PARAMETERS AFFECTING THE LIBERATION OF SKINS FROM DIFFERENT EGYPTIAN FISH SPECIES COMMONLY USED FOR FILLET PROCESSING.

Document Type : Original Article

Author

Food Technology and Dairy Department. National Research Centre. Dokki Cairo.

Abstract

The solubility of skins from different fish species:  Bolti (Talipia) fish, Wakar (Grouper) and Kishr-Bayad (Nile perch) were investigated using the proteolytic enzymes from their viscera.
                It was found that by careful control of the pretreatment solution, fish viscera enzymes and skin substrates concentrations, fish skins from different species are readily to become solubilized. Concentration of 5.0% NacL. 3.0% HcL and 3% Acetic acid in addition to the proper concentration of viscera enzymes were found to be efficient in solubilizing skins from all the studied species. Increasing the level of NacL more than 5% had an adverse effect of the conversion rate of the skins; due to its inhibitory effect on fish viscera enzymes.
                Logestic regression analysis of both the viscera enzymes and skin concentrations were also employed to stimulate the results. From these equations the optimum concentrations of both fish skin substrates and enzyme concentrations to obtain maximum conversions of the fish skins could to predicted.

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