CHANGES IN THE CHEMICAL COMPOSITION OF CRANBERRY BERRIES LARGE-FRUITED DURING STORAGE

Abstract

Large cranberry is a valuable food and medicinal plant. The early cultivar «Bergman» and mid-season cultivars «Ben Lear» and «Pilgrim», the most promising for southern West Siberia, ripen rather late – in the second-third decades of September. The aim of the work was study of the chemical composition of large cranberry berries and its dynamics during long storage. In this regard, biochemical study of dry substance, ascorbic acid, sugars, acids, anthocyans, catechins, pectins and protopectins of berries promising cultivars was conducted. The chemical composition was analyzed by conventional methods. It was established that the early cultivar «Bergman» compared to mid-season cultivars «Ben Lear» and «Pilgrim» accumulated more ascorbic acid and anthocyans. In the course of long (5–6 months) storage of fruits in the refrigerator the decrease in the number of sugars, ascorbic acid and pectins (partially) took place in all cultivars, but the content of dry substance, acids, protopectins (1.2–2.9 times) and anthocyans (1.7–5.0 times) increased. Therefore, it is possible to after-ripen unripe cranberry berries. On accumulation of anthocyans and protopectins Siberian samples are close to or exceed Belorussian ones which form a qualitative fruit composition in more favourable conditions. To receive high-quality by biochemical indices production, it is necessary to grow early large cranberry cultivars in southern West Siberia, to harvest berries in the late second-third decades of September when berries acquire natural color and to store fresh berries in the refrigerator for not more than half a year.