Changes in physicochemical quality and protein properties of porcine longissimus lumborum during dry ageing

Abstract

The present study investigated the effects of dry-ageing time on physicochemical quality and protein properties of porcine longissimus lumborum within 48 h of postmortem ageing. Results showed that appropriately prolonged dry-ageing time (24 and 36 h) had a positive effect on the tenderness, water-holding capacity, thermal stability and gel properties of meat, as evident from the decrease of shear force, dripping loss, cooking loss, T 2 relaxation time, enthalpy value and the increase in storage and loss modulus. Nevertheless, the excessive extension of ageing (48 h) increased the degree of protein oxidation and degradation by maintaining the lowest total sulfhydryl but the highest carbonyl content, and producing more small molecular weight protein chains (35.4, 20 and 19.6 KDa). Chemometric analysis further clarified the appropriate ageing time of desirable meat. In conclusion, dry ageing 24 and 36 h were suggested as the reasonable postmortem ageing time for porcine longissimus lumborum in China.

Analysis of Quality after Sous Vide of Pork Loin Wet-Aged using Pulsed Electric Field System

“…The CIE b* in the PEFR group (0°C and –1°C) after 3 weeks of aging was higher than that after 2 weeks of aging, showing that an increase in the aging period increases the CIE b* of sous vide pork loin. Wang et al (2022) reported that as the aging period increases, oxidation of muscle also increases, leading to more CIE b*. Chroma was significantly higher in the raw meat samples than in the wet-aged group (p<0.05) and higher in the PEFR group than in the CR samples (p<0.05).…”

A solution for fillet quality: Slaughter age's effect on protein mechanism and oxidation

“…Regarding muscle type, there are reports that the light scattering properties of some muscles are increased by postmortem protein degradation, which promotes an increase in the L* value [ 30 ]. Colored components are often formed by protein oxidation and degradation, and a high degree of protein oxidation and degradation causes meat discoloration during aging [ 37 , 38 ]. In our study, a* value was found to be higher in group B.…”

“…During aging, it is reduced to myoglobin by metmyoglobin reductase. However, metmyoglobin reductase activity gradually decreases with aging and the flesh color can change from red to brown [ 37 , 38 ].…”

“…It has been reported that higher pH of muscle has favorable effects for fillet tissue index, including firmness, chewiness, and springiness [ 40 ]. Other studies revealed that muscle fiber condition can have a significant positive correlation with fish stiffness [ 37 , 38 ]. Due to textural and structural changes in the postmortem period, the distribution and mobility of water in myofibrils may undergo changes.…”

“…The presented results show that T max 2 for group A and B fillets increased by 72 % and 58.5 %, respectively, compared with MPs by slaughter age. This increase may be due to irreversible cross-bridge formation between myosin and actin [ 37 , 38 ]. In accordance with the previously presented results regarding the thermal stability of miyofibrillar protein, the energy required for the proteins denaturation gradually increased in an age-related manner, and then decreased at a similar rate.…”