Modified atmosphere packaging with a small change in gas ratio could maintain pork quality during −3 °C storage

The use of modified atmosphere packaging (MAP) technology at superchilled temperature in refrigerators may be of great significance in improving meat freshness during storage. This study was to assess the potential benefits of various MAP gas ratios (10% O2/90% N2, 30% O2/70% N2, 20% O2/75% N2/5% CO2 and air) on meat quality during −3 °C storage, which can be applied in a refrigerator. Results showed that the important turning point in the quality change during −3 °C storage is between the 8th and 14th days, and the quality and freshness of pork with no MAP in Group D was the worst of all the groups, which indicated that MAP with a slightly altered gas ratio could better maintain pork quality at the superchilled temperature. Compared with other groups, Group B with 30% O2/70% N2, had the best benefits for sensory evaluation, color and bacterial inhibition, but relatively serious protein oxidation. Thus Group A with 10% O2/90% N2, had the best inhibition effect of protein oxidation, which had benefits in terms of the water-holding capacity and texture of pork and resulted in a high sensory score. This study could provide theoretical guidances for the use of MAP technology at superchilled temperature during meat storage in refrigerators.