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w i inneeGMAKIN GG w R O WIN Cabernet Sauvignon must underwent cold maceration for 48 hours, prior to yeast addition. The effect of fermentation on reducing sugar concentration and percent alcohol (v/v) at various sampling periods was determined by comparing one fermentation vessel each of délestagea nd pige age -pro duce d Cab er ne t Sauvignon (Figure III). While the fermentation rates were generally similar between treatments, some differences in the wines were noted. There were no differences in alcohol percent (v/v), TA, pH, tartaric, malic or lactic acids, between pigeage and délestage-produced wines (Table IV). 0.80 0.70 * Pigment levels 0.60 0.50 Control Délestage ns G allic A cid (mg/ L ) C atechin (mg/ L ) E picatechin (mg/ L ) C aftaric A cid (mg/ L ) C affeic A cid (mg/ L ) Q uercetin (mg/ L ) Malv idin G lucoside (mg/ L ) Poly meric A nthocy anins (mg/ L ) Total A nthocy anins (mg/ L ) Monomeric A nthocy anins (mg/ L ) a 22a 23 14 11 14 8 30 34 100 50 C abernet S auvignon Pigeage Délestage 21 17 9 11 12 4 13 36 83 28 55 49 29 <1 16 3 20 36 71 25 37 39 16 6 20 3 21 41 61 30 n=3 Total tannin, total phenols and total anthocyanins were greater in pigeageproduced wines. Differences in absorbance at 420 nm + 520 nm, and 420 nm/520 nm, were noted between délestage and pigeage. Table II provides the concentration of selected phenol compounds on aged Cabernet Sauvignon. Significant differences among treatments were not observed. Tannin concentrations remained stable until active fermentation, then increased and were higher in pigeage-produced wines at most sample periods (Figure IV). Total phenols (AU 280) increased for both treatments during pre-fermentation maceration, and significantly during fermentation (Figure V). At dejuicing, the total phenol concentration in the press wines averaged 14.5% and 9.8% higher than free run for délestage and pigeage wines, respectively (data not shown). At the completion of fermentation, free-run pigeage-produced wines had higher absorbance at 420 nm + 520 nm, and lower 420 nm/520 nm absorbance than délestage wine (Table IV). During the cold soak period, the per- 200 16 180 14 160 12 140 10 120 100 8 80 6 * * M erlot Control Délestage 60 * 0.40 4 * 40 0.30 0.20 0.10 * * * MP SPP LPP season 1 MP SPP LPP season 2 RS (g/L) Cabernet Sauvignon results Table I I : Mean values of HPLS analysis of phenolic profiles of aged Merlot wines (for three seasons), and C abernet S auvignon wine (produced one season). S ignificant differences were not observed at p ≤ 0.05. % Ethanol between délestage and control wines. Table II provides the concentration of selected phenolic compounds on aged Merlot determined by HPLC analysis. Significant differences among treatments were not observed. Catechin and epicatechin concentrations averaged 37 and 26 mg/L for the control and délestage-produced wines, respectively. Merlot total glycosides increased by day-2, the first day of fermentation (Table III). By the completion of fermentation (dejuicing), the total glycoside concentration had increased by an average of 388% and 296% for the control and délestage wines, respectively. At dejuicing, the total glycoside concentration was greater in the c ontrol wines. Phenol-free glycosides increased by day-two. They generally declined by the end of fermentation, and were in greater concentration in the délestageproduced wines at dejuicing. Results of discrimination sensory analysis suggested that Merlot wines were perceived to differ in aroma and/or flavor in two of three years. MP SPP LPP season 3 Figure II. Effect of control (cap punched) and délestage on Merlot — percent color derived from monomeric pigments (MP), small polymeric pigments (SPP), and large polymeric pigments (LPP) for three seasons; n = 3. 48 p r acti c al w i ne ry & v i ne yard JANUARY 20 14 2 20 0 0 1 Cold soak Punch ethanol 2 3 4 5 6 8 1 12 15 Fermentation/post-fermentation day Délestage ethanol Punch reducing sugar 17 22 24 Délestage reducing sugar Figure III. Effect of mechanical punch (pigeage) and délestage on Cabernet Sauvignon ethanol production and reduced sugar decrease; n = 3.