Effect of alternative new pruning system and harvesting times on aroma compounds of young wines from Ecolly (Vitis vinifera) in a new grape growing region of the Weibei Plateau in China

Abstract

Each training system affecting the volatile concentration of wine is closely related to the specific growing conditions of grape. The aim of this work is to evaluate the influence of different training systems, such as crawled cordon training (CCT) and independent long-stem pruning (ILSP), on the volatile composition of Ecolly wine in Weibei Plateau region in three periods (July 31, August 10 and 24). Total aroma concentration (271.15mgL−1) and ethyl octanoate concentration (84.60mgL−1) were the highest for ILSP in August 24 in aroma compounds. However, total aroma concentration of CCT exceeded the ILSP in July 31 and August 10, respectively. ILSP could lead to higher acetate esters compared with CCT except for August 10. Ethanol esters were also strongly influenced by training systems in July 31 (CCT>ILSP) and August 24 (ILSP>CCT), except for slight influence in August 10. But other esters were not strongly impacted by training system. Despite the highest higher alcohols in ILSP in August 24, CCT still displayed significant higher concentration in the first two harvesting times than ILSP. Organic acids showed the same trend as higher alcohols in the experiment. Odor activity values (OAVs) of the 16 aromas compounds showed similar results. Results have shown that CCT improved the accumulation of aroma compounds in early wine, if harvesting time need to be postponed, ILSP was also a suitable select. Whereas, a strongly suggestion of CCT was made because stabilization of yield and quality could be guaranteed by CCT annually.