Mechanism insights into NaCl-regulated molecular aggregation and crosslinking during Antarctic krill (Euphausia superba) surimi gelation: A comparative study with Litopenaeus vannamei

NaCl regulates the aggregation-crosslinking balance of AK proteins during gelation. • A balanced two-stage aggregation ratio (∼0.85) yields the optimal gel texture. • Excessive NaCl (>3.0%) induces premature aggregation that impairs gel networks. • AK proteins show higher salt–heat sensitivity in thermal-aggregation than LV. Antarctic krill ( Euphausia superba ) represents a vast yet underutilized marine protein resource; however, its inherently weak and unstable gelation properties hinder its broad industrial application. The primary objective of this study was to systematically investigate how NaCl (1–3.5%, w/w) modulates protein aggregation and crosslinking during the thermal gelation of Antarctic krill surimi. Using Litopenaeus vannamei as a reference, a multi-scale analysis showed that 2.5% NaCl produced optimal gel texture (2.56 N for Antarctic krill; 25.84 N for Litopenaeus vannamei ). Rheology revealed a three-stage gelation process with stronger elastic reinforcement in Litopenaeus vannamei . AFM analysis demonstrated that NaCl promoted protein aggregation during two-stage heating, with more pronounced aggregation observed in krill proteins. An aggregation efficiency of ∼0.85 yielded the best gel performance, underscoring that network formation benefits from progressive aggregation dynamics rather than runaway cluster growth. These findings provide a theoretical basis for enhancing the quality of krill-based foods. Download: Download high-res image (462KB) Download: Download full-size image