A. M. Taspolatova

This paper presents the results of a study examining the effect of infrared drying on the preservation of biologically active substances and minerals in melons—watermelon of the 'Asar' variety, melon of the 'Kolkhoznitsa' variety, and pumpkin of the 'Aphrodite' variety—grown in southern Kazakhstan. Key chemical composition parameters were determined before and after drying, including dry matter content, total sugars, vitamin C, lycopene, β-carotene, and phenolic compounds, calculated on a dry matter basis. The preservation rate of phenolic compounds was found to be 88–93%, β-carotene—86–87%, and vitamin C—75–80%, demonstrating the gentle nature of infrared drying and the high preservation of antioxidant components. The mineral composition of the dried plant materials was also studied. It was shown that watermelon, melon, and pumpkin retain significant amounts of macro- and microelements (K, Ca, Mg, Fe, Zn), while the mineral concentration on a dry matter basis increases 6-10 times compared to fresh samples due to moisture removal. The study results demonstrate that infrared drying is an effective method for producing concentrated and stable powders from melons, preserving their biologically valuable and mineral components. The data obtained can be used in the development of technologies for functional foods and natural ingredients based on local plant materials from Kazakhstan.

This article provides information about the method of obtaining potassium humate obtained from brown coal of the Lenger deposit, and also describes the elemental and mineralogical composition of potassium humate determined with SEM (JSM-6490l V, Jeol). Kinetic data on the decomposition of brown coal with solutions of potassium hydroxide are presented. The area of chemical reactions and the activation energy are determined. The benefits of the obtained potassium humate are that they are environmentally safe and have high bioactivity. They are also characterized by a high content of humic substances that are involved in the structure formation of the soil, accelerate biochemical processes, and increase the physical and chemical characteristics in the soil. Under the influence of humate-containing substances, the function of microflora elements in the soil is activated, and the number of beneficial microorganisms increases.