title: The effect of ultra-rapid chilling and subsequent ageing on the calpain/calpastatin system and myofibrillar degradation in lamb M. longissimus thoracis et lumborum.
abstract: The effect of ultra-rapid chilling (-20°C) on the proteolytic degradation of myofibrillar proteins during ageing, by the calpain/calpastatin system in lamb was investigated. Carcasses (36) were ultra-rapidly chilled (-20°C for 3.5 h followed by 20.5 h at +4°C) or chilling at +4°C for 24 h. After chilling all carcasses were stored at +4°C for a further 4 days. Samples of M. longissimus thoracis et lumborum were taken for Warner-Bratzler shear force measurement, sarcomere length, SDS-PAGE and enzyme activity analysis. Ultra-rapid chilling (-20°C) had no effect on the proteolytic degradation of myofibrillar proteins by the calpain/calpastatin system compared to conventional chilling (+4°C). However, no difference in tenderness was found between the two chilling regimes at 1 or 5 days postmortem so differences in myofibrillar degradation or enzyme activity would not be expected.
authors: The National Food Centre, Teagasc, Dunsinea, Castleknock, Dublin 15, Ireland.
authors: G A
authors: GA
authors: Redmond
authors: B
authors: B
authors: McGeehin
authors: J J
authors: JJ
authors: Sheridan
authors: F
authors: F
authors: Butler