Evaluation of Physicochemical and Textural Properties of Emulsified Pork Model Sausages Treated with Rhynchosia nulubilis Powders from Different Drying Methods

Objective: This study aimed to evaluate the effects of Rhynchosia nulubilis powder (RNP) processed by different drying methods on the physicochemical and textural properties of emulsified pork model sausages (EPMSs). Methods: RNP was prepared by freeze-drying (FP), oven-drying (OP), or obtained as a commercial powder (CP), and incorporated into EPMSs at levels of 1.0% and 3.0%. A control without added protein (CTL) and a reference formulation containing soy protein isolate (REF) were included for comparison. Product pH, color, water-holding capacity (cooking loss and expressible moisture), proximate composition, and texture profile parameters were evaluated. Results: RNP addition influenced pH, color, water-holding capacity, and textural characteristics of EPMSs. FP- and OP-treated samples exhibited reduced cooking loss and expressible moisture compared with CTL and CP, indicating improved water-holding capacity, particularly at the 3.0% level. Protein content slightly increased in RNP-treated groups, with the highest values observed in the 3.0%-FP treatment. Redness decreased, while yellowness increased with RNP addition, depending on processing method and concentration. Textural properties, including hardness, cohesiveness, gumminess, and chewiness, were enhanced in FP and OP treatments, whereas CP showed limited improvements. Conclusion: The results demonstrate that RNP processed by freeze- or oven-drying effectively enhances the quality and functional properties of EMPSs. Properly processed RNP may serve as a promising non-meat protein ingredient for improving water retention and texture in processed meat products.