Seasonal variation in red deer (Cervus elaphus) venison (M. longissimus dorsi) drip loss, calpain activity, colour and tenderness.
Sixty four young red deer (Cervus elaphus) stags (<2 years old) were slaughtered at four different times (December (Group 1); n=17, March (Group 2); n=8, July (Group 3); n=20 and September (Group 4); n=19) to evaluate seasonal effects on venison quality. M. longissimus dorsi samples for calpain analysis were collected on the slaughter line and the rest of these muscles were collected at 1 day post-slaughter. Loins were divided into four parts and randomly allocated to storage for 1 day, 3, 9 or 14weeks at -1.5°C and then vacuum packaged. Seasonal variation was demonstrated in venison pH. Highly significant positive regressions were found for shear force (P<0.001) and colour display life (P<0.001) on pH, where higher pH values were associated with tougher venison and longer colour display life. A clear trend of increasing fluid loss during storage, calculated as amount of purge at 14 weeks of storage minus the amount of drip loss at 1 day post-slaughter, was evident, averaging 2.5% (SEM 0.17) over the four groups. The relative activities of the calpastatin-bound calpain, μ-calpain and m-calpain all exhibited a seasonal pattern although there was no evidence (P>0.05) that this affected tenderness. There was a highly significant (P<0.001) negative regression for the average over the four storage times of drip and purge on calpastatin-bound calpain activity.
Wiklund
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AgResearch Limited, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand. eva@sapmi.se
Dobbie
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Stuart
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Littlejohn
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RP
D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002154:Calpain / Q000378:metabolism*; D003116:Color; D003670:Deer; D005524:Food Technology; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000032:analysis; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D012621:Seasons; D013314:Stress, Mechanical; D014867:Water
D002135:Calcium-Binding Proteins; D009124:Muscle Proteins; D014867:Water; C033668:calpastatin; D002154:Calpain