Radiation-Inactivation of Meat Proteases as Determined by a C-14-Labeled Hemoglobin Method.

摘要

It was desired to study the effect of irradiation temperatures and dose on meat enzymes in fresh beef, pork, and chicken muscles. This was done using a rapid method for analysis which utilized a bovine hemoglobin substrate labeled with radioactive K14CNO. The enzyme preparation was incubated with the carbon-14 labeling substrate for 24 hours at 37 C. The amount of radioactivity recovered in the trichloracetic acid-soluble fraction after precipitation of the protein was used to measure the quantity of residual proteolytic enzymes (proteases). The sensitivity of the analyses was greatly improved by the substitution of 1,4-dioxane in place of toluene as the diluent in the liquid scintillation of the precipitated proteins. Samples of raw beef, pork, and chicken muscles were gamma-irradiated at doses of 2, 4, 6 and 8 Megarads and at irradiation temperatures of +21, 0, -30 and -80 C. The results showed a significant effect of both irradiation dose and temperature on the proteases. Irradiation with 2 Megarads at -80 C resulted in no reduction of proteolytic enzymes in beef, a 13% reduction in chicken, and a 13% reduction in pork. Irradiation with 8 megarads at +21 C results in a 86-91% reduction of proteolytic enzymes in the three muscles.