RT Journal Article SR Electronic T1 Effect of Pump-over Conditions on the Extraction of Phenolic Compounds during Cabernet Sauvignon Fermentation JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP ajev.2018.16103 DO 10.5344/ajev.2018.16103 A1 Larry A. Lerno A1 Siriwan Panprivech A1 Ravi Ponangi A1 Leanne Hearne A1 Tom Blair A1 Anita Oberholster A1 David E. Block YR 2018 UL http://www.ajevonline.org/content/early/2018/03/09/ajev.2018.16103.abstract AB The formation of the cap during red wine fermentation necessitates some mode of cap management be employed so that proper control of fermentation temperatures can be maintained and phenolic extraction can be promoted during the course of alcoholic fermentation. One of the most common forms of cap management are pump-overs, in which fermenting juice is pumped from below the cap and sprayed over the top of it. The efficacy of pump-overs at maintaining temperature and promoting phenolic extraction is thought to be affected by both the volume and frequency of pump-over, but these effects have not been thoroughly investigated in a highly-controlled environment. Research-scale Cabernet Sauvignon fermentations (100 L) were performed in which the volume and frequency of the pump-overs were systematically varied and phenolic extraction was monitored during fermentation. Pump-over volume and frequency were found to have no significant effect on phenolic extraction in research-scale fermentors and the minimum mixing needed to maintain phenolic extraction and temperature control was half of the fermentor volume twice per day. The results obtained may be dependent on fermentor size or design. Analysis of the bottled wines for phenolic content five months post-treatment showed no significant differences.