Phenolic profile of blackberry wine produced using Korean winemaking techniques in earthenware jars

This research evaluated the winemaking potential of ‘Natchez’ and ‘Triple Crown’ blackberries grown in Oklahoma and examined the phenolic composition of blackberry wines made using modified Korean traditional winemaking techniques. The winemaking variables were fermentation temperature (21.6 vs 26.6°C), and fermentation type (yeast inoculation vs wild fermentation). High‐performance liquid chromatography was used to examine the phenolic compounds in blackberry juice and wine. The phenolic compounds consisted of anthocyanins (kuromanin, keracyanidin, delphinidin) and phenolic acids (gallic acid, catechin, caffeic acid, epicatechin, p ‐coumaric acid). The ‘Natchez’ berries had higher concentrations of anthocyanins (kuromanin) while ‘Triple Crown’ berries had higher levels of phenolic acids ( p ‐coumaric acid). For many compounds, a higher fermentation temperature generally corresponded to higher concentrations of the phenolic compound in the wine after three months aging, but this was not universally observed. Accordingly, fermentation temperature may best be matched with individual cultivars via experimentation in order to maximise extraction and retention of phenolic compounds in the finished wines. Overall, the Korean traditional winemaking technique may be a good technique to add value to wines made from blackberries suited for production in a mid‐continental climate such as the central USA. © 2018 The Institute of Brewing & Distilling