It didn't take long to realize that my hope that Vines Wines would provide a forum for winemakers and viticulturists to discuss current industry trends and new scientific literature relevant to growing and making wine was in vain. The reality is that it is a journal that allows me to post tasting notes and to organize my head as I ponder different viticulture and winemaking issues. Discussion has turned to Tyler's Wine Gospel; for better but probably for worse. Therefore I decided that it would be nice for me to be able to use this site as my own personal reference to topics that I have investigated while trying to stay current with winemaking and viticulture trends. A summary of Rootstock information, Sulfur and wine , and others now provide - for me - a quick referral when I need to look something up. Let’s just hope I am able to stay current.
To these recent additions, I also added a page entitled Oak Opinions. Though currently quite slim, as we barreled down our last 2006 red wine lot this year, oak has been on my mind. I recently gained access to a French publication that focuses on oak: Journal Des Sciences et Techniques de la Tonnellerie . Now the French have a habit of 1) publishing their data only in French and 2)relaxing the definition of peer reviewed. While around 175 million people do speak French, a quick glance at the list of countries will not inspire thoughts of romantic enological getaways or bastions of vineyard science. One of these days the French will realize that - while beautiful - everyone should not have to learn their language. But I digress. More alarmingly, the lack of stringent requirements for the Materials and Methods section leads to - at least in the aforementioned journal - important information falling by the wayside. For example, in several articles I read in this BARREL focused journal, there was nary a mention of how many barrels were included in each treatment. However notice I said articles I READ. I don't speak French and that is the beauty of this Journal, despite other deficiencies, the articles are published in French and English (the French ones appear first, of course). Additionally, the noteworthy UC Davis Professor Vernon Singleton found the journal credible enough to contribute a review article in a Volume 6 2000 issue. Finally, the articles I have read (one of which I will get to shortly) often were focusing on principles and not necessarily examining amounts. That is, they observed trends that if true in one barrel, would likely prove true as a principle in most barrels - even though numbers might differ. One of the articles in question set off more self-congratulation regarding the erroneous and arrogant belief I have that most people just don't get barrel aging (as if I do in my young career!). This is something I have written about previously , but lacked a definitive paper to support my position. Then I was relying on one of the frequent rants of Professor Roger Boulton. Let me quote my intro: It is taken for granted that aging wine in oak not only imparts yummy complementing flavors to the wine, but also is an excellent way to slowly expose the wine to O2. Now, I do not doubt that the wine in oak is exposed to more O2 than the wine in a sealed stainless tank, but is it really true that the O2 is coming into contact with the wine through the staves? Before answering let me say that this issue is beyond taken for granted, what I am about to do is commit enological heresy. For most this discussion is useless because it is already settled. Not only that but in their minds there was nothing to ’settle’, it just is, a fact, a priori. Back to my answer: no. I think enological heresy is hyperbole. Certainly I am overstating the lack of understanding regarding how O2 gets into the wine. Nevertheless Gaseous exchange in wines stored in barrels (Volume 4, 1998 J. Sci. Tech Tonnellerie) clearly demonstrated that when there is a good seal between the bung and bung hole, a vacuum develops and oxygen slowly and continuously decreases despite a steady increase in the headspace volume. Now, they did look at %O2 as opposed to the gross amount, meaning that the decrease could have been due to the increase in overall volume, but it doesn't appear to be the case here. While the authors still maintain that O2 can get through the staves it seems to me that oxygen enters your barrel - assuming a good bung/bung hole fit - only when you remove the bung to top the wine to prevent too much oxygen exposure. Of course this begs the question, do we need to top as frequently as we do if very little air is moving into the barrel? Well, in theory, no. If the bungs are very tight and a vacuum typically forms, then it means the O2 in your headspace is steadily decreasing, so why top it? (The aforementioned study demonstrates this, though they did not let the experiment go long enough to conclusively show that O2 becomes zero; therefore I do have to allow for the possibility that O2 may be coming in another way. Perhaps as headspace is formed, drying of the top stave occurs, increasing the likelihood that 1) o2 can ingress through micro leaks and 2) the bung/bunghole seal is compromised. This has been noted before, generating the suggestion that bungs should be hammered and the barrels subsequently rolled to their side so the bung/bunghole seal is always in contact with wine). It's a little scary when I consider that sometimes I remove a bung at topping and notice there is NOT a vacuum. In other words some barrels are allowing O2 in, most likely through the bung hole. But maybe if it's good enough for Château Pétrus , its good enough for me. I recently learned that they hammer their silicon bungs in and perform zero topping. However they still rack every 2 months so the wine is exposed to plenty of O2.
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