To Rack before Bentonite or not?

The experts I learned from say that the object is to bring _all_ the wine into contact with _all_ the fining material, as thoroughly and as quickly as possible. That means slow addition while vigorously stirring, but not so much as to whip a lot of air into the wine.

Tom S

Art,

Along with Tom's advice I would recommend this stirrer.

You attach it to a drill and put it in the carboy. You make sure after the thing is inserted that the wine is as high in the carboy neck without overflowing when you start the drill. It'll take a little practice to see what I mean BUT this thing does a great job of mixing WITHOUT exposing the wine to alot of oxygen if done gently and slowly. Only the swirling in the neck will be exposed. Alternatively the less you top up the more oxygen will be introduced and the more gas that can be driven out. I use this ALL THE TIME and is worth the investment. BTW, if you decide to get it, wait until it arrives to add the bentonite. If you refrigerate the bentonite ( covered of course ) it should stay for weeks

Bob.

It appears then that letting finings "fall through" is not good practice.

I do have one of those stirrers. I have used it with a reversing drill such that if the top layer begins to get too turbulent I reverse the drill. This seems to prevent voritices and such at the top while mixing the internal parts well.

Thank both you very much.

Art Schubert Traverse City, Michigan

If you prepare the bentonite in boiling water and pour it hot into a jug and seal it airtight, it'll keep _forever_ at room temperature.

Tom S

You have already gotten good advice.

I would add that if you use that stirrer and you have a lot of disolved CO2 in the wine it will let you know quickly if you spin it too fast. It looks like a volcano...

I usually pull out a liter or so when I do anything that involves agitating the wine, if it does not foam up you can add it back in while stirring.

Fining trials would help you avoid stripping out any flavor, you may want to consider pulling out 3 samples and adding the expected dose in

1/3 increments to see which is actually needed. I found I did not need as much bentonite as I typically used by doing this. You can make a hot box with a small light bulb and box if you want to do the temperature stability tests, but I haven't done those for a long time. If it clears, I consider it good to go.

For whatever reason my Gewurz always needs more that the others. I make all of the wines you are making.

I usually dont fine Pinot Noir, time does a great job all on its' own. When I do, it's usually hot mix sparkleloid.

Joe

Thanks, Joe.

Last night I got two of 6 carboys done. I didn't top up before stirring as much as Bob mentioned. No erruptions. Perhaps sitting for

3 months let most of the CO2 out anyway.

Interesting about the Gewurtz. It is the cloudiest of the lot

Thanks again,

art

Art Schubert Traverse City, Michigan

Interesting. I always thought it would settle out over time.

Would you sulfite it once you start using some of it? Or does the refrigeration keep bacteria from becoming a problem?

Art Schubert Traverse City, Michigan

It does - but it's easily resuspended by shaking vigorously. Bentonite _never_ dissolves; it's clay.

As I mentioned (or implied), I don't refrigerate bentonite. Sulfiting an opened container isn't a bad idea though. You'd also want to bring the pH down to ~3 or so with tartaric.

Tom S

I am always somewhat confused about this part. How long does it take for the fining agents to settle and the wine in the small bottles to become clear? And doesn't this require all fining agents to be put in together in 1 trial? I usually do bentonite first and then other fining(s) after if needed. But if the wine needs something else, it won't become clear just by adding bentonite, so how would the bench trial for just bentonite work?

This is the one part of winemaking where I'm still scratching my head... Any advice appreciated.

Thx,

Pp

I would rack it before you add the bentonite or you will mix all the particules from the bottom of the carboy to your wine. The bentonite will catch those particules. I do not know why you would not rack your wine if it is only for laziness and then you will be in the same category as me. ;) I do not stir my wine but sometime there is too much Co2. It is a good way to get rid of it and you can add some acid ascorbic or vitamin C to prevent the oxydation after you racked it then add your bentonite.

