Deep freezing to maintain the freshness of pork loin during long-term storage.

As storage temperature impacts frozen meat quality, we evaluated the ideal freezing and storage temperatures for pork loin, and effects of long-term storage at - 60, - 50, and - 18 °C on pork loin physicochemical properties. Pork loin was cut into 30 × 30 × 30 mm (50 g) and packed in air-containing box. Thereafter, they were stored at different freezing temperature for 6 months. Frozen pork loins were thawed at 4 °C. Samples frozen at - 18 °C exhibited surface dehydration (at 3 months) and high moisture loss surface dehydration-induced discoloration and toughening. However, samples frozen by deep freezing temperature (- 60 and - 50 °C) had lower values of thawing loss, WHC, and shear force than those of frozen at - 18 °C. Samples frozen at - 60 and - 50 °C maintained their freshness better than those frozen at - 18 °C; samples stored at - 60 °C showed significantly lower VBN than those stored at - 50 °C. Therefore, - 60 °C is suitable for freezing pork loins.