This study examines the impact of whole cluster inclusion in Syrah fermentations. Syrah grapes from the same vineyard block were harvested and processed into T bins. One T Bin received fruit that was completely destemmed, whereas the other received 30% whole cluster inclusion. All other treatments between wines were identical. Each wine received a 6 day cold soak, and then afterwards were inoculated with RX-60 and received 2-3 punchdowns per day for 4 days in order to limit tannin extraction. Wines macerated for 17 days total, including cold soak. There were no differences in cold soak or in wine chemistry between treatments. Color intensity was higher in the whole cluster treatment, even though anthocyanin and quercetin parameters were slightly lowered by whole cluster inclusion. Catechin was increased in whole cluster inclusion. No significant sensory differences were found for these wines via triangle testing. No discernable preference trends could be seen in this tasting. For the descriptive analysis, there were no strong trends for the descriptors used in this study. There was a slight tendency for whole cluster inclusion to increase Fruit Intensity and decrease Herbaceous/Green Character. More studies should be performed on the impact of whole cluster inclusion in Virginia Syrah, and different rates of inclusion should also be examined.
This study examines the impact of whole cluster fermentation versus more traditional fermentation techniques in Petit Verdot winemaking. Petit Verdot grapes were harvested and processed into two T Bins. One treatment was completely destemmed, whereas the other treatment was 100% whole cluster inclusion. The 0% inclusion treatment was punched down, whereas the whole cluster treatment was stomped for punchdowns. When the 0% treatment reached approximately 8 Brix, the fermenting wine was delestaged and the pomace was stomped, and the wine was then racked back into the stomped pomace. Wine was pressed 16 days after processing. Juice and wine chemistry were very similar between treatments, except TA was slightly lower in the whole cluster treatment. Color was slightly increased, and many phenolic compounds were increased by whole cluster inclusion. Although anthocyanin was lower from whole cluster treatment, polymeric anthocyanins were increased. Overall, these wines were not found to be significantly different. There may have been a slight preference for the whole cluster wine. The whole cluster wine tended to score higher in Bitterness, Astringency, and Fruit Intensity. The whole cluster inclusion treatment had the clusters stomped during T Bin filling, which may have reduced some of the more estery characteristics often seen in whole cluster winemaking. Thus, these results may be more in line with what would be expected with a stem inclusion wine, rather than a purely whole cluster wine. This study suggests that whole cluster inclusion may be a useful method for creating a Petit Verdot which could serve as a valuable blending component, but more studies on whole cluster Petit Verdot are needed to determine whether any strong trends can be seen between treatments over time.
This study examines the impact of whole cluster inclusion on Cabernet Franc wines. Cabernet Franc grapes were harvested and processed into T bins. One T bin received 100% destemmed grapes, and the other received 100% whole clusters. The destemmed treatment was punched down twice daily, and the whole cluster treatment was stomped. After 18 days of maceration, wines were pressed off. The whole cluster wine fermented slower than the destemmed wine. Ethanol content, potassium, and lactic acid were also higher in the whole cluster wine. Color and anthocyanin were lowered in the whole cluster wine, while catechin and gallic acid were increased. Tannin may have slightly increased in this wine as well, but this is a weak result. For the triangle test, of 26 people who answered, 11 people chose the correct wine (42%), suggesting that the wines were not significantly different. In general, people who answered correctly did not show strong preferences for one wine over the other. For the descriptive analysis, there were no strong trends for the descriptors used in this study.
This study examines the impact of different winemaking styles on resulting Norton wine. Norton grapes were harvested over two days, and on the first day whole cluster, undamaged grapes were placed into a CO2-purged stainless steel tank with dry 71B yeast on the bottom (this yeast promotes ester formation) while on the second day grapes were destemmed and crushed into multiple T bins. This carbonic maceration tank was gassed with carbon dioxide daily throughout the maceration (approximately 17 days) and held at 65°F. The grapes were then pressed on November 6, and the press fraction was separated, inoculated, and fermented to dryness. The other treatment was punched down twice per day in T Bin throughout fermentation, and the T bins were inoculated with a mix of Lalvin C and Clos yeasts. The T Bins were pressed off on November 3. The carbonic maceration wine has higher alcohol, pH, and VA, with lower TA and lactic acid. The carbonic maceration wine has higher color and phenolic parameters, except for catechin. In sensory analysis, 58% of judges were able to correctly distinguish the wines, suggesting that the wines were significantly different (p<0.01). People who were able to distinguish the wines tended to prefer the carbonic maceration wine. There was a strong trend for the carbonic maceration wine to have higher Body than the traditional fermentation wine. There was a slight tendency for the carbonic maceration wine to have higher Ester Intensity. More studies should be performed on carbonic maceration in Norton and other non-vinifera grape varieties. Additionally, more studies should examine the evolution of aroma and flavor of these wines over time, and how this impacts overall consumer preference.
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.
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.
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.
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.
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.
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.
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.
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.
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.
In this study, 0% and 30% whole cluster inclusion Cabernet Franc were compared. There were no chemical or phenolic differences between these wines, as they exhibited low levels of extraction. Sensory results were not significant, although people tended to prefer the wine without whole cluster inclusion.
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.