The valorization of the physico-chemical indicators of certain vegetable oils, comparative aspects, and the practical use of walnut oil

Vegetable oils represent valuable sources of nutrients, having a complex composition. These are natural products obtained through the extraction of lipids from seeds, nuts, or fruits and are mainly composed of triglycerides, essential fatty acids, fat-soluble vitamins (A, D, E, K), and natural antioxidants, such as tocopherols, which protect against oxidative stress. This paper presents the results of a study dedicated to the analysis of physicochemical indicators for four types of vegetable oils: walnut oil (the varieties "Codrene," "Pescianski," and "Chandler"), coconut oil, flax oil, and grape seed oil. The study includes a comparative analysis of the main parameters (acidity index, iodine index, and peroxide index) before and after thermal processing. Based on the conclusions, an innovative method was proposed for using walnut, flax, coconut, and grape oils in the manufacture of high-quality soap.