Thermally induced changes in protein extractability of postrigor turkey breast meat measured by two methods

Extractability of sarcoplasmic and myofibrillar proteins was reduced in pos trigor turkey breast meat held at 40 degrees C for as short as 30 min. Thes e reductions in protein extractability were successfully detected, using ei ther a filtration-based methodology or one based on centrifugation, However , the coefficient of variation for the filtration method was as much as 4 t imes greater than for centrifugation. Additionally, the filtration method o verestimated sarcoplasmic protein extractability due to the inability to ex clude myofibrillar proteins. Centrifugation results indicated the extractab ility of proteins in 0.55 M KCI was reduced to 52% of controls for samples held at 40 degrees C for 120 min. Additionally, holding postrigor turkey br east muscle at 40 degrees C resulted in increased myosin degradation.