Bisulfite with vitamin C is what I use and they both prevent the oxidation. While racking the oxydation is negligible and should not worry you. What is bad is a long exposure to the air. For example, take an apple and cut it in half. After some time it will change color but it will not be right after you cut it. It still talkes some times. You should rack your wine even if I often do not do it after the two initial racking. Well I am lazy. ;)

A limited stirring at the top will obviously mix some particules from the bottom and I would not do it. I bought the super siphon more for curiosity and when I used it, it mixed the particules from the bottom. Also for the bentonite to be mix properly, you do not have to stir too much. If I would mix a lot, it would be to get rid of the Co2 .

We are all picky or most of us. So far I would advice you to rack your wine and for my part I do not put fining agent. I do not know how hot or cold where the wine is but after 80 days only you know if it needs a fining agent.

I think I just saw my nick . ;)

Pin

I would say less efficient. You can gently stir at the top as you suggested but still I would rack. If I was fining my wine and because I hate the racking, this is what I would do but not after 80 days. After 80 days anyway in a cool place the wine will at its best for another and last racking without any fining agent.

Pin

This is a contentious issue. Although ascorbic acid is ostensibly an anti-oxidant, my reading indicates that it may actually _promote_ oxidation.

I confess that I do not understand the chemistry behind that assertion, but I would be remiss in not at least mentioning the possibility.

Ascorbic acid is certainly useful in certain problem cases, where the wine has gone from a mere H2S or mercaptan problem (which is easily addressed by aeration or copper fining) to di-mercaptan (which is a lot harder to treat, and requires ascorbic acid, copper and activated charcoal).

That said, I see no good reason to add ascorbic acid _and_ sulfite to a healthy wine. Sulfite alone is sufficient. Less is more.

Tom S

I want a link.

Pin

Here is what I do.

I make my bentonite as a ~5% solution and hydrate it normally. I use about 1 ounce bentonite to 16 ounces of boiling tap water; I hit that with a mixer. Next day, I stir it up then add it to (3) 375 ml bottles of the wine under test with a syringe. I make sure it's really well incorporated by shaking if necesary. The ratios of hydrated bentonite are about 40 to 1, 80 to 1 and 160 to 1. (about 10, 5 and 2.5 ml per

375 ml bottle.)

By the next day you can usually tell if the 'lightest' sample is clearing, but they all clear somewhat. The less bentonite you use, the fluffier the lees will be, so don't go by the volume of the lees. Check out the top strata of the wine and compare each. Some use a flashight to see if the beam is visible as it passes through the wine, comparing each at the same level ensures you don't miss anything.

I usually wait around a week to make the final decision. If you are going to counterfine, you could add that then. It can only help, but I don't coounterfine too often so really can't say.

The more correct way to go is to now rack and heat the sample to ensure protein stability, but I never do that.

There are two simple methods suggested, heat the sample to 90C for 1 hour and chill or heat it to 50C for one or two days and chill. Now check for precipitate. My wines will never be exposed to anything near that, so I'm not sure I care to risk stripping more flavor out just to ensure a fine dusting of sediment does not occur in 'trunk stock'. I'm not saying it is unnecessary, just that empirically I have gotten away without doing this test for a long time. If I were selling the wine I would approach things nmore cautiously, but there are also 3 other more elaborate tests for protein stability.

I am usually using central valley fruit and think it's overcropped to begin with so I want to keep as much flavor as possible, I always err on the side of doing less unless there is a really good reason to do more.

I'm not suggesting this is the best procedure, others may have better ideas. It's just what I do. I only fine whites and meads, I rarely fine reds anymore. My reds are bulk aged for about a year and clear well without help.

Joe

It turns out that my trials showed that even with a very light bentonite (0.12 g / liter of wine = Tom S's 1 lb/1000 gal) there was some loss of flavor. I did the heat test and got no precipitate. So I think I'll leave off the bentonite this time.

Tom often comments on the flavor improvement found with bentonite but I couldn't find it. Of course I am new at this so my taster is not well calibrated yet.

And I am working with grapes that here in Michigan we must push to the very end to get to ripen all. This year the Pinot Noir came in at only about 20-21 brix. We had a low sun Summer and they did not get to ripening until late September (which was warm).

You folks have been most infomative on this. Thanks again.

Art Schubert Traverse City, Michigan