Packaging and pH Effects on Meat Discoloration through Electrochemistry

Abstract

Myoglobin is the sarcoplasmic heme protein that determines the color of the meat. The oxidation state of myoglobin results in different forms of myoglobin, such as deoxy-, oxy-, and metmyoglobin. As the deviation from the bright red color of beef affects consumers' purchase decisions, meat packaging is done to retain the meat color and delay spoilage. In these studies, UV-spectrophotometric analysis is combined with the electrochemical method. Meat packaged under different conditions was considered. Two packaging conditions, vacuum and polyvinyl chloride, were compared with the normal unpackaged sarcoplasmic beef sample. Electrochemical regions of both positive and negative potential were diagnosed for sensory peaks where the data of vacuum packaging implied more color stability. To assess the effect of pH on meat discoloration, pH conditions of the physiological state (pH 7.4) and post-mortem meat (pH 5.6) were mainly considered. The rate of meat discoloration was higher at pH 5.6 than at pH 7.4. Electrochemical insights with regard to various packaging effects on meat discoloration will be discussed further.