Changes of physicochemical and volatile flavor compounds of dry-cured Diqing Tibetan pig hams during fermentation. Food research international (Ottawa, Ont.) This study aimed to explore the flavor formation mechanism of Diqing Tibetan pig hams by investigating changes of their physicochemical and volatile flavor compounds during fermentation (0, 30, 90, 180, 360, and 540d) using amino acid analyzer , texture profile analysis, and gas chromatography-ion mobility spectroscopy (GC-IMS). During fermentation, the hams significantly decreased in moisture and centrifugal loss, while increased in chewiness, hardness, and proteolysis index, with their free amino acids content reaching the maximum at 360d and significantly decreasing at 540d. GC-IMS identified 78 volatile organic compounds, with the highest total content of alcohols and aldehydes at 180d, ketones and heterocycles at 360d, and esters at 540d. PLS-DA screened 24 volatile flavor markers, with aldehyde (2-methyl-2-propenal), ketone (2-heptanone-D), alcohol (3-methylbutanol-D), ester (ethyl3-methylbutanoate-M), and heterocyclic substances (2,3-dimethylpyrazine-M) as the main VFMs at 360d. The unique flavor of 540d Diqing Tibetan pig hams was attributed to their higher content of 3-methyl-2-butenal, 3-(methylthio) propanal, ethyl caproate and 2-butanone. These findings provide a scientific basis for the flavor formation mechanism of hams which favoring the further development processing strategies for Diqing Tibetan pig. 10.1016/j.foodres.2024.115136

Correlation between three glycometabolic-related hormones and muscle glycolysis, as well as meat quality, in three pig breeds. Luo Jia,Shen Yuan L,Lei Gang H,Zhu Ping K,Jiang Zhi Y,Bai Lin,Li Zhou M,Tang Qing G,Li Wei X,Zhang Hua S,Zhu Li Journal of the science of food and agriculture BACKGROUND:The present study aimed to evaluate the correlations among muscle concentrations of three glycometabolic-related hormones (insulin, epinephrine and glucagon), muscle glycolysis and meat quality in representative muscles of either glycolytic or oxidative types. Moreover, the relative glycometabolic-related gene expression was measured. One Western crossbreed DLY (Duroc × (Landrace × Yorkshire)), one crossbreed with half-Chinese native-pig origin DL (Duroc × LiangShan) and one pure Chinese native pig TP (Tibetan pig) were used in the present study. RESULTS:Among the three breeds, DLY had the greatest glucagon and epinephrine (P < 0.01). Compared with DLY, TP and DL had lower lactic acid concentrations, showing lower glycolytic potentials (GP), greater ultimate pH values (P < 0.01) and lower relative expression levels of glycometabolic-related genes (GYS1, PRKAG3 and PKM2). Compared with the glycolytic muscle (musculus longissimus dorsi), oxidative muscle PM (musculus psoas major) had lower glucagon and epinephrine contents, lower GP and better meat quality. The concentration of glycometabolic-related hormones in the muscle had significant correlations with muscle glycolysis, meat pH and lightness. CONCLUSION:The results obtained in the present study imply that glucagon and epinephrine levels could be used to indicate early glycolytic metabolism during postmortem. These findings may be helpful in identifying pork with undesirable quality traits. 2016 Society of Chemical Industry. 10.1002/jsfa.8094

High Altitude Adaptability and Meat Quality in Tibetan Pigs: A Reference for Local Pork Processing and Genetic Improvement. Gan Mailin,Shen Linyuan,Fan Yuan,Guo Zhixian,Liu Bin,Chen Lei,Tang Guoqing,Jiang Yanzhi,Li Xuewei,Zhang Shunhua,Bai Lin,Zhu Li Animals : an open access journal from MDPI The carcass and meat quality traits of pig breeds living at three different altitudes (Yorkshire pigs, YP: 500m; Qingyu Pigs, QYP: 1500m; Tibetan pigs, TP: 2500m) were compared. It was observed that there are obvious differences in pig breeds with respect to performance parameters. Specifically, YP had the best carcass traits, showing high slaughter rates and leanest meat. Conversely, QYP had the highest back fat thickness and intramuscular fat (IMF) content. For the high-altitude breed TP, the animals exhibited low L* and high a* values. The genotypes contributing to the observed phenotypes were supported by a PCR analysis. The glycolytic genes expression (HK, PFK, PK) were highest in YP, whereas expression of genes related to adipogenesis (C/EBPα, FABP4, SCD1) were highest in QYP. As expected, genes associated with angiogenesis and hypoxia (, ) were expressed at the highest levels in TP. The composition and proportion of amino and fatty acids in pig muscles at the three altitudes examined also varied substantially. Among the breeds, TP had the highest proportion of umami amino acids, whereas QYP had the highest proportion of sweet amino acids. However, TP also exhibited the highest proportion of essential fatty acids and the lowest proportion of n6:n3. This study explains the high-altitude adaptive evolution and the formation of meat quality differences in different altitude pigs from various angles and provides a reference for local pork food processing and genetic improvement of local pigs. 10.3390/ani9121080

Comparison of energy metabolism and meat quality among three pig breeds. Animal science journal = Nihon chikusan Gakkaiho The objective of this study was to evaluate the effects of muscle-fibre types and hormones on glycolytic potential and meat quality traits and their association with glycolytic-related gene expression in three different altitude pig breeds. The pig breeds studied were the Tibetan pig (TP, high altitude), the Liang-Shan pig (LSP, middle altitude) and the Duroc×(Landrace×Yorkshire) cross (DLY, flatland). The results indicated that TP and LSP had better meat quality than DLY (P<0.01). The glycolytic potential (GP) increased in the order of TP<LSP<DLY and decreased with time post mortem. DLY had higher glucagon and epinephrine contents than LSP and TP (P<0.01). The proportions of myosin heavy chain muscle fibers type I in the Longissimus dorsi increased in the order of DLY<TP<LSP, whereas the proportion of type IIb increased in the order of TP<LSP<DLY. The expression of gene PKM2 played an important role in the glycolysis rate of the different genotypes. Compared with the other two pig breeds, the high-altitude breeds had better meat quality attributes, which may be due to the slow rate of glycolysis metabolism. 10.1111/asj.12207