Polyamines as Potential lndexes for Decomposition of Pork, Beef and Chicken

Abstract

A chemical method to evaluate the freshness and decomposition of pork, beef and chicken was developed. The changes in contents of seven amines, tyramine, putrescine (Put), cadaverine (Cad), histamine, agmatine tryptamine and spermidine (Spd), and those in the pH values were examined in these meats during storage at 0°C and 5°C. In pork, Put was not detected or was found only in a trace amount at the acceptable stage and was present at 1.9 to 2.1ppm at the stage of initial decomposition. The pH value of pork was about 6.2 at initial decomposition. In beef, Put increased gradually with storage time and reached 1.1 to 1.3ppm at the stage of initial decomposition. In chicken, Put was detected in small amounts (less than 1ppm) at the acceptable stage, reaching 2.7 to 3.7ppm at the stage of initial decomposition and increasing markedly at the stage of advanced decomposition. The levels of Cad were also related to the degree of decomposition of chicken; Cad was not detected at the acceptable stage and was produced in small amounts at the stage of initial decomposition. Put seemed to be most useful as an index for freshness and decomposition of these three kinds of meats. The pH values in pork and Cad in chicken were of value as supplementary indexes. Spd was considered to be distributed in the live muscle of these livestocks.