Differentiated texture and lipid-lowering effect of cooked pork belly by different cooking regimes: insights from myofibrillar protein aggregation and dissociation, micromorphology

Abstract

The effects of traditional flame stewing (TFS), commercial pressure cooking (PC), and sous-vide cooking (SVC) on the texture of pork belly and the underlying mechanism were investigated. SVC treatment at a low temperature (60 °C) achieved weaker oxidation of sulfhydryl groups, lower α-helical loss, higher surface hydrophobicity, and actomyosin dissociation, which reduced the shrinkage of myofibrils and loss of immobilized water, thus contributed to a tender meat. However, the protein aggregation predominated without actomyosin dissociation during PC treatment, causing the toughening of meat. TFS and PC intensified the atrophy of adipocytes and damage of cell membranes, which helped for the softening of adipose tissue and achieved 13.82% and 17.62 % lipid loss, respectively, and contributed to a higher ratio of polyunsaturated fatty acids to saturated fatty acids (0.45–0.46) than SVC (0.34). Comparisons showed that TFS was a more suitable method to prepare cooked pork belly with tender and juicy texture, low lipid content, and high ratio of polyunsaturated fatty acids to saturated fatty acids. This study offered new insights into how cooking regimes affect the texture and lipid-lowering effects of stewed pork.