MSA Sheep Meat Eating Quality PDF

tips & tools MSAS4 MEAT STANDARDS AUSTRALIA The effect of breed and age on sheepmeat eating quality The effect of breed on eating quality Research shows sheepmeat eating quality is not greatly Key points affected by breed. Due to the his...

tips & tools MSAS4 MEAT STANDARDS AUSTRALIA The effect of breed and age on sheepmeat eating quality The effect of breed on eating quality Research shows sheepmeat eating quality is not greatly Key points affected by breed. Due to the historical success of the wool Sheepmeat eating quality is not greatly affected by industry, around 70% of Australian sheep genetics are Merino. breed. Other breeds are increasingly promoted for meat production because they generally have better growth rates, better An increase in the proportion of Merino genes increases reproductive performance and more heavily muscled an animals sensitivity to stress prior to slaughter. carcases which are better suited to meat production. Research has shown that processing regimes can The key factors to optimised eating quality from all breeds is improve eating quality and consistency of all classes of good nutrition and stress minimisation prior to slaughter. sheepmeat. It should be recognised that while the eating quality of Merino Lamb  has the best sheepmeat eating quality when lamb and sheepmeat can be as good as other breeds, they comparing like-for-like (eg same cuts, same processing do require more careful pre-slaughter management than other method, same cooking method). breeds, with key factors being good nutrition and stress minimisation prior to slaughter. Mutton loin can have a similar eating quality to hogget loin. The Merino breed has an increased sensitivity to stress, which also extends to Merino crosses. This is further explained in figure 1 where the loss of muscle glycogen between farm and Figure 1: Loss of muscle glycogen between farm and slaughter post-slaughter is compared between two cuts for three for Merinos and crossbreeds. genotypes handled under identical conditions. Merinos lost more glycogen than crossbred lambs, with the first cross 0.7 being affected proportionately, which subsequently resulted in 0.6 Glycogen loss (g/100g muscle) Topside higher pH meat. In low-stress pre-slaughter conditions, Merino Eye round lambs can perform as well as crossbreds with no differences 0.5 in glycogen, meat colour or pH. 0.4 Provided that nutrition is adequate and animals are finished to 0.3 a minimum fat score of 2, the intramuscular fat concentration of Merinos is either the same or higher than that of other 0.2 breeds. 0.1 There is also some evidence that some genes for increased muscling may lead to a significant reduction in eating quality 0 Merino First-cross Second-cross through reduced tenderness. More information on the requirements for reducing stress when handling sheep can be Source: Improving lamb and sheepmeat eating quality – found in other components of MSA Tips & Tools. a technical guide, 2006. 7  The effect of animal age on eating quality Research found that lamb remains the premium product and has the best sheepmeat eating quality when comparing like- The eating quality differences between lamb, hogget and for-like (eg same cuts, same processing methods). Some cuts mutton are based on: of hogget and mutton also show potential for high eating quality. the toughening of connective tissue Figure 3: Change in eating quality attributes with sheep age. adverse flavours accumulating in fat as a result of age 70 the darkening of meat colour with age. Connective tissue is visible as sinew, ‘silverskin’ and ‘gristle’ within meat. As the animal ages, this invisibly permeates (0 = very poor, 100 = excellent) 60 Flavour muscle. In older animals, ‘tougher’ connective tissues do not Overall liking score melt as easily with cooking, so are more easily detected as Tenderness the ‘background toughness’ in meat. This effect is shown in figures 2 and 3, which summarises data 50 Juiciness from large numbers of Australian consumers who tested grilled cuts from lamb and mutton. Better cuts of meat, like eye of loin, have less connective tissue but these also 40 become tougher as sheep get older. 0 20 40 60 80 Sheep age (months) Hogget loin cuts, when processed under optimal conditions, have only slightly lower eating quality than lamb loins. Source: Improving lamb and sheepmeat eating quality – a technical guide, 2006. Figure 2: ‘Overall liking’ of eating quality of five grilled cuts from lamb and mutton. 70 Lamb Mutton 60 (0 = very poor, 100 = excellent) 50 Overall liking score 40 30 For more information 20 Visit www.mla.com.au/msa or contact MSA 1800 111 672. 10 0 Loin Rump Outside Topside Round Source: Improving lamb and sheepmeat eating quality – a technical guide, 2006. Note: Optimal processing used: electrical stimulation + 5 days ageing; no stimulation + 10 days ageing; or tenderstretch + 5 Level 1, 40 Mount Street days ageing. North Sydney NSW 2059 Ph: +61 2 9463 9333 Fax: +61 2 9463 9393 www.mla.com.au Released: July 2019 MLA makes no representation as to the accuracy of any information or advice contained in this document and excludes all ISBN: 1 74036 391 4 liability, whether in contract, tort (including negligence or breach of statutory duty) or otherwise as a result of reliance by any © Meat & Livestock Australia person on such information or advice. ABN 39 081 678 364 8