I have been making red wine from grapes for several years. I have been doing the aging in 5 gallon glass carboys with oak sticks. I recently obtained an oak barrel which I am going to use to do some of the aging in. This is where the alternative theory part begins. When wine is stored in oak barrels the wine slowly evaporates through the oak, which results in an air space in the oak barrel. It is recommended that you 'top off' the barrel periodically. Anyone who makes wine (or beer) knows that oxygen is very bad for this process. It is true that a small amount of oxygen is beneficial to the taste of wine (that is why for unblended wines it is good to let them 'breath'). But if you have a bottle of wine that is left out over night (even if the cork is replaced) the flavor degrades. So anyway from what I have read the going theory is that air space in a barrel is not big enough to cause a degregration of the flavor. My alternative theory is that there really isn't any oxygen in the air space of the barrel. I think that as the wine diffuses out through the oak and the air diffuses in through the oak the wine molecules oxidize and consumes the oxygen so that essentially there is only nitrogen that makes into the oak air space. Not sure how to test this since even if oxygen made it into the air space it would be oxidized by the wine in the barrel so there would not be any oxygen in the air space in either case. What do you think? Am I missing something obvious or subtle?
caveat: I know next to nothing about making wine. However, after years of practice, I have become somewhat adept at consuming it. remember the "go go girls"? I do know a bit about wood. what kind of oak? red or white or black? new or used cask? Anyway When bottled send me one, and Ill happily opine as to it's quality.
Golly it sounds complicated. I suppose one aspect is what chemicals react with very low levels of oxygen as it diffuses in. Presumably one want the ethanol not to turn to acetaldehyde, as that I imagine would rapidly oxidise further to acetic acid. However controlled oxidation of tannins might be beneficial, causing precipitation and removing some of the harshness. I do not know the relative reactivity of these species but I presume tannins react faster than ethanol, since tannic wines keep longest - of the reds, that is. Long lived whites, e.g. Sauternes (I drank my last Ch. Guiraud 1983 only 5 years ago and it was lovely) must presumably rely on a different antioxidant system. I see on the web you can get oxygen sensors that can detect in the ppm range, i.e. in almost anoxic conditions. So you could test the ullage air space.
Exactly. Grape juice 'wants' to turn to wine (wild yeast will do it) and wine 'wants' to turn to vinegar. The first wine I made was a crappy white wine from Cayuga grapes. The wine was very unimpressive - but I make it into a really wonderful vinegar now. The chemistry of wines is really quite complicated with all of the different esters, phenols, etc., etc. adding (or detracting) to the aroma and taste. I find it interesting that it only takes about 2 weeks to make a Cabernet Sauvignon, but it takes at least an additional 18 months to make a decent Cab. I'll check it out thanks. By the way it looks like you drink much better wine than me!
Typically the barrel wood is white oak. My son got me a brand new 2.5 gallon white oak barrel - which is absurdly expensive. I am conditioning it now to put in part of my 2015 batch of cabernet franc.
Question 1 Is there a difference in flavor if used a new barrel or a used barrel. In new barrels air might be adsorbed on the surface 2 What kind of washing have the barrel experienced 3 What surface roughness the barrels have between one and the other? When the barrel is open aor gets attached to the wall of the barrels. later in time desorbed attacks the flavor There might be other questions
The Sauternes is not something I drink every day. But having a French wife encourages a bit of ceremony at the table from time to time. Foie gras and Sauternes is one of those agreeable things that is worth funding, at least once or twice a year. Cab Sauvignon is potentially very tannic I think - the main grape of the Medoc, where decent wine can only be drunk at 5-10 years. Anything less and it is pretty rough. I've noticed that Bx tastes rather rough and bitter until you leave it long enough to throw a significant deposit. There seems to be a period in between, when the wine is a bit cloudy, as if the precipitate of tannins is forming but the particle size has not yet got big enough for it to settle. The 2005 and 2006 Medoc are mostly quite nice now, though 2006 was ready earlier than 2005. But all this is going on in the bottle, not in the barrel. I suppose the corks breathe a bit too. (I have read that Mouton Rothschild has a 20yr+ trial going on with plastic closures, just to see what happens. Of course their stuff - which I cannot dream of ever affording - can last over 40 years.....)
