High-pressure homogenization improves functional properties of pea protein isolates

Abstract

The growing demand for sustainable plant-based proteins has led to intensified efforts to enhance their functional performance in food systems. This study systematically investigated the effects of high-pressure homogenization (HPH) on the functional properties (techno-functional and physico-chemical characteristics, in vitro digestibility) of two distinct commercial pea protein isolates (PPI). Protein dispersions were subjected to HPH at pressures of 60 MPa and 120 MPa, using either one or three passes. HPH significantly reduced particle size by disaggregating large protein aggregates, leading to smaller and more soluble particles. At pH 7, protein solubility rose by up to 142% (PPI 1) and 158% (PPI 2), with pronounced improvements in emulsifying properties and foaming activity. Consistent with this, water binding capacity declined markedly. Although higher pressure enhanced techno-functional properties, the number of passes exerted an even stronger influence than pressure alone. Mild HPH-treatment improved gelation in one of the two pea protein isolates. In vitro digestibility, however, remained unaffected. The untreated PPI differed in their techno-functional properties and responded differently to HPH. This suggests that the initial characteristics, which are likely shaped by the intensity of the processing during protein isolation, play a decisive role in HPH responsiveness. Principal component analysis confirmed these raw material-specific differences and showed that HPH-treatment significantly altered the functional profile compared to the untreated samples. Overall, integrating HPH during protein production or as an in-line step in manufacturing offers a scalable, cost-effective route to tailor functionality in liquid applications such as dairy alternatives and beverages.