The Role of Ohmic Heating in Tailoring Pea Protein Functionality

TL;DR

Ohmic heating improves pea protein's foaming and gel properties, making it more useful for plant-based food products.

Contribution

Ohmic heating is introduced as a novel method to enhance pea protein functionality for food applications.

Findings

Ohmic heating reduced pea protein particle size, improving foaming capacity by 40%.

Cold-set gels from ohmically heated pea protein were softer but more homogeneous.

Emulsifying activity remained unchanged despite structural modifications.

Abstract

Plant-derived proteins have been growing in interest for the design of innovative foods and ingredients following the trend of animal protein substitution. These proteins display interesting functional properties, including emulsifying, foaming, and gelling capacity. Unfortunately, commercially available plant protein ingredients often present limited functionality due to the modifications induced during production. In this study, ohmic heating (OH) was evaluated as a physical modification strategy to enhance the functionality of commercial pea protein (PP). PP dispersions were subjected to OH at 100 °C, 130 °C, and 150 °C, and their physicochemical, foaming, emulsifying, and gelling properties were assessed. OH processing significantly reduced mean particle size, with the surface-area weighted diameter (D(3,2)) decreasing from approximately 76.1 µm in untreated PP to 56.5, 31.1, and 10.6 µm after OH at 100, 130, and 150 °C, respectively. These structural changes resulted in a clear improvement in foaming performance, with foaming capacity increasing by approximately 40% compared to the control, while all foams remained stable for at least 60 min. In contrast, emulsifying activity showed no substantial enhancement. Cold-set gels prepared from OH-treated PP exhibited significantly altered rheological behavior, characterized by lower complex modulus values (G* ≈ 0.8–5.4 kPa at 1 Hz) compared to the untreated PP gel (≈25.2 kPa), indicating the formation of softer yet more homogeneous gel networks. Overall, the results demonstrate that OH is an effective tool to tailor the functional properties of commercial pea protein, particularly by enhancing foaming performance and modulating gel structure, supporting its potential application in the development of novel plant-based food products.

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