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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Reverse Osmosis Trials (2014)

Reverse Osmosis was performed on Merlot, Malbec, and Petit Verdot wine in order to assess its effect on the chemical and sensory aspects of these wines.  Chemical parameters were not much affected by reverse osmosis, although color intensity was increased in RO wines.  Hue was also slightly increased, suggesting some oxidation from RO.  The Merlot and Malbec wines were found to be significantly different between treatments through triangle testing, but Petit Verdot showed no discernable difference.

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