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Deege
01-20-2005, 06:37 PM
I had a few questions about "feeding the fermentation"

If I add more honey to the fermentation, how do I calculate the final alcohol content? Using the initial SG won't work, because I've added more.

Is there a good method to adding more? Do I just pretend I'm making a very small batch, and then add the result?

The reason I ask is that many have said I added too little honey (27.5 lbs clover for 10 gal batch). Will it matter if I planned on adding fruit later? How about vanilla?

Thanks again!
Deege

Talon
01-21-2005, 09:37 AM
Using that much honey for a 10 gallon batch, I'd say you've got a starting gravity of 1.110. Not low, but will give you a dry mead if you use any wine yeasts. If you don't go over 36lbs of honey for your 10 gallon batch, you'll be okay as that will give you close to a 1.140 starting gravity and with a yeast that has 14% alcohol tollerance, will bring it down to about 1.020-ish...

To give you a base line, in a 5 gallon batch, your specific gravity will go up by ~0.008 points for each pound of honey you add. For a 10 gallon batch, it should be about 0.004. So, my suggestion is to figure out what you want your alcohol content to be, and do the math from there.

Talon.

CosmicCharlie
01-21-2005, 04:06 PM
I'll throw my 2 cents in: Ive done that once, and I boiled some water to get the 02 out, let it cool, added and mixed the honey, then add to the fermenter. You can still do it if you want even if you're adding fruit or vanilla - the one concern with fruit is that it will add volume, so if you 'feed the must' you may lose some when you add the fruit.

Deege
01-21-2005, 11:49 PM
I'll throw my 2 cents in: Ive done that once, and I boiled some water to get the 02 out,

Thanks CosmicCharlie! Why do you want to let the O2 out? I thought the yeast needed that. Is it bad at later stages?

DJ

jab
01-22-2005, 03:53 AM
Yeah it's pretty much considered bad. Basically the yeast need oxygen during their first stage which is reproduction. Once they start converting sugars into alcohol (fermentation) then the need for O2 is gone. Too much O2 after the reproduction stage will probably give you off flavors.

Pewter_of_Deodar
01-22-2005, 02:10 PM
I haven't lost a batch of mead to oxidation yet... *knocks on wood*

However, I can tell you that oxidation will make a good raspberry cordial taste like raspberry cough syrup...

Oskaar
01-22-2005, 04:50 PM
I've only lost one batch to oxydation and that was several years ago. It was a joint effort with one of my buddies, and we took the stuff to his house to make it. I let him keep the carboy there, which was an error on my part.

After about four months I went over and noticed that the level was down a bit, but the same label was on the batch so it hadn't been racked. I asked my buddy if he could lend me his wine thief (which is what I was ASS-uming he was using) and he looked at me with a blank stare. Not good. We went out to the garage to check it out and the airlock wasn't set or sealed into the mouth of the vessel. Evidently he had been pulling the airlock off and pouring mead out to taste it, and then just placing the airlock back in the mouth. I took a whiff and confirmed that it was gone. That really re-affirmed that I shouldn't let my equipment go wandering to other peoples houses.

Sad day in meadville when we poured that batch out.

Oskaar

Pewter_of_Deodar
01-23-2005, 03:38 PM
Oskaar,

I have heard that a small amount of oxidation (and the resulting bad taste) will "age out" as a result of ther aging processes taking place. Any thoughts?

Pewter

Oskaar
01-23-2005, 06:59 PM
Yup, a small amount of oxidation will age out with no ill effects. In fact, the oxidation you get from aging your wine or mead or even beer in a barrel has a wonderful effect on the flavor because it is a very gradual oxidation that is tempered with the infusion of the oak flavor. I inherited three french oak barrels from a winemaker friend who passed away recently and I think I am going to try a couple of larger batches of mead in them. He used them for his Syrah's and Cabernets. I'll have to rehydrate them and check for leaks and such to make sure they're still viable. From outside appearances they look to be ok. Two were pretty well used, the third is nearly new and very fresh. He also left me a wooden basket grape press so I'm going to pick some grapes this year instead of just getting juice like I have for the past several years.

But, back to the point. This batch my buddy was nipping drinks from had actually started a mold growing on the top. I snuck a tube in toward the bottom but the whole batch was moussy tasting so we dumped it.

Cheers,

Oskaar