In the storage and processing of meat products, lipid hydrolysis is an important factor affecting the quality and flavor of meat products. Lipid hydrolysis occurs mainly due to the action of lipase, and different endogenous lipase acts on different sites of the lipid molecule to form a variety of products such as aldehydes, alcohols, esters and hydrocarbons, which greatly affects the flavor of meat products. Proper lipid hydrolysis is conducive to improving the flavor of meat products, but excessive lipid hydrolysis will lead to a decrease in the quality of meat products, protein oxidation and rancid odor. Furthermore, there is a correlation between lipid hydrolysis and lipid oxidation, and free fatty acids formed by lipid hydrolysis can be oxidized, resulting in a decrease in the quality and flavor substances of meat products. Controlling the degree of lipid hydrolysis is conducive to improving the quality of meat products and determining conditions that are more conducive to the preservation and processing of meat products. Lipid hydrolysis has a greater impact on unsaturated fatty acids, and the action of lipase on lipid has attracted the attention of many scholars. This paper reviews the mechanism of lipid hydrolysis in meat and meat products, and the resulting chemical changes as well as the influence of lipid hydrolysis on the quality and flavor of meant and meat products.

Lipids are important constituents of organisms. The type, structure and amount of lipids in meat can be investigated by various techniques such as mass spectrometry (MS), providing the basis for understanding the role that different lipids play in meat products. With the support of modern technology, the influence of lipidomics in meat research has gradually increased. Lipidomics allows visual understanding of the influence of lipids on meat quality and flavor, which has been increasingly applied in meat quality research by determining marker lipids. This paper summarizes recent research on the effect of different classes of lipids on meat quality, and reviews the application of lipidomics in meat research.

In this work, the effect of inactivation of enzymes on the salting quality of yellow-feathered broiler meat was addressed. The changes in the salt diffusivity (saltiness taste), umami taste, water retention properties (cooking loss, centrifugal loss and hydration capacity), water distribution, texture (hardness, chewiness, elasticity and viscosity) and microstructure of chicken meat were examined after salting. Hot meat and pre-cooled meat were considered as controls. The results showed that the salt diffusivity in chicken with enzyme inactivation was intermediate between that of hot meat and pre-cooled meat, whereas the umami taste was stronger than that of the controls. The cooking loss and centrifugal loss of chicken meat with enzyme inactivation were significantly reduced after salting, and the hydration capacity increased. Further investigation showed that lower mobility of bound water and immobilized water in chicken with enzyme inactivation contributed to higher water retention capacity. The hardness and chewiness of chicken meat with enzyme inactivation were significantly higher compared with the controls. The diameter of muscle fibers initially increased and decreased later with increasing salt concentration.

Heating is a common way of processing meat and meat products. Proper heating can improve the color and flavor, kill harmful microorganisms and parasites, extend the storage period, and improve nutrient digestion and absorption, but excessive heating will lead to the oxidation of unsaturated fatty acids in meat and promote the formation of harmful lipid oxidation products, thereby reducing the nutritional value of meat and affecting its food safety. This paper summarizes the recent advances in understanding the effect of lipid oxidation on meat flavor, introduces the mechanism of lipid oxidation, and summarizes the influence of heating temperature, time, method and additives on lipid oxidation in meat and meat products and the corresponding countermeasures. We anticipate that this review will provide a theoretical reference for lipid oxidation control in meat processing.

To investigate the difference in the comprehensive quality of free amino acids (FAA) in crayfish meat from different co-culture modes, the FAA composition of crayfish tail meat from three representative co-culture modes in Xinghua city of Jiangsu province was determined, and the contribution of FAA to the taste of crayfish meat was evaluated by computing the taste active value (TAV). Comprehensive evaluation of FAA in crayfish meat was performed using principal component analysis (PCA) and cluster analysis. The results showed that 17 amino acids were found in crayfish meat from each co-culture mode, and the total amount of FAA was 21.80–27.11 mg/g. Arginine (Arg) was the most abundant FAA in all samples, accounting for 55.64%–67.76% of the total FAA, which was much more abundant than the other amino acids. Moreover, Arg contributed the most to the taste of crayfish meat. The TAV of the sweet amino acid alanine (Ala) and the bitter amino acid histidine (His) in crayfish were greater than 1 for all co-culture modes, indicating that both amino acids contributed to the taste of crayfish meat. The TAV of glutamic acid (Glu) as the amino acid with the strongest umami taste was greater than 1 only in crayfish meat from rice-crayfish mode with one-rice and two-crayfish in a field (RC2). Three principal components were extracted for the 17 amino acids, which cumulatively explained 89.937% of the total variance and could reflect the comprehensive information of amino acids in crayfish meat. The results of PCA showed that RC2 ranked first, and crayfish-crab mode (CC1) ranked last. The hierarchical cluster analysis divided crayfish meat from different co-culture modes into three categories. Similar results were obtained by PCA. This study demonstrated that the comprehensive quality of FAA in crayfish from rice-crayfish co-culture mode was better than that in crayfish from the other co-culture modes.

Water-holding capacity, texture and color are important indicators of fresh meat quality. In China, drip loss and textural deterioration of fresh meat are critical problems in the meat industry, causing greater quality loss than that in developed countries. Recently, researchers have identified a series of potential biomarkers for the water-holding capacity and tenderness of meat and have studied the effect of cell apoptosis on meat tenderness. However, the relationship between ferroptosis and fresh meat quality has been researched little. After slaughter, the intramuscular environment alters and ferroptosis occurs, which is characterized by the accumulation of iron, an increase in lipid oxidation and disruption of redox equilibrium. These changes are closely related to meat quality. This paper reviews the characteristics, metabolic pathways and regulatory mechanisms of ferroptosis, and the crosslinks between ferroptosis and other modes of cell death. Moreover, it elaborates on how ferroptosis affects fresh meat quality through iron homeostasis imbalance, redox imbalance and lipoperoxidation. Overall, this review provides deeper insights into the mechanism of meat quality formation during postmortem aging.