Conjugated Linoleic Acid and Cholesterol Oxidative Products Generated in Hot Boned Beef Semimembranosus Muscle as Affected by Rigor Temperature, Ageing and Display Time

Abstract

The present study investigated the effect of processing parameters comprising rigor temperature, ageing and display time on conjugated linoleic acid (CLA) concentrations, stability and the development of cholesterol oxidation products in hot boned beef semimembranosus muscles. Meat samples, having attained rigor mortis at 5 °C and 25 °C, were vacuum packed and aged for 7 and 14 days and then displayed under aerobic conditions for 7 days at 4 °C. Lipid was extracted at each time interval then 1H NMR and GC-FID were used for CLA quantification. The cholesterol oxidation products (COPs) were separated from lipids via column chromatography and derivatized for GC-FID. The CLA content was not affected by the rigor temperature, ageing and display time (p > 0.05). The cholesterol oxidative stability was not affected by rigor temperature (p > 0.05) but was affected by ageing and display time (p < 0.05). The COPs, 7α- and 7β-hydroxycholesterol, and 7-ketocholesterol were positively identified and their quantities increased with ageing and display time (p < 0.05). These results demonstrate that the production of COPs in semimembranosus muscle was significantly altered by the ageing and display time parameters but not by the rigor temperature used in this study.

Slaughter Results, Meat Chemical Composition and pH of Aberdinangus, Hereford and Limousin bulls

“…In the studies of other scientists, the dry matter content of M. longissimus muscle ranged from 20.52 to 26.84%, total fat content from 1.10 to 4.42%, protein content from 21.47 to 22.45, ash content from 1.00 to 1.11%, iron content from 14.2 -1 to 22.03 mg kg and cholesterol content from 50.86 to 88.00 -1 mg per 100 g (Brugiapaglia, Lussiana, & Destefanis, 2014;De Marchi et al, 2007;Jemeljanovs et al, 2006;Mateescu et al, 2013;Mungure et al, 2020;Nogalski et al, 2018;Somogyi et al, 2015;Wheeler et al, 1987). In our study, a higher dry matter and total fat content was obtained, but an iron content was lower.…”

“…Cholesterol is considered a risk factor for cardiovascular disease and promotes atherosclerotic changes in the body. Studies performed so far have shown that the cholesterol content of meat is mainly influenced by the feeding stuffs used in cattle fattening and that the breed has no significant effect on its changes (Brugiapaglia, Lussiana, & Destefanis, 2014;Mungure et al, 2020;Wheeler et al, 1987).…”