title: Post mortem rigor development in the Egyptian goose (Alopochen aegyptiacus) breast muscle (pectoralis): factors which may affect the tenderness.
abstract: BACKGROUND
  Baseline research on the toughness of Egyptian goose meat is required. This study therefore investigates the post mortem pH and temperature decline (15 min-4 h 15 min post mortem) in the pectoralis muscle (breast portion) of this gamebird species. It also explores the enzyme activity of the Ca(2+)-dependent protease (calpain system) and the lysosomal cathepsins during the rigor mortis period.
  
  
  RESULTS
  No differences were found for any of the variables between genders. The pH decline in the pectoralis muscle occurs quite rapidly (c = -0.806; ultimate pH ∼ 5.86) compared with other species and it is speculated that the high rigor temperature (>20 °C) may contribute to the increased toughness. No calpain I was found in Egyptian goose meat and the µ/m-calpain activity remained constant during the rigor period, while a decrease in calpastatin activity was observed. The cathepsin B, B & L and H activity increased over the rigor period.
  
  
  CONCLUSIONS
  Further research into the connective tissue content and myofibrillar breakdown during aging is required in order to know if the proteolytic enzymes do in actual fact contribute to tenderisation.
authors: Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, (Stellenbosch) 7602, South Africa.|Department of Food Science, Stellenbosch University, Private Bag X1, Matieland, (Stellenbosch) 7602, South Africa.
authors: Greta
authors: G
authors: Geldenhuys
authors: Department of Food Science, Stellenbosch University, Private Bag X1, Matieland, (Stellenbosch) 7602, South Africa.
authors: Nina
authors: N
authors: Muller
authors: Animal Production Institute, Agricultural Research Council of South Africa (ARC-API), Private Bag X2, Irene 0062, South Africa.
authors: Lorinda
authors: L
authors: Frylinck
authors: Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, (Stellenbosch) 7602, South Africa.
authors: Louwrens C
authors: LC
authors: Hoffman
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002154:Calpain / Q000378:metabolism*; D002403:Cathepsins / Q000378:metabolism*; D004534:Egypt; D005260:Female; D005777:Geese; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000032:analysis*; D010369:Pectoralis Muscles / Q000378:metabolism*; D012298:Rigor Mortis; D013314:Stress, Mechanical; D013696:Temperature
chemical_list: D002135:Calcium-Binding Proteins; C033668:calpastatin; D002403:Cathepsins; D002154:Calpain; C449000:m-calpain
keywords: Egyptian geese; calpains; cathepsins; gamebirds; pH; rigor mortis