Cellar News

Upside Down Fermenting? | CellarBlog

I heard about this while I was in Bordeaux and thought it was a neat idea, but I didn’t have all of the details at the time. The image above is the <

> fermenter, created by the team at Tonnellerie Radoux, one of the world’s best-known cooperages. The idea behind the <> fermenter is that it will improve the color and tannins of a wine by allowing winemakers to extract the wine in a more gentle fashion than traditional punchdown methods.

The <> fermenter takes advantage of gravity and a conical shape, that is very much in fashion with fermenters, to improve the quality of the wine.  Of course, all of this is in theory — fortunately Jean-Luc Thunevin put it to the test with the 2015, vintage.

Here is how the test worked:

The first experiment with this new vinification tool was carried out during the 2015 grape harvest. A cabernet franc from a 25-year-old vineyard with chalky soil was chosen for this test. The best bunches on the vine were handpicked and sorted.

Two batches, harvested the same day and on the same section of the vineyard were isolated and fermented using whole grapes, one in the « Upside-down » fermenter, the other in a 400 liter barrel with an open head.The vinification protocol was identical for both batches: cold pre-fermentation maceration over 8 days with 2 turns of the « Upside-down » fermenter and 2 daily punch-down operations for the barrel.   Then, after the beginning of fermentation, 5 half turns a day over 5 days for the « upside-down » fermenter and 6 punch-down operations for the barrel. Finally, during extended maceration (between 2 weeks for the barrel and 3 weeks for the « Upside-down » fermenter) 4 and a half turns and 2 and a half turns were made every day with equivalent stirring for the barrel. After the drawing off and gentle pressing, the two batches were transferred, along with the juice solids, into new barrels.

The end result is that the wine aged in the <

> fermenter showed more color and more intensity. Of course, that could just be bias of the tasters, so they did a second test:

The tasting results are confirmed by laboratory analyses, with evidence of a better average colorimetric index with the batch prepared in the « Upside-down » fermenter.  The more intense color indicates that the extracted anthocyanins were better or more quickly stabilized by the system used with the « Upside-down » fermenter.  In addition, the higher level of anthocyanins combined with the tannins reduces the sensation of astringency and renders the tannins more silky on the palate.

 Overall, I think it is an interesting technology and, at first blush, it seems to have worked.  Of course, 2015 in Bordeaux was a near perfect vintage. The real test will come with how it performs on a less than stellar vintage.