Influence of juice processing factors on quality of black chokeberry pomace as a future resource for colour extraction.

Aronia melanocarpa berries are a rich source of anthocyanins and its pomace, a by-product of juice processing, could be efficiently used for extraction of natural colours for the food industry. This study evaluated the influence blanching, freezing, maceration temperatures (2°C, 50°C) and enzyme treatments before juice pressing on the yield and anthocyanin composition of both juice and pomace. Total anthocyanin levels in pomace were affected mostly by enzyme treatment followed by maceration temperature.

Phenolic compounds in blackcurrant (Ribes nigrum L.) leaves relative to leaf position and harvest date.

Blackcurrant leaves are an essential source of phenolic compounds and this study investigated their variation relative to leaf positions and harvest date. The phenolic content varied between harvest dates, although leaf position on the shoot and interactions also played an important role. The contents of quercetin-malonyl-glucoside, kaempferol-malonyl-glucoside isomer and kaempferol-malonyl-glucoside were higher than that of the other identified phenolic compounds, whereas epigallocatechin was the lowest for all investigated leaf positions and harvest dates.

Phenols and ascorbic acid in black currants (Ribes nigrum L.): variation due to genotype, location, and year.

Black currant berries contain many biochemical compounds with proven or potential human health benefits. We studied the content of total and single polyphenols, ascorbic acid, soluble sugars, and titratable acidity for two advanced selections and three cultivars of black currant at two distant locations in Sweden (south: 56°06'N; north: 65°21'N) over a 3 year period. Regression analyses revealed the effect of genotype to be considerably larger than that of location and year.

An optimized method for analysis of phenolic compounds in buds, leaves, and fruits of black currant ( Ribes nigrum L.).

Although the fruits are the economic driver for the black currant industry, the buds and leaves are excellent sources of beneficial phenolic compounds that may contribute to the future value of the crop. In this study, extraction of phenolic compounds for different parts of the black currant plant was optimized, and an efficient method for their separation by HPLC was developed. This allowed the simultaneous quantification of a range of hydroxycinnamic acids, flavan-3-ols, flavonols, and anthocyanins by DAD following their identification by HPLC-ESI-MS(n).