Effect of salt on CO2 solubility in salmon (Salmo salar L) stored in modified atmosphere

Abstract

Salt and CO2 in the form of modified atmosphere (MA) packaging are often used forms of preservation of seafood, as they both are known for their ability to reduce spoilage and health risks. However, little is known regarding interaction between the two when applied to seafood. Hence this experiment investigated CO2 solubility in salmon injected with various brines and packaged using MA packaging or soluble gas stabilization (SGS) followed by MA packaging. Regardless of packaging method, increasing NaCl concentration decreased the absorbed CO2 concentration, as seen from analysis of head space composition, calculations of Henry's constant, and absorbed amount of CO2 within the product. However, the effect was only significant after long storage, as no effect of NaCl was observed in the samples before MA packaging in retail trays. Furthermore, use of SGS significantly increased amount of absorbed CO2 as compared to regular MA packaging. The effect of SGS outnumbered the negative effect of NaCl, thus making the use of both NaCl and CO2 possible without losing effect of either.