Effect of storage temperature on the change of microbiological indicators of fresh soft cheese

Abstract

In Ukraine, there is a tendency to increase the production of soft, fresh cheeses due to their technological features. The advantages of producing this product include efficient use of raw materials; the ability to sell the product without ripening or with a short ripening period (no more than 14 days); and high quality indicators. In general, cheese is considered a complete food product that covers part of a person's daily needs for nutrients and biologically active substances. Due to martial law in the country, loyalty in the sale of products plays a unique role, but the temperature regime of storage affects the safety of cheese. Therefore, the study aimed to determine the sanitary quality of soft, fresh cheese and to justify the parameters of product storage at a temperature of 6 °C. The research was conducted at the Regional State Laboratory of the State Service of Ukraine for Food Safety and Consumer Protection in Poltava Oblast and at the Department of Livestock Products Processing Technology laboratory of Poltava State Agrarian University. The research objects were samples of soft, fresh cheese without fillers produced at the Milk Local Product Expert Center of the Faculty of Animal Production and Food Technology. The indicators stipulated by the regulatory document for soft cheeses 4395:2005 “Soft cheeses. General technical conditions”. It was established that the investigated cheese (sample No. 6) met the requirements of the current standard in terms of organoleptic (appearance, taste and smell, consistency, dough color, pattern, shape), physicochemical (mass fraction of fat, table salt, water) and physicochemical parameters. Specific physicochemical characteristics (mass fraction of moisture, table salt, and fat in dry matter) of the cheese, according to the tests, were within the limits specified by SSTC. The studied samples of fresh soft cheese regarding microbiological parameters (pathogenic microorganisms, particularly Salmonella, Listeria monocytogenes, and Staphylococcus aureus) complied with regulatory documents when they were stored at +6 °C for two days. At the same time, it has been proven that storage of fresh soft cheese without fillers at a temperature of +20 ± 0.5 °C leads to the growth and presence of coliform bacteria in the E. coli group. As early as 48 hours later, the products did not meet the regulated norms of the current national standards.