Accentuated Cut Edges (ACE) maceration reduces skin particle size thereby increasing the rate of extraction of components from grape skins. Subsequently, the wine can be pressed earlier (PE) than usual, and the fermentation completed in a smaller tank to make PE-ACE wine. The technique optimises fruit characteristics and saves time, space and labour in the winery. ACE maceration was tested on five red wine grape varieties at six commercial wineries located in four Australian states. PEACE treated wines had similar phenolic composition and sensory scores to the untreated wines. ACE maceration has the potential to significantly improve processing efficiency, profitability and competitiveness in the global market.
An earlier AGWA-funded project (UT1301) pursued the practical application of reducing the skin particle size of wine grapes during vintages 2014 and 2015, with very good results. Presentation of the research at the ASVO seminar and the CRUSH symposium in November 2015 brought enquiries from winemakers from a number of wine growing regions as to how they might access the technology. The technology was subsequently taken from state to state during vintage 2016. Winemaker networks were used to confirm participants at six wineries from four states investigating the response to ACE maceration of red wine varieties: Grenache, Merlot, Shiraz, Cabernet Sauvignon and Tempranillo. In total, eight separate ACE trials were conducted during vintage 2016. The trials included a control (the standard commercial treatment applied by the winery) and an ACE treatment (grape skins fragmented by a cutting device fitted into the must line between the crusher and the fermentation tank). The majority of winemakers elected to pursue the early press off option for ACE macerated wine, with the intention of reducing the time in the fermentation tank. These ‘pressed early’ (PE) ACE wines were referred to as ‘PEACE’ wines. The winery trials showed that ACE maceration in combination with early press off has considerable potential as a technique to help commercial winemakers manage compressed vintages. There were no significant differences in wine scores and both fruit and mouthfeel characteristics were somewhat improved. Reducing the time in the fermentation tank by 25 to 50% is likely to provide significant advantages for the Australian wine industry. Added to this are the savings in labour and energy costs as cap management requirements are also reduced in the production of PEACE wines. These savings have been outlined in project UT1301.