Cabernet Franc is rather delicious even young - raspberries - at least in the Loire (Chinon, Bourgueil). In hot years it can be like Bx. But I've learned that in the New World these grapes can taste utterly different. St Emilion (Bx right bank) is Cab Fr + Merlot and these seem to take only half the time of Medoc to be ready to drink. But I'm not very expert on St Em. (the wife was raised on Medoc, cepage of which is typically Cab Sauv+> Cab Fr+> Merlot+ > sometimes a touch of Petit Verdot - and I have to say I have had no serious objections to that choice.)
I should have noted that wine wants to turn into vinegar with the help of different species of acetic acid bacteria.
Different woods have different antioxidant levels with chestnut being just about the highest followed closely by some of the oaks. Then we look at the phenols, eg; ellagic and gallic acid etc.... Also, different woods will alter the flavor of the wine. I'e never read about using catalpa(also known as chinese coffin wood) for aging barrels, but when carving or sanding it has a rather spicy peppery flavor. What are you doing to condition the barrel? good luck hope to read more about the final outcome.
Very simple. All you need to do is to keep it filled with water for a week or 2 so the wood absorbs water and expands. An interesting thing happened here where I live. Somebody bought a defunct winery near here and found some huge wine barrels, like 10 ft in diameter on the long axis, in the cellar. He put out some 'feelers' on what they were worth and it turns out they were worth more than what he paid for the winery! The guy made money on the purchase of the winery. I will let you know - I have to be very careful not to 'over oak' the wine since this is the first batch in a new barrel.
Are you saying you think it is only the evaporating wine soaked into the barrel that oxidizes? Maybe, but that sounds like an argument for keeping it full, not for "doesn't matter". Unless the wicking action is substantial, the upper part of the barrel will dry out, which not only eliminates the absorption from evaporating wine, but also makes the barrel more porous, allowing air in faster. The air above the wine in the barrel wouldn't have zero oxygen (implying none to absorb into the wine), it would have *almost* zero oxygen, because of exactly the problem you describe: it is being absorbed into the wine inside the barrel.
Wine probable would have similar problem as beer cans . Even the walls of a beer can are of metal , but there are other problem that the winemaker does not take into account. That is why the wine maker have introduced SO2 or bisulfite.
What would happen to your wine if you let them grow ? and what kind of bacteria will grow ? Don't you think is an antioxidant to prevent oxygen oxidation and to convert your alcohol to aldehyde abd later to vinegar ?
When fermentation is done with crushed grapes the fermentation is 'open', which means the vat of ferminting grapes and juice (refered to as must) is open to the atmosphere. In the begining of the fermintation before much alcohol is produced all kinds of bacteria can enter the must and cause off flavors, so it is vital to sulfite the must. After the alcohol level increases most bacteria cannot live in the wine. One type of bacteria that can live in there is the kind that produces vinegar so you really do not want that kind to get into the wine. After the primary fermentation some people purposely decrease the sulfite level to encourage the growth of certain types of bacteria to grow in the wine in a process called malolactic fermintation. These bacteria metabolize malic acid to lactic acid which has a less bitter taste and adds a 'buttery' flavor to the wine. I do not do this with my wines. Not sure what you are tying to say. If you are asking if the sulfites are used as an antioxidant, the answer is no, sulfites are only for protection from bacterial growth.
I looked this up in Jancis Robinson's Wine Encyclopaedia. She (or whoever wrote the entry) says metabisulphite is often added to the crushed grapes to stop various enzymes from oxidising the juice. So that suggests a second role besides that of disinfecting from acetobacter etc.
Hmmmm, most my knowledge is from 'how to make wine' books and from the vineyards were I get the grapes. I guess I am light on the actually theory or Jancis is a liar. It is probably the former and not the latter....
Sulfites are antioxidants you like or not . I don't know about making wine but I believe is ab aerobic fermentation and if so, there is a large amount of CO2 produced and that is vented ( Champagne bubbles ) and that is saying oxidation is taking place . If you want to stop oxidation , there are some natural antioxidants in the mush. But if you have openings were oxygen can penetrate your mush will continues been oxidized , but to stop it you add bisulfite or purge the vessel with SO2.
As I said above I was incorrect about the sulfites not helping to prevent oxidation. Fermentation of sugar to ethanol by yeast is an anerobic process. So ideally there is no or little oxygen to be oxidized. The CO2 (and alcohol) is not produced from oxygen it is produced from the anerobic fermintation of sugar by the yeast.
