The Impact of Racking and Returning on Wine Quality (2017)

This study examines the impact of racking and returning during aging on red wine quality. Petit Verdot wine was split into two identical barrels. Once malolactic conversion was completed, one barrel was racked into tank, the barrel was pressure washed and ozonated, and then the wine was returned to the barrel and topped. The other barrel had no treatment. All other treatments between wines were identical. No major chemical differences were apparent between treatments. VA was slightly lower in the racked wine. Some sulfide parameters were lower in the racked wine, although whether these differences would impact flavor is hard to say. For the triangle test, of 20 people who answered, 7 people chose the correct wine (35%), suggesting that these wines were not significantly different. In general, of those who correctly identified the wines, 2 had no preference, 2 preferred the control, and 3 preferred the rack and returned wine. For the descriptive analysis, there were no trends for the descriptors used in this study. Judges commented that these wines were very extracted, which may have masked differences between wines. In the future, this study should be repeated on less intense grape varieties. Furthermore, the wine should be allowed to age more in future studies.

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The Impact of Lees Stirring on Red Wine Quality (2017)

This study examines impact of stirring the lees of barrel aging red wines. Cabernet Franc wine was settled overnight in tank after pressing and then racked into two identical neutral barrels. Barrel stirring occurred once malolactic fermentation completed and continued once every two weeks until wine was sampled in late April. No major differences were found in wine chemistry. Some lactic acid bacteria counts were higher, and Brettanomyces and Saccharomyces was higher in the stirred wines as well. No differences were apparent in phenolics, except for an increase in tannin in the stirred wine. For the triangle test, of 21 people who answered, 7 people chose the correct wine (33%), suggesting that the wines were not significantly different. In general, of those who correctly distinguished the wines, 3 had no preference, 2 preferred the stirred wine, and 1 preferred the no stirring wine. For the descriptive analysis, there were no strong trends for the descriptors used in this study. There was a very slight trend for the stirred wine to have lower Astringency. In the future, more studies should be performed with red wine lees stirring, perhaps with differing levels of lees in the wines as well.

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