INCREASING THE EFFICIENCY OF POULTRY AND FISH FREEZING USING PROTECTIVE PECTIN COATINGS

Abstract

Maintaining the quality of poultry and pond fish as much as possible is important. Freezing poultry immediately after slaughter and fish after catching allows you to solve this problem. Freezing in liquid media leads to an increase in the speed of the process and, accordingly, a better preservation of the quality indicators of products. At the same time, in the process of freezing in brines containing calcium chloride, it leads to the diffusion of calcium ions into the muscle tissue of poultry or fish and the appearance of a bitter taste. To prevent salting out of raw materials, we have proposed the use of biologically inert coatings based on pectin. The purpose of this study is to study the possibility of using low methoxylated pectin substances to improve product quality. The influence of a number of technological factors on the protective properties of the coating is studied. These factors include the concentration of pectin substances, the pH of the medium, the presence or absence of pretreatment of the surface of a poultry or fish carcass with citric acid. The strength of the coating and its barrier properties with respect to the diffusion of calcium ions have been studied. It is recommended to use a concentration of pectin substances of 3% with preliminary treatment of the carcass surface with 1% citric acid solution, followed by fixing the formed pectin film with 1% calcium chloride solution. Such processing allows to achieve a maximum concentration of calcium chloride in the muscle tissue of poultry or fish of no more than 0.5% – the value allowed by the standard. It is shown that the use of freezing in brine leads to a significant decrease in the weight loss of the product during storage compared to freezing in air – three times. The use of a coating based on pectin can reduce weight loss by a factor of eight. The quality indicators of products are also much better preserved – water retention capacity, acid number of fat and peroxide value of fat. The organoleptic properties of poultry and fish processed according to the proposed technology are noticeably superior to those of raw materials frozen both in air and in brine without applying a protective coating.