title: Interaction of diet and long ageing period on lipid oxidation and colour stability of lamb meat.
abstract: Eighty-four crossbred wether and ewe lambs were allocated to four finishing diets. The diets were: Lucerne pasture (n=24), Annual ryegrass with sub clover pasture (n=18), Standard commercial feedlot pellets (n=24) and Annual ryegrass based pasture and commercial feedlot pellets (500g/day/head) (n=18). After 8weeks of feeding the lambs were slaughtered and the m. longissimus (LL) and m. semimembranosus (SM) were vacuum packaged and held chilled for 5 (fresh) or 60 (long aged) days, after which samples of each were displayed for 4days under simulated retail conditions. Irrespective of muscle type the long aged samples exhibited a rapid reduction in redness (a*-values) and R630/580nm ratio values such that consumer acceptable thresholds for both traits were quickly exceeded providing limited shelf life. Long ageing also lead to high TBARS levels measured as MDA mg/kg muscle suggestive of a product likely to exhibit rancidity and off flavours from lipid oxidation.
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia. Electronic address: eric.ponnampalam@ecodev.vic.gov.au.
authors.forename: Eric N
authors.initials: EN
authors.lastname: Ponnampalam
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia.
authors.forename: Tim
authors.initials: T
authors.lastname: Plozza
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia.
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Kerr
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia.
authors.forename: Nick
authors.initials: N
authors.lastname: Linden
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia.
authors.forename: Meredith
authors.initials: M
authors.lastname: Mitchell
authors.affiliation: Department of Food Science, University of Otago, PO Box 56, Dunedin, New Zealand.
authors.forename: Alaa El-Din A
authors.initials: AEA
authors.lastname: Bekhit
authors.affiliation: Agriculture Research, Agriculture Victoria, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria 3001, Australia.
authors.forename: Joe L
authors.initials: JL
authors.lastname: Jacobs
authors.affiliation: NSW Department of Primary Industries, Centre for Red Meat and Sheep Development, PO Box 129, Cowra NSW 2794, Australia.
authors.forename: David L
authors.initials: DL
authors.lastname: Hopkins
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D003116:Color; D004032:Diet / Q000662:veterinary; D061353:Food Storage / Q000379:methods*; D018482:Muscle, Skeletal / Q000737:chemistry; D010084:Oxidation-Reduction; D000069466:Red Meat / Q000592:standards*; D012756:Sheep; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D017392:Thiobarbituric Acid Reactive Substances
keywords: Ageing of meat; Colour stability; Fatty acids; Lamb; Lipid stability; Meat quality