Effects of in-the-bag dry-ageing on meat quality, palatability and volatile compounds of low-value beef cuts

Dry-ageing impacts on meat quality, oxidative stability, and release of free amino acids in striploins from dairy crossbred yearling and 2-year-old steers

This study determined the impacts of dry-ageing on meat quality, oxidative stability, and release of free amino acids (FAAs) in striploins from dairy-crossbred yearlings and 2-year-old steers (n = 12 each group) over 21 days of in-bag dry-ageing. Dry-ageing increased weight losses, with higher % drying rates in yearling meat during dry-ageing, likely due to the smaller loin size and lower intramuscular fat content (P < 0.05). Yearling meat showed greater (P < 0.05) decreases in moisture content, but both meats reached similar moisture levels by day 21. pH values increased with dry-ageing with variations at different ageing times. Dry-ageing reduced a*, b*, and chroma while increasing L* and hue angles on day 21 (P < 0.05), likely due to dehydration and lipid oxidation (higher TBARS, P < 0.05) after 14 days, especially in yearling meat. The decreased levels (P < 0.05) of some monounsaturated fatty acids and conjugated linoleic acid cis-9, trans-11 were likely linked with lipid oxidation. Total levels of FAAs and essential amino acids increased significantly, especially within the first 7 days, with distinct patterns between the two meats. Dry-aged yearling meat contained more FAAs associated with sweat taste (e.g., glutamine and glycine) and fewer FAAs associated with bitter taste (e.g., phenylalanine and tyrosine). Carnosine levels varied and significantly increased after 21 days. Dry-ageing demonstrated distinct effects on dehydration, lipid oxidation, and release of FAAs in meat from yearlings compared with 2-year-old steers, which can be tailored to develop high-quality beef products with unique flavours.

Effect of accelerated aging on shelf-stability, product loss, sensory and biochemical characteristics in 2 lower quality beef cuts

The aim of this study was to determine the impact of accelerated aging (AA) on shelf stability, product loss, sensory and biochemical characteristics of 2 lower quality beef cuts. Triceps brachii (TB) and semimembranosus (SM) were collected and fabricated from 10 USDA Choice beef carcasses and assigned to 1 of 6 treatments: 3 d cooler aged (control), 21 d cooler aged, AA 49 °C for 2 h, AA 49 °C for 3 h, AA 54 °C for 2 h, and AA 54 °C for 3 h. The results showed that AA can decrease APC counts on steak surface and in purge and redness, but increase lightness and product loss of the steaks (P < 0.01). Lower shear force was also found for AA steaks compared to those from the control (P < 0.01), with the AA 54 °C treatments being comparable to 21 d cooler aging. However, the trained sensory panel determined AA steaks were less juicy and flavorful than those from the control and 21 d cooler aged samples (P < 0.05). There was no off-flavor detected in AA steaks though lipid oxidation was higher in AA samples than those in the control steaks (P < 0.01). The AA treatments stimulated cathepsin activity (P < 0.05), which may have enhanced the solubilization of stromal proteins and led to a different troponin-T degradation pattern compared to those from the 21 d aged samples (P < 0.01). Although AA is an economical and time-efficient method to increase tenderness of lower-quality beef cuts, further research is needed to determine strategies to mitigate the decrease in juiciness from AA treatments.