Effect of the gas/product ratio and CO² concentration on the shelf‐life of MA packed fish

Abstract

Rainbow t r o u t and Baltic herring fillets were gas packed a t t w o different gas/ product ratios and t w o different COz concentrations. T w o reference samples were used; one frozen and one vacuum packed. Changes in gas composition in the gas packages, microbial and sensory quality, K values and drip formation o f the fillets were investigated during storage at 2°C. A gadproduct ratio o f lOOml/lOOg gas package was as effective as a vacuum package in preserving t h e microbial quality o f fish and a gas/product ratio o f 4 0 m l / l 0 0 g gas package was as effective as a vacuum package in preserving t h e sensory quality of fish.

Effect of vacuum or modified atmosphere packaging (MAP) in combination with a CO 2 emitter on quality parameters of cod loins ( Gadus morhua )

“…This was as expected, based on previous documentation of the bacteria inhibitory effect of CO 2 and that SPB is regarded as sensitive to CO 2 (Devlieghere et al, 1998;Dalgaard, 1995;Hansen, Mørkøre, Rudi, Rødbotten et al, 2009;Hansen et al, 2007;Hansen, Mørkøre, Rudi, Langsrud, & Eie, 2009;Hovda et al, 2007). However, as reported by Randell et al (1995) a low g/p ratio (1/1 and 0.4/1) inhibits bacterial growth similar to vacuum, whereas in the presented study the g/p ratio of 1.6/1 showed a better antibacterial effect compared to vacuum packaging during storage (p = 0.000). However, the "Vacuum + CO 2 emitter" showed a similar inhibitory effect compared to "MAP".…”

“…Devlieghere and Debevere (2000) showed increased concentration of dissolved CO 2 by increasing g/p ratio from 1/1 to 2/1. However, others have reported low g/p ratios of 1/1 or 0.4/1 resulted in similar bacterial inhibition as vacuum packaging of the fish (Randell, Ahvenainen & Hattula, 1995). Furthermore, the initial bacterial load of the fillet product at time of packaging in addition to the level of CO 2 (gas mixture in headspace of the package) and storage temperature, are also crucial for the effect on quality preservation of MAP (Farber, 1991).…”

Effect of modified atmosphere packaging and superchilled storage on the shelf-life of farmed ready-to-cook spotted wolf-fish (Anarhichas minor)

“…A gas to product (G : P) ratio of 1 : 1 was used, also found sufficient for shelf-life extension by others. 23 Higher G : P ratios (2 : 1 or 3 : 1) have been recommended to avoid packaging collapse, 24 but this has a negative effect in taking more storage space. After 4 days the CO 2 level was reduced to 27.9 ± 2.4% and 29.2 ± 1.4% for storage at −1°C and 4°C, respectively.…”

Use of modified atmosphere in seafood preservation

“…In food presenting high moisture and/or fat amounts, such as fish, beef and poultry, the excessive absorption of CO 2 may lead to a phenomenon known as "packaging collapse" (Parry, 1993). Increase in dripping is caused by the dissolution of gases on the muscles surface in atmospheres containing high CO 2 levels (>60%), reduced pH and, consequently, low protein water retention ability (Parry, 1993;Randell et al, 1995). As a consequence, high CO 2 concentrations promote organoleptic changes as, for example, texture alterations in meat.…”