Antioxidant and Techno-Functional Properties of Autoclave-Assisted Pigeon Pea (Cajanus cajan L. Millsp.) Protein Hydrolysate and Its Application as a Functional Co-Binder in Chicken Meatballs

Protein binders play a crucial role in determining the quality of emulsified meat products, such as chicken meatballs. Soy protein isolate (SPI) is widely used as a protein binder; however, its production in Indonesia relies predominantly on imported soybeans, underscoring the need to explore alternative protein sources derived from locally available legumes. This study investigated the effects of autoclaving on the antioxidant and techno-functional properties of pigeon pea (Cajanus cajan L. Millsp.) protein hydrolysates (PPHs) and evaluated their potential as a partial substitute for SPI in chicken meatballs. Based on the overall performance across the evaluated antioxidant and techno-functional properties, including DPPH radical-scavenging activity, reducing power, water- and oil-holding capacities, and emulsifying activity and stability, autoclaving at 121 °C for 15 min was selected for subsequent application. Incorporation of PPH into chicken meatballs affected their physical and sensory properties, with increasing PPH proportions resulting in darker color and lower hardness. Despite these changes, the 75:25 PPH:SPI formulation showed overall sensory acceptability comparable to the SPI-only formulation. Overall, autoclaving modified pigeon pea protein and improved several antioxidant and techno-functional properties, supporting its potential as a multifunctional co-protein ingredient for meat-based food formulations and providing a value-added application for an underutilized legume.