Studies on Control of the Denaturation of the Fish Muscle Proteins during the Frozen Storage-I

Abstract

For the further improvement of the frozen storage of meat and fish meat, deeper know ledge of the mechanism of the freezing denaturation of the muscle proteins as well as better techniques controlling the denaturation are needed. With respect to the denaturation mechanism, various theories or hypotheses have been presented so far, attributing its main cause to the aggregation of the protein molecules1), either through the removal of water2,3), or through the salting-out of the proteins4), to the poisonous effect of the free fatty acids5), to the pH change6), to the formation of formaldehyde7), etc., but the com plicated process of the denaturation brings about difficulties in studying the methods of its control.With a view to obtain information on the denaturation mechanism through the in teraction of the proteins with other substances, as well as to find out some new materials to prevent the denaturation, the authors have been testing the denaturation of a frozen actomyosin preparation of the carp at the presence of a variety of additives, and have found out a preventive effect of monosodium-glutamate (Na-glutamate).The present paper deals with the in vitro model tests for the effect of Na-glutamate on the isolated actomyosin preparation and also with the study on the quality of the "Kamaboko" jelly which is processed from the minced fish meat frozen -stored with and without added Na-glutamate. The latter experiment was performed to check the appli cability of adding Na-glutamate to the Reitosurimi (frozen minced fish meat). Recently, the Reitosurimi became the major material in the Kamaboko manufacture. Moreover, it was aimed that the results with the jelly forming ability as revealed in the quality of Kamaboko could make an information of the wider applicability of this method to the control of the frozen storge denaturation of other foods such as meats and meat products, because the jelly-forming ability of a material is a good index of the state of the actomyosin molecules which makes the major factor of the texture of meats.The tests in 0.05M KCl make a model for the frozen storage of the meat and the

Suppression of thermal denaturation of myosin and salt-induced denaturation of actin by sodium citrate in carp (Cyprinus carpio)

“…However, addition of sugars to surimi gives sweetness although using sorbitol instead of sucrose reduces the sweetness. It is also reported that the other compounds, such as sodium (Na-) glutamate or Na-acetate suppress myosin denaturation (Noguchi & Matsumoto, 1970;Ooizumi, Yamamura & Arai, 1982;Ooizumi, Nara & Arai, 1984;Matsuura, Ooizumi & Arai, 1984). Strong taste of Na-glutamate and weak suppressive effect of Na-acetate are their demerit.…”

EFFECT OF FROZEN STORAGE AND CRYOPROTECTANTS ON FUNCTIONAL PROPERTIES OF TILAPIA (Oreochromis mossambicus) FISH.

“…Where;  red = reduced viscosity (ml/mg) t 1 = flow time for protein solution (sec) t 0 = flow time for solvent, EB (sec) C = concentration of protein in the solution (mg/ml) Changes in calcium ATPase activity:-Calcium ATPase activity was measured by using spectro-photometric method (Noguchi and Matsumoto, 1970). About 1 g of meat was homogenized in 10 ml of 0.05M Tris-HCL buffer, pH 8.0.…”

The change of thermal gelation properties of horse mackerel mince led by protein denaturation occurring in frozen storage and consequential air floatation wash

“…The protein extracts, water-soluble proteins (WSP) and myofibrillar proteins (MP) were prepared according to the method of Noguchi (1974). Protein concentration was determined by the method of Bradford (1976) using bovine serum albumin (BSA) as the standard.…”