Impact of soluble gas stabilisation (SGS) technology on the quality of superchilled vacuum-packed salmon portions following different cold chain scenarios

The soluble gas stabilisation (SGS) technology involves dissolving CO2 into food at low temperatures before packaging. This study examines the impact of SGS on superchilled vacuum-packed salmon portions under varying cold storage conditions, simulating transport temperatures (Temperature I, 0 or 4°C) and supermarket storage temperatures (Temperature II; 0, 4, and 8°C). The Prepackaging treatment (100% CO2 (SGS) or air (Control)) was conducted in superchilled conditions (-1.6°C) for 10 h. Despite the temperature shifts, SGS Prepackaging treatment significantly resulted in lower aerobic plate counts (APC, P<0.001, F=24.5), psychrotrophic plate counts (PC, P<0.001, F=21.1) and lactic acid bacterial counts (LAB, P<0.001, F=19.56) by extending the microbial lag phases 2.2-3.0 times compared to the controls. The SGS Prepackaging treatment and Temperature II were the main factors that delayed microbiological proliferation. SGS samples, stored at low temperatures, extended the freshness (K-value) of the salmon portions and were less affected by temperature fluctuations than controls. For the content of biogenic amines, cadaverine concentration was most affected, and Temperature II was the main discriminant. Moreover, the fillet colour was minimally impacted by the design variables. However, increased temperatures generally resulted in darker and less reddish fillets. Overall, SGS Prepackaging treatment stabilizes the quality of superchilled vacuum-packed salmon portions under various cold chain scenarios.