Effects of freezing methods and frozen storage on physicochemical, oxidative properties and protein denaturation of porcine longissimus dorsi

• DOI: 10.1016/j.lwt.2021.112529
• Publication Date: 2021-09-27T13:56:41Z
• Authors: Mingming Zhu; Juan Zhang; Lingxia Jiao; Changming Ma; Zhuangli Kang; Hanjun Ma
• Keywords: 0404 agricultural biotechnology; 04 agricultural and veterinary sciences; 0405 other agricultural sciences

Abstract Changes in physicochemical properties, oxidative properties, and protein denaturation of porcine longissimus muscles, which were frozen by different methods and then stored at −18 °C for various times, were investigated. As the freezing rate was increased, the deterioration was reduced. In addition, over a period of 168 d, the quality reduction was proportional to the levels of oxidation and protein denaturation. The obtained results showed that a slower freezing rate and long-term duration had a negative influence on the porcine quality. At 168 d, although the thawing loss, total volatile base nitrogen, and electrical conductivity of the −40 °C frozen samples were higher than those of the −80 °C and liquid nitrogen frozen samples, they remained within the acceptable limits. However, compared with freezing at – 18 °C, freezing at −40 °C reduced oxidation, and maintained the sample thermal stability and viscoelasticity. Therefore, in terms of energy conservation, freezing at −40 °C could preserve porcine quality over 168 d, thereby confirming its suitability for application in the meat industry.