The Effect of Different Aging Vessels on the Sensory Qualities of Viognier (2016)

This study examines the effects of aging Viognier wine in concrete eggs, stainless steel barrels, and acacia barrels on the chemical and sensory qualities of Viognier. One lot of Viognier wine was split into these different aging vessels after a week of fermentation. The wine was aged in these vessels for approximately four months. No chemical differences could be found between wines, except that acacia barrels exhibited the lowest levels of dimethyl sulfide. Aging in acacia barrels tended to reduce Fruit Intensity and Overall Aromatic Intensity and increase Yeast Character. Stainless steel and concrete egg aging tended to help maintain Fruit Intensity and Aroma. In general, aging in acacia barrels was least preferred compared to other treatments. More studies on these different aging vessels should be performed, perhaps with different aging times and types of wine.

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Chardonnay Lees Management with Extralyse (ARC) (2016)

This study examined the impact of lees stirring and batonnage enzyme addition during Chardonnay aging on the chemical and sensory qualities of the wine. Chardonnay juice was fermented in barrels, and afterwards 3 different stirring regimes were imposed: unstirred, stirred, and stirred with Extralyse (Laffort). Stirring occurred once per week for 8 weeks. The finished wines showed decreasing levels of residual sugar with stirring and with enzyme addition. Some malolactic fermentation could be observed in the stirred wine with Extralyse as well. Wine tended to become more cold stable over time, but the unstirred wine showed the highest level of cold stability but also the highest level of bentonite addition necessary to become heat stable. These results suggest that stirring may enhance Sweetness, Depth of Flavor, Yeast Character, and Body, although many of these effects were weak. The effect of Extralyse in combination with stirring was not too different than from stirring itself. However, the stirring regime for this study was relatively short (8 weeks). In the future, more realistic stirring regimes should be implemented to see whether differences tend to increase over time, particularly with respect to Extralyse.

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Chardonnay Lees Management with Extralyse (ARC) (2016)

This study examined the impact of lees stirring and batonnage enzyme addition during Chardonnay aging on the chemical and sensory qualities of wine. Chardonnay juice was fermented partially in tank before being aeratively racked with lees inclusion to finish fermentation in barrels, and afterwards 2 different stirring regimes were imposed: unstirred and stirred with Extralyse (Laffort). Stirring occurred once per week for 8 weeks. No major chemical differences could be observed between treatments, and both wines underwent partial malolactic conversion. Wines tended to become more cold stable and heat stable over time, with stirring and Extralyse potentially making the wine slightly more heat stable than not stirring. Of 10 judges, 9 were able to correctly distinguish the wines from each other, showing that these wines were significantly different (p<0.001); however, this may have been because the stirred wine was cloudy. 8 out of 8 people tended to prefer the wine with Extralyse; however, the unstirred wine may have had some oxidized characteristics. Wine produced with Extralyse and Stirring had a strong tendency to be higher in Sweetness and Body, and tended to have slightly higher Yeast Character and Depth of Flavor. However, the stirring regime for this study was relatively short (8 weeks). In the future, more realistic stirring regimes should be implemented to see whether differences tend to increase over time.

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Chardonnay Lees Management (2016)

This study examined the impact of lees stirring during Chardonnay aging on the chemical and sensory qualities of the wine. It is a companion study to Blenheim’s Chardonnay Lees Management with Extralyse (ARC) study (2016). Chardonnay juice was fermented in sets of barrels, after which one was left unstirred while the other was stirred during aging. Stirring occurred once per week for 8 weeks. No major chemical differences could be observed between the finished wines. Wine tended to become more cold stable over time, but the unstirred wine required the lowest bentonite addition to become heat stable. Additionally, increasing bentonite additions to become heat stable were necessary after aging. This study suggests that stirring has a noticeable effect on finished wine, but this effect is not necessarily preferred or disliked (perhaps a slight preference towards stirred wines). The descriptors used generally did not help elucidate which qualities in wine were affected by stirring. Some trends seemed to result from stirring, such as a potential increase in body, yeast character, and depth of flavor. Bitterness may have been slightly decreased as well. However, no firm conclusions can be drawn in these regards. The stirring regime for this study was relatively short (8 weeks). In the future, more realistic stirring regimes should be implemented to see whether differences tend to increase over time.

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Chardonnay Lees Management with Extralyse (ARC) (2016)

This study examined the impact of lees stirring and batonnage enzyme addition during Chardonnay aging on the chemical and sensory qualities of the wine. It is a companion study to Blenheim’s Chardonnay Lees Management (2016), which compared the effects of not stirring Chardonnay to stirring Chardonnay. Chardonnay juice was fermented in barrels, and afterwards two different treatments were imposed: stirred, and stirred with Extralyse (Laffort). Stirring occurred once per week for 8 weeks. No major chemical differences could be observed between the finished wines. Wine tended to become more cold stable over time. Additionally, increased bentonite additions to become heat stable were necessary after aging. In general, people often could not distinguish between stirring and stirring with Extralyse. When people could distinguish, there appeared to be a slight preference for wine made with Extralyse. The descriptors used generally did not help elucidate which qualities in wine were affected by stirring. There may be a small tendency for Extralyse to enhance Fruit Intensity and Depth of Flavor, but these tendencies were weak. However, the stirring regime for this study was relatively short (8 weeks). In the future, more realistic stirring regimes should be implemented to see whether differences tend to increase over time.

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Concrete vs. Stainless Steel Aging with Sauvignon Blanc (2014)

This study compares the chemical and sensory effects of aging Sauvignon Blanc wine in concrete and stainless steel vessels.  Although there were no chemical differences between the wines, there were significant sensory differences between the wines.  This seems due in part to the stainless steel-aged wine being slightly oxidized, but there were reports of the concrete egg-aged wine having a creamier and fuller mouthfeel.

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