Time filter

Source Type

Jose C.G.,Australian Sheep Industry CRC | Jacob R.H.,Australian Sheep Industry CRC | Gardner G.E.,Australian Sheep Industry CRC | Pethick D.W.,Australian Sheep Industry CRC | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

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. © 2010 American Chemical Society. Source

Jose C.G.,Australian Sheep Industry CRC | Jose C.G.,Murdoch University | Jacob R.H.,Australian Sheep Industry CRC | Pethick D.W.,Australian Sheep Industry CRC | And 3 more authors.
Meat Science | Year: 2016

The relationship between vitamin E supplementation rate and colour stability was investigated using 70 mixed sex 6-8 month old crossbred lambs. An initial group of 10 were slaughtered, while the remainder were fed a pellet ration containing either 30, 150, 275 or 400IU vitamin E/kg ration or on green pasture for 56days. After slaughter, carcases were halved; one side packed fresh (5days) and the other in CO2 (21days), both at 2°C. Five muscles were set for retail display for 96h. The oxy/metmyoglobin ratio was measured every 12h. Colour stability increased with increasing muscle vitamin E until an apparent maximum effect for vitamin E concentration (3.5-4.0mg α-tocopherol/kg tissue) was reached beyond which no further response was evident. This was reached within 3-4weeks (275IU treatment), and meat from these lambs should reach 60h retail display with a satisfactory surface colour. This effect was most apparent in aerobic muscle types and meat aged post slaughter. © 2015 Elsevier Ltd. Source

Discover hidden collaborations