Source of Odor The fishy smell and odor of pork is the product of excessive protein breakdown. Pork also has a fishy smell under normal circumstances. It is a small molecule and volatile peptide substance that is decomposed by water-soluble protein in the blood. At low temperatures (0-4°C), the protein and fat of pork can be slowly decomposed to produce rich amino acids and lipids, which can form good and acceptable umami substances and aroma substances. If the storage conditions are poor, such as more microorganisms and higher temperatures. In this case, microorganisms and enzymes are more active, and the