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gavinonymous
11-14-2008, 08:09 PM
How would bentonite best be used in a conical fermenter? Would it be best to add early, sometime in the middle of fermentation, or late (1 week prior to bottling)

Medsen Fey
11-14-2008, 08:34 PM
It may take much longer than 1 week for it to settle and clear, so IF you need it, adding it sometime after fermentation completes but more than a week before bottling is probably best (unless you plan to filter it). Generally I find that I don't need fining agents - time does the work.

And lest I forget -


Welcome to the new and improved* GotMead? gavinonymous!


* and green too :)

gavinonymous
11-15-2008, 11:01 AM
Thanks for the welcome, and your reply :)


I'm not filtering at the moment, but I've looked at the enolmatic (seems a bit flimsy though) and tried the plate filter - which I wouldn't recommend or do again.

I'm making dry traditional meads (using better bottles with racking adaptor) that finish fermenting very quickly, bentonite worked well enough to give a medium clear stable product that could be bottled at 3 weeks (as short as 2 even)

I tried using bentonite after racking with good success, going against the advice of 2 local wine kit suppliers that told me to add it up front. This time I decided to see what would happen if I added it up front (it's only been 2 weeks) and I can't think of a good reason to rack it. If I rack it, will I lose the effect of the bentonite? Do I need to add more?

When I added it up front there was a 'conveyer' effect - where particles of bentonite float up and down for a few days early on, and then settle out (I don't know if this is why I was advised to use it early.)

I'm planning to scale up to the 42 gallon conical fermenter shortly, I figure that I can dump the lees early on, and stir in the bentonite slurry after fermentation slows enough - but I worried how much it would expose the brew to oxygen? I'll have to open the lid to swirl it in. Maybe I'm more worried about exposure to oxygen than I should be. It seems to help a bit even, so I've read, and experienced.

I'm not sure if I'll lose the effect of bentonite added up front after dumping lees because I'm not really sure how bentonite works. Does it work best during primary or secondary fermentation - or does it even matter, so long as you add it and give enough time to be exposed to your mead to clear before bottling(and/or bulk aging)?

Thanks again for your replies. This forum has been a great help already.:)

Medsen Fey
11-15-2008, 11:58 AM
There are several questions here - I'll take a stab at some of them.



I tried using bentonite after racking with good success, going against the advice of 2 local wine kit suppliers that told me to add it up front. This time I decided to see what would happen if I added it up front (it's only been 2 weeks) and I can't think of a good reason to rack it. If I rack it, will I lose the effect of the bentonite? Do I need to add more?

Maybe I'm not understanding but if you are using a conical you shouldn't need to rack. For folk using carboys, they can continue to swirl the container to resuspend the bentonite a few times to make sure it binds everything possible, and then wait at least 24 hours for the heavy stuff to settle out before racking (I usually wait until it is a clear as it is going to get before racking.

After racking there may still be some residual bentonite in the solution, especially if it is not clear. It will continue to settle after racking. If you keep adding bentonite it will strip the color and flavor from your mead. In wine making it is generally recommended not to exceed about 0.5 g/L.


When I added it up front there was a 'conveyer' effect - where particles of bentonite float up and down for a few days early on, and then settle out (I don't know if this is why I was advised to use it early.)
Probably. In very clear musts, bentonite may improve fermentation kinetics, but in wine, it also increase H2S production. I'm not sure if it occurs the same way in mead, but keep alert for the possibility.

A big negative is that using it during fermentation in wine making means that you cannot age the wine on the lees as the bentonite treated lees will produce off-aromas. Again, I cannot tell you for sure if the same thing will occur with mead, but if anyone has tried aging on bentonite fermented lees please chime in.


but I worried how much it would expose the brew to oxygen? I'll have to open the lid to swirl it in. Maybe I'm more worried about exposure to oxygen than I should be.
After fermentation completes, there is usually enough dissolved CO2 to chase air out of containers so that opening them to gently mix in fining agents does not cause oxidation. But clearly, after about the half-way point of fermentation, you want to protect your mead from oxygen.


I'm not sure if I'll lose the effect of bentonite added up front after dumping lees because I'm not really sure how bentonite works. Does it work best during primary or secondary fermentation - or does it even matter, so long as you add it and give enough time to be exposed to your mead to clear before bottling(and/or bulk aging)?

It can work in primary or secondary. The advantage of using it at the start of fermentation, in addition to the kinetic improvement is that it may require less total bentonite.

The Improved Wine making (http://www.brsquared.org/wine/Articles/fining.htm) site has a nice article on fining agents - it is worth a read and will explain more about bentonite and how it works. Keep in mind that bentonite will not clear every mead, and you may need other agents at times.

After all this, again I would say that with fining agents you may sacrifice some color, flavor and aroma. I do not like to do this. Most meads will become crystal clear given enough time to settle which may be months. I don't even think about fining anything until it has sat for at least 6-9 months. You might want to try a batch without bentonite to see what happens. I'll give you another tidbit to consider - a little bit of oak may speed clearing as well as improving the flavor of traditional meads.

In mead making the most important ingredient (and the most difficult to find) is patience.

Good Mazing!
Medsen the loquacious

gavinonymous
11-15-2008, 12:57 PM
Sorry for the confusion - I'm currently using clear carboys (better bottle with racking adapter) in my tests to see the difference adding bentonite (I'm using about 0.4g/L) before vs. after racking to get a good idea of what's going on in my meads. I'm only planning now to scale up to a conical fermenter, and wondered how that might affect my decision of when to add it.

So far I haven't noticed any off or lost flavours with the early addition of bentonite. I'm reading in the link that it can remove phenolic compounds when used to fine juice for wine, which maybe helps explain why the bentonite batches seem to taste better than my non bentonite batches notably cutting down on phenolic taste.

Still it reads that most recommend using it when fermentation is complete. With a conical fermenter I might decide to compromise and add bentonite after some lees removal.
.

A big negative is that using it during fermentation in wine making means that you cannot age the wine on the lees as the bentonite treated lees will produce off-aromas. Again, I cannot tell you for sure if the same thing will occur with mead, but if anyone has tried aging on bentonite fermented lees please chime in.

not sure if I understand why bentonite gives off aromas, so far I haven't noticed it - but I'm not aging on the lees for very long. The first test batch I used bentonite after racking in a carboy was clear enough to bottle after 3 weeks. It's now aging in bottles, but keeps disappearing :( The mead has so many subtle flavours and different notes going on from the honey.. i think I got licorice even - I had to aerate it a fair bit to be fair. I should have made much more!