Research of ostrich fat properties when melting in electrochemically activated medium

Abstract

In recent decades, there has been a growing scientific interest in various kinds of technologies using electro-activated solutions with high reactivity and representing a powerful toolkit for intensification of production processes. However, theoretical knowledge about the regularities of change in fat properties during melting in an electrolyte is rather fragmentary, scarce and often contradictory. The work is devoted to the study of the main factors influencing the change in physical and chemical properties and yield of fat in the process of melting using catholyte, to substantiate the feasibility of its use and develop an industrial line for obtaining fat. The object of studies was ostrich fat obtained by traditional method – by melting in water and by experimental technology – in catholyte as well as technological regimes of fat extraction. According to the data obtained, the fat melted at pH of catholyte 11, temperature 100 and 75 °С was characterized by low values of acid number – 0,45 mg KOH/g and 0,40 mg KOH/g, respectively. The opposite trend was observed with a successive decrease in the alkalinity of the ECA medium and an increase in the melting temperature of the fat, which led to an increase in the content of secondary oxidation products in the experimental samples. It was found that due to the high reactivity of the EСA medium, the temperature and pH of the catholyte increased, the intermolecular interaction within the fat phase decreased, which increased the mobility of lipid molecules relative to each other. The lowest values of fat viscosity (0,42 and 0,4 kPa?s) were recorded when treating fatty raw materials in catholyte with pH 10.5 and 11 and temperature 100 °С. It is shown that increasing the pH of the catholyte contributes to minimizing the values of peroxide number of ostrich fat, in contrast to the heating temperature. It is established that processing of raw materials in catholyte at 75 °C resulted in the yield of fat 88,4–90,1%, which is almost 1,4 times higher than when melted in water. In the wet method of mellowing in water, denaturation of protein structures and a higher degree of fat extraction can be achieved at a mellowing temperature above 75 °C, in contrast to the proposed method of processing raw materials.