Whole Cluster vs Stem Inclusion in Chambourcin (2017)

This study examines the impact that fermenting with whole clusters or with stem inclusion has on Chambourcin wines. Chambourcin grapes were harvested from the same block on the same day and separated into 3 T Bins. One T Bin received 100% destemmed and crushed fruit (control). The second T Bin received 30% whole clusters at the bottom, and then was filled with 70% destemmed and crushed fruit (by weight). The third T Bin received 30% of the stems by weight from the control at the bottom of the T bin, and then were filled with the same weight of destemmed and crushed grapes as the control and treatment. All other treatments between musts and wines were identical. pH was slightly increased by whole cluster and stem inclusion, and TA and tartaric acid was slightly decreased. Pyrazine was slightly increased by the treatments. Color intensity was not much affected by the treatments. Catechin, epicatechin, and quercetin were slightly increased by the treatments. Tannin was increased by the treatments, and anthocyanins were decreased by the treatments. Overall, stem inclusion seemed to result in lower Bitterness, and may have lowered Astringency and Herbaceous/Green character. The whole cluster and the control treatments tended to be higher in Herbaceous/Green character. The intensity for the descriptors for whole cluster inclusion seemed to change over time, perhaps due to ester qualities decreasing over time in bottle. Preference trends were hard to determine, although whole cluster and stem inclusion wines tended to be more preferred over the control.

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Carbonic Maceration in Merlot (2017)

This study examines the difference in aroma, flavor, and mouthfeel produced from fermenting Merlot traditionally versus through carbonic maceration. Merlot grapes were harvested on September 27, and some was split into a macrobin while the rest was added whole cluster to a carbon dioxide-flushed stainless steel tank. The carbonic maceration treatment tank was flushed with carbon dioxide twice per day, and the tank was not opened for 7 days. After 7 days, the carbonic maceration whole clusters were removed, and destemmed into a T bin, where it also received a more traditional fermentation. Musts in T Bins received 2 punchdowns per day. Both T Bins (the traditional and the carbonic maceration one) were pressed off on the same day (October 19). All other treatments between wines were equal. The carbonic maceration wine had lower ethanol, higher TA, and higher succinic acid. Most higher alcohols and esters were higher in the carbonic maceration wine. Color and phenolics were lower in the carbonic maceration wine. There was a significant sensory difference between the carbonic maceration and traditional fermentation wines (p<0.001), with a slight preference for the carbonic maceration wine. These results suggest that carbonic maceration reduces Astringency and increases Ester Intensity and Overall Aromatic Intensity.

 

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Whole Cluster Inclusion in Merlot Fermentations (2016)

This study examines the impact of whole cluster inclusion on the sensory and chemical profile of Merlot. Merlot was harvested from the same vineyard block on the same day and processed identically except that one treatment was only 70% destemmed (not crushed) with the other 30% of fruit added as whole clusters. All other treatments were the same. Whole cluster inclusion did not affect wine chemistry, except for slightly increasing pH. Whole cluster inclusion lowered color intensity, anthocyanin content, quercetin, caftaric acid, and epicatechin. However, tannin and catechin content was slightly increased by whole cluster inclusion. Hue was also increased, due to the lower absorbance at 520. Judges found the wines to be significantly different (p<0.01), but no real preference trends could be seen between treatments. 30% whole cluster inclusion tended to score slightly higher in all attributes except for Fruit Intensity and Astringency, where it was the same as 0% whole cluster inclusion. However, the differences for these descriptors were very small, and more studies are needed to identify in what ways the wines can be described as different.

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Whole Cluster Inclusion in Cabernet Franc Fermentations (2016)

This study examines the impact of whole cluster/stem inclusion on the sensory and chemical profile of Cabernet Franc. Cabernet Franc was harvested from the same vineyard block on the same day and processed identically except that stem inclusion was performed so that either 100% of the fruit was destemmed but not crushed, 60% of the fruit was destemmed but not crushed (40% added as whole clusters), or 10% of the fruit was both destemmed and crushed and the other 90% was added as whole clusters. All other treatments were the same. The 40% Inclusion treatment was not tasted. Whole cluster inclusion did not affect wine chemistry. Color intensity and hue were both increased at 40% and 90% whole cluster inclusion. Cinnamic acids, catechin, tannin, and polymeric anthocyanins were also increased with 40% and 90% inclusion (although polymeric anthocyanins were not very different). Epicatechin and anthocyanins were lowered by 40% and 90% whole cluster inclusion. The results for 40% inclusion were taken at different time points, however, so may not be entirely representative. Judges found the wines to be significantly different, but there were no strong preferences for one treatment over another. 90% inclusion had a slight tendency to have higher Overall Aromatic Intensity and Fruit Intensity, but this was not seen at all tastings. More studies should be performed on whole cluster and stem inclusion to determine how to best vinify different treatments. This is especially true with regard to microbial stability, as well as finding optimal ranges of cluster/stem inclusion based on desired styles.

