Ribose-Induced Maillard Reaction as a Quality Index in Frozen Minced Chicken and Pork Meats

摘要

Minced meats underwent denaturation, oxidation and aggregation during frozen storage, causing decrease in denaturation enthalpy, sulfhydryl contents and protein solubility, as well as increase in protein carbonyl and disulfide contents. These changes were more evident in samples stored at −4C than those stored at −20C, as reactions occurred at faster rates at higher temperature. The addition of ribose on thawed minced meats followed by heating at 95C initiated Maillard reaction browning. Browning index () was significantly higher (P < 0.05) in fresh minced meats than in frozen ones, decreased with storage time and were lower in minced meat stored at −4C than those stored at −20C. The biochemical changes in meat proteins during frozen storage reduced the availability of basic amino acids to take part in the Maillard reaction. Hence, could be used as freshness index in minced chicken and minced pork.Practical ApplicationsLong-term frozen storage of meat causes degradative changes which leads to the loss of functionality, flavor, texture and organoleptic properties of the meat. Due to these losses, fresh meat is often perceived to be of a better quality and often valued at a higher market price compared to those of frozen meat. This study proposed an alternative, simpler, quicker and cheaper method to identify between fresh versus frozen/thawed meat. The proposed method was based on the Maillard reaction between proteins of meat and ribose, yielding brown pigments (melanoidins) that can be measured as absorbance and converted into a freshness index. It was demonstrated that the biochemical degradation during frozen storage reduces the availability of meat proteins to react with ribose, yielding lower freshness index as compared to those of fresh meat. Thus, freshness index could be used as a quality control method to ascertain meat freshness and to evaluate supplier's reliability.