Study of the influence of various factors on the intensity of coloring of anthocyanin solutions for the purpose of using these solutions as coloring substances of biomaterials

Anthocyanins, a large class of organic compounds comprising plant polyphenols, are naturally occurring pigments. In plants, anthocyanins have been shown to exert a positive influence, enhancing drought and frost resistance, promoting pollination through vibrant floral coloration, and bolstering resistance to diverse diseases. Plant pigments, anthocyanins, have continued to be a great interest because of their safety and practical benefits in improving human health. In this study, anthocyanin solutions were prepared from red cabbage, blue violet flowers, blueberry skins, and viburnum berry juice. Specific conditions for the preparation of these solutions were selected and described. Notably, a solution can be readily prepared by combining 30-60 g of finely chopped red cabbage with 100 ml of boiling distilled water; the resulting solution is ready for research purposes after cooling to room temperature. The study also defines the quantity of anthocyanin solutions for change in color. It has been determined that as little as six drops of anthocyanin solutions introduced into 15 ml of the tested solutions is sufficient. The influence of various factors on the change in the color intensity of anthocyanin solutions was investigated by observing the change in the optical density of the studied solutions using a blue light filter with a wavelength of 415 nm. It has been established that the optical density of anthocyanin solutions in acidic and alkaline increases in comparison with a neutral medium, and in an alkaline medium there is also a change in the color of the studied solutions. In contrast to the solution obtained from the juice of viburnum berries, a similar regularity of changes in optical density from the reaction of the medium of anthocyanin solutions obtained from red cabbage, blue violet flowers, and blueberry berries was observed. It was shown that under equal conditions, the intensity of the color of the studied solutions increases with an increase in the number of anthocyanin solutions applied. It has been established that the change in the intensity of the color of anthocyanin solutions is not affected by the basicity of acids or ultraviolet irradiation for 3 hours. The possibility of using anthocyanin solutions from red cabbage and blueberry skin as coloring pigments for dyeing genuine leather, cotton and woolen threads, and moss has been investigated. It was revealed that the deepest coloration of the samples is observed when staining with solutions from the skin of blueberries. As is well know, anthocyanin solutions are good antioxidants; therefore, the introduction of red cabbage or blueberry skin solutions into foods, such as milk or sour cream, undoubtedly increases the nutritional value of the products consumed. Good compatibility of anthocyanin solutions with milk and sour cream has been shown. The introduction of small amounts of citric acid or baking soda into anthocyanin solutions makes it possible to obtain dairy products with different intensities of color. To reduce the effect of dilution of milk when adding a solution of anthocyanins from red cabbage, it is proposed to pour boiling milk over finely chopped red cabbage. Multicolored jelly from dairy products with anthocyanin solutions could be obtained. An increase in antioxidants components may also occur.

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