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Stem Inclusion in Cabernet Franc Fermentations (2016)

Cabernet Franc Grapes were hand harvested and then destemmed into three lots. The first lot contained no stems, the second lot had 5% stems included based on fruit weight, and the third lot had 10% stems included based on fruit weight (ie: 1 pound of stems for every 10 pounds of fruit in the 10% inclusion treatment). All other treatments between lots were the same. Phenolic and color profiles were not gathered for the 5% treatment. Additionally, because the 5% inclusion did not complete malolactic conversion, it was excluded from tastings. 10% stem inclusion did not result in many chemical differences between wines. Monomeric anthocyanins, quercetin, malvidin glucoside, and total anthocyanins were increased by stem inclusion, whereas tannin was decreased. This increase in anthocyanin, however, did not greatly alter color intensity, possibly due in part to the decrease in polymeric pigment. Overall, these wines were not found to be significantly different from each other. There were slight trends for the stem inclusion to increase Bitterness and Herbaceous/Green character, and reduce Body. This study should be repeated over several vintages, as well as with different grape varieties in order to better determine the full impact of stem inclusion with Virginia ripening conditions. Additionally, this would be an interesting project to see how the wine evolves over time, to see if differences grow over time.

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Whole Cluster Inclusion in Chambourcin Fermentations (2016)

This study examines the impact of whole cluster inclusion on the phenolic and sensory characteristics of Chambourcin wines. Chambourcin grapes sourced from the same block were either completely destemmed and lightly crushed (0% inclusion), 70% were destemmed and lightly crushed (30% inclusion), or 50% were destemmed and lightly crushed (50% inclusion). All other treatments between lots were the same. Increasing the amount of whole cluster inclusion tended to lower the ethanol content. Whole cluster inclusion tended to lower the color intensity and increase the hue, and this effect was more pronounced for higher levels of inclusion. All phenolic indices were lowered by whole cluster inclusion, but did not differ much between 30% and 50% inclusion. This was most noticeable with monomeric and total anthocyanins, as well as malvidin glucoside. Overall, whole cluster inclusion tended to increase Herbaceous/Green character in the wines. Descriptions of these wines were mixed, and most trends were weak and varied from tasting to tasting. No major preference trends could be seen across tastings. This study suggests that whole cluster inclusion could be a viable stylistic tool for Chambourcin wines, but much more work is needed to elucidate what impacts these kinds of treatments have on wine quality.

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Carbonic Maceration vs Traditional Fermentation in Merlot (2016)

This study examined the impact of carbonic maceration on the chemical and sensory qualities of Merlot in comparison to traditional fermentation. Carbonic maceration lowered all phenolic and color attributes in the wine. Most wine chemical parameters stayed the same, except that lactic acid was greatly increased in carbonic maceration. These results suggest that carbonic maceration reduces Body and Astringency compared to traditional fermentation. These results also suggest that the aroma in carbonic maceration changes greatly over a short period of time, as the Fruit Intensity and Ester Intensity of the carbonic maceration tended to more approach that of the traditional fermentation over time. Tasting order had a very large impact on descriptive analysis, so much of these results should be interpreted with care. Because the carbonic maceration wine is intended to be used as a blending component in red winemaking at this winery, in the future blending trials should be performed. Additionally, different carbonic maceration techniques should be employed, such as altering the temperature and time of carbonic maceration, or destemming berries at processing prior to maceration.

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Whole Cluster Inclusion with Cabernet Franc (2015)

Cabernet Franc was made with 0% and 25% whole cluster inclusion.  There were no chemical differences between wines in this study.  The wine made with whole clusters had less anthocyanins and pigment, and slightly less color intensity and greater hue.  There was no significant sensory differences between the wines, but people tended to prefer the wine with whole cluster inclusion.

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Whole Cluster Inclusion with Syrah (2015)

Syrah was vinified with 0% whole cluster inclusion, 25% whole cluster inclusion, and 75% whole cluster inclusion.  No real chemical differences were observed between wines.  Whole cluster wines tended to have higher tannin content but lower anthocyanin content.  This corresponded to a lower level of color intensity in those wines as well.  Most people preferred the 25% whole cluster inclusion, and most people did not prefer the 75% whole cluster inclusion.

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Whole Cluster Inclusion of Cabernet Franc (2014)

This study examines various stem inclusion and cap management methodology on Cabernet Franc.  One wine was 0% whole cluster inclusion and pressed at dryness, another was 30% whole cluster inclusion and pressed at dryness, and another was 100% whole cluster inclusion and pressed after 3 days.  Whole cluster inclusion slightly increased volatile acidity.  Color intensity decreased with increasing inclusion, as did hue.  In general, people preferred wines with less cluster inclusion.

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