Abstract
Modern approaches to food storage require the use of safe and effective methods for extending shelf life without compromising quality. One such method is ozone treatment, which has pronounced antimicrobial and antioxidant properties. In the context of the increasing demand for high-quality nuts with a long shelf life, it is important to study the effect of ozonation on their stability under various temperature conditions. The purpose of this study was to examine the effect of ozone treatment and storage temperatures (10°C and 25°C) on the physicochemical, microbiological, and organoleptic characteristics of walnuts of the ‘Kazakhstani Early-Maturing’ variety. Attention was primarily paid to the assessment of such indicators as the acid number, iodine number, peroxide number, moisture content, and toxic elements, as well as microbiological contamination. The significance of the work was in clarifying the effect of ozone on the stability of the nut lipid complex and the development of microflora during storage. The practical value of the study was in testing the applicability of a safe pre-treatment method that would help maintain the quality and safety of nut products. The methodology included treatment in sealed containers at an ozone concentration of 0.50 mg/m³ for 30 min, followed by storage at two temperatures. The results of the chemical, organoleptic and microbiological analyses showed that ozonation significantly reduced microbial contamination, stabilized the lipid components and slowed the development of oxidative processes, especially with storage at 10°C. The organoleptic properties of the nuts were maintained at a high level, with no signs of rancidity, changes in taste or smell. In confirming the effectiveness of ozone treatment as a means of improving the quality and safety of nut products, this study contributes to the field of nut storage technologies, and our findings can be used in developing regulations for the storage of nuts and other oil-containing crops.