033: Effect of Proanthocyanidin and Whey Protein Interactions on the Functionality of Meat Alternatives

Introduction

The increasing consumer demand for alternative proteins has led to the exploration of novel ingredient combinations that enhance nutritional and functional properties. Whey protein isolate (WPI), a high-quality source of essential amino acids, is a by-product of cheese production and offers potential for upcycling in food applications. Proanthocyanidins (PA), also called condensed tannin, are natural polyphenolic compounds known for their antioxidant capacity and protein-binding properties. We hypothesize that the interaction between whey protein and proanthocyanidins can enhance the functional properties of whey protein, leading to improved stability and functionality in food applications. This research aims to determine the effect of sorghum PA on the rheological properties, molecular weight (MW) and stability of WPI.

Methods

PA extracted from sorghum using 70% (v/v) acetone was incorporated with whey protein (0-50 mg PA/g WPI) to form WPI-PA complexes and then treated with ebeam irradiation (EBI) at (0-10kGy). Additionally, the complexes were heated at 80°C under different pHs (5, 7 and 10) to further explore the effect of processing conditions. The rheological properties were analyzed using a rapid visco analyzer (RVA) and rheometer, whereas molecular weight characterization was determined using SEC-MALS and SDS-PAGE.

Results

Incorporating WPI with PA at 25 mg/g showed an increase in viscoelastic properties from 23.1% to 42.4% compared to the control, suggesting improved gel stability with PA addition. Treating WPI-PA complexes with EBI (2-10 kGy) resulted in an increase (10-20%) in high MW (1.106 x 105 kDa) compared to the control (7.67 x 104 kDa), indicating an interaction between WPI and PA, resulting in a clear complex. SDS-PAGE showed a distinct band at ~400 kDa, confirming the interaction of WPI-PA complexes under EBI. Heating complexes at pH 7 show an increase in MW (4.203 x 105 kDa) compared to the control (1.041 x 105 kDa), indicating heat-induced interactions between WPI and PA.

Significance

The current finding suggests that WPI MW and functional properties can be modified via complexation with PA under different processing conditions. This suggests that PA can expand WPI applications in products such as meat alternatives.

Authors: Muhammad B. Haider, Mian N. Riaz, Joseph M. Awika