Effect of vacuum cooling on stability of macro-porous sausage during refrigerated storage-Vacuum-cooled sausage has a longer shelf life.

In this study, two types of cooling methods (vacuum cooling and air cooling) were used to cool cooked macro-porous sausage. Alterations in the microbiological conditions, pH, instrumental color (*, * and *), total volatile nitrogenous bases (TVB-N), lipid oxidation (TBARS), water activity (aW), moisture content, and texture indicators were evaluated to determine sausages' quality changes during storage under refrigeration for up to 10 days. In general, the shelf life of sausages chilled by vacuum cooling (8 days) was similar to that of sausages cooled by air cooling (9 days). For pH, no significant difference ( > .05) was obtained between two cooling methods. However, vacuum-cooled sausages have lower * value ( < .05), lower moisture content, and water activity compared with the air-cooled sausages. However, sausages cooled by vacuum cooling showed a sharp increase in TBARS and TVB-N values but maintained texture characteristics for a longer time compared with air-cooled sausages. Although the results indicated that the quality of sausages treated by those two methods remarkably decreased after 7 days, characteristics of sausages cooled by vacuum cooling are better within accepted standards compared with air-cooled sausages. In conclusion, vacuum cooling can be a feasible cooling method with great potential to be used in cooked macro-porous sausages to maintain the quality and may provide reference experiences for the food with similar structure.