This laboratory study compared post-gelation pasteurisation at 80°C with sterilisation at 121°C in microbial-transglutaminase-crosslinked threadfin-bream surimi. MTG initially strengthened gels, but sterilisation disrupted the network, increased oxidation/Maillard volatiles and reduced in-vitro digestibility, offsetting much of the crosslinking benefit more than pasteurisation.
Key findings
- MTG increased breaking force and distance and reduced expressible moisture. Pasteurisation maintained/slightly improved non-crosslinked gels but weakened MTG gels. Sterilisation disrupted beta-sheets, weakened hydrophobic interactions, increased disulfide bonding and fragmented structure. TBARS rose after pasteurisation but fell after sterilisation alongside increased volatiles, consistent with malondialdehyde degradation. MTG increased peptide diversity, while heating reduced diversity and digestibility.
Why this matters globally
Ready-to-eat surimi must balance safety, shelf life, texture, aroma and nutrition. The study shows that enzyme and thermal processes cannot be optimised independently, with relevance to global processed-protein manufacturing.
Thai researcher contribution
Suranaree University of Technology and BIOTEC integrated food science, protein structure, microstructure and peptidomics to explain not only whether texture changed but why.
Limitations to consider
One laboratory surimi formulation was studied. In-vitro digestion is not human absorption, and volatiles were not tied to sensory acceptance. Lower TBARS after sterilisation may underestimate oxidation because products degrade. No microbial challenge, shelf-life or industrial energy balance was reported.