Comparison of proteolysis in native, heat-treated and aged proteins from turkey meat.
1. The present study compared the ability of native, heat-treated and aged turkey breast muscle proteins to undergo proteolysis by digestive tract proteases. 2. Domestic turkey toms were slaughtered under laboratory conditions. Breast muscles were excised immediately post mortem; one was placed under conditions to develop exudative meat by maintaining the muscle at 40 degrees C for at least 30 min and the other was refrigerated under commercial conditions. 3. Meat was collected and stored for 7 d at 4 degrees C. Breast samples removed at d 0 and d 7 were frozen and stored at -80 degrees C until used for determination of solubility, protein surface hydrophobicity and protein oxidation through carbonyl content. Measurements of pepsin and trypsin/chymotrypsin activities were performed in vitro on myofibrillar proteins. 4. Storage increased carbonyl content in control samples while the oxidation increase was not significant in heat-treated myofibrillar protein. Hydrophobicity was not affected by storage time or treatment or protein solubility. 5. Storage significantly increased trypsin + chymotrypsin activity only in the control group. The activities of pepsin and trypsin + chymotrypsin were negatively correlated with protein surface hydrophobicity.
Santé-Lhoutellier
V S
VS
INRA, UR QuaPA370, Saint Genès Champanelle, France. veronique.sante@clermont.inra.fr
Théron
L
L
Cepeda
M
M
Grajales
A
A
Gatellier
P
P
D000375:Aging; D000818:Animals; D002918:Chymotrypsin / Q000032:analysis; D003296:Cooking; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D006920:Hygiene; D008460:Meat / Q000032:analysis* / Q000592:standards; D018482:Muscle, Skeletal / Q000737:chemistry; D011180:Postmortem Changes; D011506:Proteins / Q000032:analysis*; D012995:Solubility; D014357:Trypsin / Q000032:analysis; D014422:Turkeys
D011506:Proteins; D002918:Chymotrypsin; D014357:Trypsin