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The Comparison of Functional and Physical Properties of Commercial Pulse Proteins to Soy Protein

There has been growing interest in the utilization of plant-derived proteins as functional ingredients in many food and beverage applications because they are perceived as being more sustainable, healthy, and ethical than animal-derived proteins by many consumers. Traditionally, soy proteins have been the most widely employed plant protein in the food industry. However, a number of alternative plant-based protein sources have recently become available, with pulse proteins being one of the most popular. In this study, the physicochemical properties and functional attributes of various commercially available pulse protein isolates were compared with those of soy protein isolate to evaluate their potential application in foods and beverages. The water holding capacity, oil holding capacity, gelation properties, emulsifying properties, and color of faba bean (FPI), pea (PPI), lentil (LPI), and soy (SPI) protein isolates were therefore measured. SPI had a significantly higher water holding capacity (7.6 g/g) than the pulse protein isolates (2.2-5.1 g/g). Among the plant protein isolates, PPI had a significantly lower oil holding capacity and gelling property. LPI was more effective at producing small oil droplet sizes during homogenization than the other protein isolates. Nevertheless, all of the plant proteins were capable of forming relatively small oil droplets (D32 = 1-3 mm) at a protein-to-oil ratio of 1:10. As expected, droplet size decreased with increasing protein concentration for all plant protein isolates, which increased their resistance to creaming. These results suggest that pulse proteins may have similar or better techno-functional properties than soy proteins for certain applications. In particular, lentil proteins were more effective emulsifiers, whereas faba bean proteins were more effective gelling agents. These proteins may therefore be suitable for application in plant-based milks, eggs, cheese, or meats where emulsifying or gelling properties are required.