Monitoring of the betalain content dynamics in table beet (Beta vulgaris L.) during long-term storage

Background. The use of betalains as natural food colorants faces difficulties related to the stability of their chemical structure during storage and, consequently, their coloring ability. The relevance of the study is due to insufficient knowledge of the patterns of changes in betalain concentration during long-term storage. Materials and methods. The study analyzed 52 table beet accessions with intense red root color from the VIR collection. Quantitative measurement of betalains was carried out spectrophotometrically. Results and conclusion. The content of these pigments in the studied accessions ranged from 130 to 1526 mg/100 g dry weight, specifically: betacyanins varied from 82 to 1271 mg/100 g, and betaxanthins from 23 to 494 mg/100 g. Using cluster analysis, all accessions were divided into 4 groups depending on the total betalain content. Data were obtained on the monthly dynamics of betalain content in table beet roots during long-term storage. In the first month after harvesting and placing the roots into storage, an increase in betalain content of approximately 40% was observed. On average, pigment degradation during long-term storage was 28%. The decrease in betalains occurred mainly due to a reduction in the amount of betacyanins. Among the studied accessions, cv. ‘Generalskaya’ (k-3894, Russia) is of greatest interest for obtaining the colorant immediately after harvesting and in the first month of storage. Cvs. ‘Kombat’ (k-4032, Russia) and ‘Marusya’ (k-3982, Russia) turned out to be the most stable sources of the pigment throughout the entire storage period.