Decrease in Intramuscular Levels of Phosphatidylethanolamine Bearing Arachidonic Acid During Postmortem Aging Depends on Meat Cuts and Breed

Abstract

The intramuscular phospholipid (PL) level is reported to decrease upon postmortem aging of beef, pork, and chicken, and the change affects meat qualities (e.g., myofibrillar fragmentation and drip loss); however, there is still little information on the effect of muscle position and breed on PL compositions. A preliminary study is performed to investigate the effect of intramuscular PL composition on postmortem aging of beef and venison. Loin and round parts of beef and venison are kept at 4 °C for 28 postmortem days to elucidate the maximum effect of meat aging. The arachidonic acid (20:4n‐6) content in PL decreases in round meat during postmortem aging, while the PL 20:4n‐6 content is not affected in loin meat. The PL molecular species analysis reveals that such content reduction is consistent with decreases in phosphatidylethanolamine (PtdEtn) levels, especially that bearing 20:4n‐6. In addition, the content reduction by aging is affected by the meat cuts and the breed. These results suggest that PL variation depends on meat cuts and breed, and the release of 20:4n‐6 from PL has a considerable influence on meat qualities owing to the high reactivity of the polyunsaturated chain. The present results will enable eventual improvement of the taste, smell, and texture of meat during postmortem aging. Practical Applications: This preliminary study investigates the changes in intramuscular PL composition in beef and venison after postmortem aging. Consequently, PL variation depends on meat cuts and may be induced potentially owing to activity of cytosolic phospholipase A2. Meat properties (e.g., drip, flavor, and taste) are considered as affected by the PL hydrolysis and the 20:4n‐6 release. Therefore, monitoring of variation of PL species might be useful to estimate the condition of meat quality by postmortem aging. Our preliminary study investigates the changes in intramuscular phospholipid (PL) composition in beef and venison after postmortem aging. Postmortem aging decreases the phospholipid levels in meats. The 20:4n‐6 is released from the meat phospholipid during postmortem aging. The two above‐mentioned are considered due to hydrolyzation of the diacylglycerophospholipids in meats. The hydrolysis of phospholipid may depend on meat cuts and breed.

Dietary PlsEtn Ameliorates Colon Mucosa Inflammatory Stress and ACF in DMH‐Induced Colon Carcinogenesis Mice: Protective Role of Vinyl Ether Linkage

“…DMH is metabolically activated into the highly reactive methyl diazonium ion in the liver and is either transported into the colon through excretion into the bile or directly from blood circulation (Fiala and Stathopoulos, 1984). Intraperitoneal administration of DMH has been shown to induce inflammatory and oxidative stress as well as ACF formation (Moulahoum et al, 2018; Yamashita et al, 2019). Colon cancer can be induced by dedifferentiation‐associated epigenetic regulations by chronic inflammation (Bartsch and Nair, 2006).…”

“…Phospholipid species were analyzed using liquid chromatography–tandem mass spectrometry (LC–MS/MS) operated in the multiple reaction monitoring (MRM) mode. Fatty acid methyl esters (FAME) and dimethyl acetals (DMA) were prepared from lipid extracts and analyzed by gas chromatography (Yamashita et al, 2019).…”

“…Total cholesterol in liver homogenates (n = 8) was determined using a total cholesterol kit (T‐Cho E) (FUJIFILM Wako Shibayagi Corp.). Total lipid content in the colon mucosa and liver were calculated based on fatty acid profiles by conversion into triacylglycerols (Yamashita et al, 2019). The protein levels of the samples were measured using the DC Protein Assay kit (Bio‐Rad, Hercules, CA, USA).…”

Sphingolipid Properties in Sake Rice Cultivars and Changes During Polishing and Brewing

“…The sphingolipids were quantified based on the ratio difference as added IS amount. In terms of fatty acid analysis, without extraction, the composition in sake was determined by GC-MS after direct ethylation using heptadecanate as IS and those in other samples were by direct methylation 25 . Briefly, sample with or without IS was reacted in ethanol or methanol containing acetyl chloride at 100 .…”

Sake (Rice Wine) Brewing Hydrolyzes Highly Polar Sphingolipids to Ceramides and Increases Free Sphingoid Bases

“…The GC-MS system was equipped with a GC-2030 and GC-MS-QP2020NX instrument Shimadzu, Kyoto, Japan . For fatty acid analysis, the samples of koji rice and sake yeast were directly methylated and determined using GC-MS 26 . For analysis of the sake yeast sphingolipids, the fractions were treated with trimethylsilylation TMS and analyzed using GC-MS 27 .…”