Dynamics of changes in the content of betalain pigments in red beet roots during the growing season and storage

Purpose. Betalains, plant pigments of red beet roots, exhibit antioxidant activity and reduce the risks of many pathological conditions. However, the widespread introduction of betalains is hampered by insufficient knowledge of their transformations during the growing season and storage of root crops, which was the purpose of the work. Methods. Root crops of five varieties of table beets were used in the studies. The content and stability of betalains were determined by spectrophotometric methods according to the numerical indices of the absorption spectra of extracts from root crops. Results. In the beet roots in the first 20 days of vegetation after germination, the content of betaxanthines is higher than that of betacyanins, but by the 40th day, betacyanins exceed betacyanins over betaxanthin in the ratio of 1.26-2.21. By the 70th - 90th days of vegetation, the main pool of betalains is formed, their content reaches 84.5-198.6 mg / 100 g, the ratio of betacyanins / betaxanthins and resistance are 2.47-9.76 and 0.82-0.91 respectively. The highest excess of the content of betacyanins over betaxanthins by 8.11 - 9.65 times was obtained in beet root crops of Creolka and Veselaia Smulyanka varieties. The stability of betalains during six-month storage decreases less than 1.4 times. Conclusion. It is advisable to use the developed spectrophotometric method for determining the stability of betalains in the express analysis of beet root crops. Betalains are more stable than other plant antioxidants. Beet roots are more preferred for fortifying diets than other foods with antioxidant activity.