing data landscape, identify research gaps and particularly promising protein fractions, and ultimately predict the interfacial performance of plant proteins for interfacial stabilization of emulsions and foams.