Chemical evaluation of some fresh and frozen fish

Abstract EN

The aim of this study was to evaluate meat and meat products chemically.

About 25 samples of fresh meat, 25 samples of frozen meat and 25 samples of frozen minced meat were collected from different markets in Mansoura City.

All these samples were chemically examined.

Data analysis revealed an increase of pH in frozen meat and frozen minced meat with the means 6.4 and 6.3 respectively, while the pH was normal in fresh meat with the mean 5.8.

In respect to total volatile basic nitrogen (TVB-N) and thiobarbituric acid (TBA), they were in normal levels in fresh meat with the means 12.5 and 0.275 respectively.

While in frozen meat and frozen minced meat their values increased with the means 21.6and 0.713, 20.5 and 0.664 respectively.

Regarding heavy metals concentration the mean values of lead, cadmium and mercury in fresh meat were 0.067, 0.046 and 0.008 ppm respectively.

In frozen meat the means were 0.045, 0.035 and 0.006 ppm respectively, while in frozen minced meat were 0.032, 0.025 and 0.004 ppm respectively.

Concerning marathon residues in fresh meat, frozen meat and frozen minced meat the mean values were 0.07, 0.05 and 0.03 respectively, while diamethoate residues were with the means 0.02and 0.03 in fresh and frozen meats respectively and not be detected in frozen minced meat.

It can be concluded that meat and meat products are able to be exposed to chemical changes, in addition to presence of some pollutants residues, these changes may lead to spoilage of meat and may constitute public health hazards, so meat and meat products in markets must be examined frequently.