The Stylistic Impact of Different Cap Management Procedures in Cabernet Franc

Summary

Decisions as to the type and duration of cap management during red wine fermentation can have a significant impact on aroma, flavor and chemistry of the resulting wine. Punching down and pumping over bathe the cap in liquid, help minimize microbial spoilage, introduce oxygen to the fermentation, dissipate temperature buildup and reduce saturation of extracted phenolics. The purpose of this study was to compare the effects of gentle punch downs with short pump overs in Cabernet Franc. The winemaking goal for this wine was to produce an early bottling fruit forward style. Punch downs resulted in a slightly warmer cap temperature that was not fully integrated by cap management. Slightly higher levels of phenolics were seen with punch downs vs. pump overs. In a triangle test, 17 out of 28 respondents were able to distinguish these wines, indicating the wines were significantly different (Z=2.873, p=0.002). However, there were no significant differences in scores for fruit intensity, astringency or herbal/green character.

Read full report (pdf)

Punchdown vs. Pumpover.png


The Effect of Different Cap Management Techniques on Merlot Wine (2016)

This study examines the effect of different cap management techniques on the chemical and sensory qualities of Merlot wine. Merlot grapes were harvested on the same day and split into 3 separate 1-ton T bins with three different treatments: 2 punchdowns per day, 4 punchdowns per day, and 2 pumpovers per day. The timing between 2 punchdowns and pumpovers were approximately 5-8 hours apart, and the timing between 4 punchdowns was approximately 1-2 hours apart. Increasing punchdowns and pumpovers increased the pH (5% and 22% lower proton concentration, respectively) and pumpovers slightly decreased TA. The treatments also increased the volatile acidity and increased the sulfur dioxide binding capacity of the wine. Increasing the number of punchdowns had the greatest impact on color, catechin, and tannin accumulation, although pumpovers slightly increased this as well. Anthocyanins were decreased by the treatments, especially with the 4 punchdown treatment. Overall, these wines were not perceived to be very different from each other. The 2 Punchdown wine seemed to be slightly more preferred than the rest of the treatments, but this was a weak preference. Descriptive analysis from both tastings suggest that the 2 Punchdown wine may have been slightly lower in Astringency, Bitterness, Body, and Herbaceous/Green character. However, if so then this was a very weak trend.

Read Full Report (PDF)

Different Maceration Techniques in Cabernet Franc (2015)

Cabernet Franc was fermented in three separate ways.  The control received no cold soak nor extended maceration.  One wine was fermented in the Maceration a Chaud du Marc style, where fermenting juice was racked into another tank where the temperature was kept around 20C (70F), the skin was left in the Tbin and temperature was brought up to 42C (107F) until the juice reached a specific gravity of 1.020 and was blended back with the skin.  The third wine received both a cold soak and extended maceration.  No chemical differences were observed between wines, except that the wine with cold soak and extended maceration had higher pH, lower TA, and lower ethanol.  Maceration a Chaud du Marc slightly increased polymeric pigment and color, and slightly decreased hue.  People tended to prefer the Maceration a Chaud du Marc, in spite of being described of having some typical Brettanomyces aromas.

Read Full Report (PDF)

Cap Management Comparison with Merlot (2015)

Four Merlot wines were made with varying cap management regimes (all wines were destemmed): 2 punchdowns per day, 4 punchdowns per day, 2 punchdowns per day in addition to being crushed, and 2 pumpovers per day.  There were no real chemical, phenolic, or microbial differences between treatments except that the wine with pumpovers had slightly higher volatile acidity.  People tended to prefer the wine made from crushed grapes with two punchdowns per day.

Read Full Report (PDF)