O2 in Racking

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Feb 9, 2005
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Hey guys. Does anyone know if there is an adverse effect in having 02 reintroduced during racking? It seems that some 02 will be introduced. Is it better to keep as much out as you can or in the long run is the 02 forced out in the 2 fermentation without ill effect???

O@ is best avoided. It's more important with mead than beer because mead lives so long. If you have a CO2 tank, you can just shoot some CO2 in the container you're racking to, and you're set. We did that when bottling mead too.

If it's still fermenting, then you have no worries. The CO2 offgassing will replace any O2 in the fermenter. But if it's pretty much done and you're racking to a fermenter for aging or something, then it's best to purge with CO2, or at very least try to minimize any splashing.
The introduction of oxygen to any beer, mead, cider or wine after the yeast have completed the aerobic portion of their life cycle can cause oxidation and a stale, cardboard, winy,papery or sherry-like aromas and flavors. However, the chemical process takes time and most often is not noticable to the average drinker. I would recommend that you avoid splashing the beverage as you rack to a clean fermentor, bottle or keg. To paraphrase Charlie Papasian, "Relax, Don't worry, have a homebrewed mead".