Alternative cutting methods and dry aging reduce the shear force of hot boned beef striploin in Bos indicus cattle.

Hot boning (HB) is an economical processing technique often resulting in poorer meat quality and tenderness. This study tested a method of partial HB, where the short loin section was removed from the hot carcass and chilled, with the striploin remained in the skeletal system. Thirty six yearling Bos indicus steers carcasses were subjected to either low, high or no electrical stimulation and each side allocated to a cutting treatment of HB, partial HB and conventional (Achillies hung). Striploins were divided into 3 and aged for 5, 14 and 28 days. Warner Bratzler Shear force (WBSF) and sarcomere length were tested. Partial HB resulted in greater tenderization without aging compared to HB. However, optimized electrical stimulation was a requirement. Treatment did not influence sarcomere length. The study also tested the impact of Dry aging of HB striploins, which resulted in further increases in tenderness at 28 days of aging compared to wet aged product, reducing WBSF by 9 N.

A supply chain approach to improving the shelf life of lamb meat; vitamin E concentration, electrical stimulation, ageing period and packaging system.

This study investigated the effects of vitamin E, electrical stimulation, aging and packaging system on the colour stability of lamb meat. Eighty crossbred wether lambs, 6-8months old were fed on either vitamin E or control pelleted diet for 31days prior to slaughter. Half of the carcases from each group were electrically stimulated before being split longitudinally into 2. Each side was randomly allocated 1 of the 4 aging periods (5days fresh, 10, 20 and 30days CO2). Muscle samples were set for retail display, after the respective aging period, colour was measured over 96h. Supplementing vitamin E nutritionally is likely to lengthen the shelf life of lamb products aged longer than 10days. Muscle vitamin E concentrations >3.0mg/kg are required to increase the shelf life of lamb cuts aged for up to 30days to 60h. Medium voltage electrical stimulation did not have a detrimental effect on the display life of aged lamb meat.

Selenium supplementation and increased muscle glutathione concentration do not improve the color stability of lamb meat.

In the eyes of the consumer, a red surface color of lamb meat is desirable. This red color is caused by oxymyoglobin; however, under conditions of retail display this pigment slowly oxidizes and turns brown, deterring consumers. The antioxidant activity of both glutathione (GSH) and selenium has been suggested to slow myoglobin oxidation, thus improving color stability. The following experiment was designed to test the hypothesis that high muscle GSH will improve the color stability of lamb meat, and this effect of GSH will be further improved by supplementing animals with selenium. Forty-eight 12-month-old Merino wether lambs were selected from a flock for high (n = 24) or low (n = 24) GSH concentration in whole blood. Each GSH group was then randomly allocated into two selenium treatments (supplemented with or without 2.5 mg of selenium/kg for 8 weeks). The lambs were slaughtered, and samples were taken from m. semimembranosus (SM) and m. longissimus dorsi (LD) to measure muscle GSH, selenium, and vitamin E concentrations. Further samples were taken to measure color stability (as oxy/metmyoglobin ratio, reflectance at 630/580 nm) over 96 h of retail display. There was no effect of muscle GSH concentration or selenium supplementation on oxy/metmyoglobin ratio at 60, 48, or 30 h of retail display, with the only exception being the non-selenium-supplemented SM samples, which actually decreased in ratio as the muscle GSH concentration increased (P < 0.05). There was a poor correlation between blood and muscle GSH, with a correlation coefficient of 0.18 for the SM and 0.026 for the LD. Thus, it is apparent that neither GSH nor selenium improved the color stability of meat from merino lambs.