Unraveling the underlying mechanism: how processing methods alter muscle protein structure and in vitro digestibility of shrimp (Litopenaeus vannamei)

Processing methods affect the muscle quality and digestive characteristics of shrimp. • Post-boiling heating showed different quality changes in different shrimp products. • The order of dry matter digestibility was FB > RFB ≈ FCB > DB. • Free amino group release was fitted using logistic model and a pseudo-first-model. Food processing is a critical factor influencing protein digestibility and nutritional value. With fresh shrimp (F) as the control，the combined effects of three typical processing methods: raw-frozen (RF), cooked-frozen (FC), and dried (D), on the muscle quality and digestive characteristics of shrimp ( Litopenaeus vannamei ) were systematically investigated. The results indicated that processing methods modulated the final digestibility of shrimp; among the three typical processing methods for shrimp, raw-frozen (RF) treatment best preserved shrimp muscle quality and digestibility, whereas drying (D) altered the muscle quality and impaired protein digestion. Digestive kinetics results indicated that RF treatment maintains higher rates and degrees of digestion. Principal component analysis (PCA) and correlation analyses identified microstructure, texture, moisture state, and myofibrillar protein structure/oxidation as key factors governing digestibility differences among processing methods. This study provides a theoretical basis for the targeted regulation of shrimp processing technologies to optimize nutritional quality. Download: Download high-res image (145KB) Download: Download full-size image