Friday, August 31, 2007

When Wine is Not Vinegar....



I have been making vinegar for some years now. Part bottles of red wine that have sat around for a few days and I do not want to consume in their oxidized condition find their way into my trusty little vinegar barrel. I have to top it up regularly because like all oak barrels and especially in smaller ones, there is a significant amount of evaporation. I let it sit for up to 9 to 10 months and then bottle the contents of the barrel, making sure I leave enough to start my next batch with the remaining "mother". Rummaging through some of my old files I ran across this certificate from the Vinegar Man. Check it out if you are into making vinegar or are contemplating to start doing so.
The reason I am getting carried away with all this vinegar stuff is because of this "just in" bit of news about this new machine.
Sounds good but only one small problem.
This machine looks for acetic acid. Acetic acid is produced by Acetobacter aceti which is a gram negative aerobic bacterium.
When air leaks past a faulty cork and if the Acetobacter is present, the ethanol is oxidized into acetic acid. And there in lies the problem. Not all wine contains the Acetobacter bacteria and therefor not all oxidized wine automatically becomes vinegar. Good winery practice by restricting exposure to oxygen and making sure the must is properly sulphited, will all but eliminate the problem. Having said all that it has recently come to light that the Acetic acid bacteria can remain viable in wine for years even under anaerobic conditions. Take a moment and read how. All the more reason for careful winery practices. In the meantime I don't think I will be rushing in to spend fifty bucks to have my wines analyzed. I will continue to store my wines properly and whatever is left over after I open a bottle and not drinking it all, will end up becoming some awesome vinegar because that little old barrel of mine has plenty of Acetic acids bugs waiting for it.

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