Microwave maceration for finished Pinot noir wine in 37 days

The aim of this research was to generate proof of concept for rapid red winemaking from microwave maceration. Microwave maceration had previously proven effective for rapid extraction of phenolic compounds from Pinot noir grape solids into juice. Microwave maceration was applied to 1kg lots of must, which were pressed-off after three hours total skin contact time. This reduced the volume of must in the fermentation vessel by approximately 40%. Due to the pasteurising effect of microwave maceration, SO2 was omitted at crushing and this enabled immediate co-inoculation for simultaneous alcoholic (AF) and malo-lactic fermentation (MLF). The Oenococcus oeni strain PN4 (Lallemand) was applied for MLF, in conjunction with one of three yeast strain treatments: Saccharomyces cervisiae RC212, S.cerevisiae EC1118 and S.bayanus AWRI1176 (Lallemand). Each of these yeast strains proved to be compatible with PN4, and all replicates had completed AF and MLF within 17 days of inoculation. While The three yeast treatments delivered distinct phenolic outcomes in finished Pinot noir wine. At six months bottle age, RC212 wines were significantly higher in mean concentration of free anthocyanin than AW1176 wines (255 AU and 222 AU, respectively) and RC212 wines were significantly lower in mean concentration of pigmented tannin than AW1176 wines (0.41 AU and 0.74 AU, respectively) and wines from the three yeast treatments were equivalent for mean tannin concentration. Wines from this trial were settled, stabilised and bottled by 37 days post-harvest. Microwave maceration and early press-off were demonstrated to be effective for rapid red winemaking, and to warrant further investigation on a larger scale.