Heat-Induced Gelation of Myofibrillar Protein in Litopenaeus vannamei: Functional Characteristics and Molecular Interactions During Sous Vide Processing

This study investigated the regulatory effects of sous vide (SV) processing on the functional properties of myofibrillar protein (MP) from Litopenaeus vannamei , to elucidate the potential mechanism underlying heat-induced MP gel formation during SV processing. Results showed that SV processing initially enhanced the interfacial properties and in vitro digestibility of MP. Specifically, initial thermal induction induced the unfolding of MP, enhancing protein flexibility, boosting surface activity, and exposing enzyme-accessible binding sites. Conversely, with increasing SV processing temperature and duration, exacerbated protein oxidation and denaturation induced MP aggregation, which in turn led to a subsequent decline in these functional properties. Fourier Transform Infrared spectroscopy (FTIR) further validated these observations, revealing that the α -helical content of the protein’s secondary structure initially decreased before increasing, with a concurrent increase in β -sheet content. Furthermore, molecular dynamics (MD) simulations revealed that the protein exhibited improved thermal stability at higher temperatures. • SV enhanced MP’s interfacial properties and in vitro digestibility. • MP’s WHC and OHC generally decreased with elevated SV processing. • In SV, higher temperatures correlate with greater MP aggregation and enhanced gel stability. • SV induced MP conformational deconstruction, reorganization, and aggregation. • Proposed a potential mechanism for SV-mediated MP gel formation.