Histological, Physicochemical And Microbiological Changes In The Carp (Cyprinus Carpio) Muscles After Freezing

The objective of the study was to determine the effect of freezing at -18 degrees C on the histological structure and some physicochemical and microbiological indicators of carp (Cyprinus carpio) dorsal and abdominal muscles. The muscles showed damage after freezing once and twice, but they were more significantly deformed and destructured after double freezing. Water content, crude protein, and fat showed no significant differences between fresh carp and carp frozen once and twice. Water activity of the abdominal and dorsal muscles showed significant differences (p < 0.001) after freezing. Significant differences (p < 0.05) were also found in the ash content of the abdominal and dorsal muscles after freezing. The total number of microorganisms and Enterobacteriaceae did not show significant differences (p > 0.05) between fresh carp and carp frozen once and twice. The histological study showed clear morphological differences between muscle fibers of fresh carp (Cyprinus carpio) and carp frozen once and twice. Muscles are damaged to a greater extent after double freezing. Freezing affected water activity and ash content. The microbiological indicators of carp do not change significantly after storage for 30 days in a frozen state.