Unending melomel batches

[jayich]

I have a 7.5 gal berry melomel in secondary(see OB melomel brewlog) in which I am thinking of splitting into two batches by racking off 3 to 5 gal for aging on oak, while adding more honey and berries and a 96 oz can of either elderberry puree or black currant puree to make another aprroximately 5 gallon melomel, which would be allowed to ferment completely. What are the risks in doing this? How many times can it be done before the yeast gets stressed out or mutates? I know there are many potential problems, including the need of additional nutrients and O2. I used this technique to split my last melomel batch and they seem to be aging OK on oak and they taste good so far. I would appreciate any comments.

 

[fatbloke]

If you have ways of measuring the unmeasurable, then fine.

There's no telling when the yeast will die off. The theory is that as long as it's fed properly, with the appropriate amounts of nutrient, O2 etc, then you should be able to keep it going forever.

But....... that's not really practical.

You have to get any yeast out before alcohol toxicity builds up enough to start killing it off. You have to know the ideal levels of nutrient/O2 to keep it multiplying, and still munching it's way through the sugars in the honey/fruit to produce the alcohol - while still being able to keep some going for the next, follow on batch......

So it might be better to just either take some must from an existing ferment and then chill it down and keep it refridgerated to act as a starter for the next batch, or if you want to change yeast type, just make a decent sized starter and use some of that for fermenting and then retain some as a continual starter for follow on batches with the newer yeast type........

regards

fatbloke

 

[jayich]

Thanks for the help fatbloke. What you say makes sense. I now have a OB honey melomel(see my brewlog) in which I have added successive amounts of honey and berries and the yeast so far has increased fermentation after each addition- so I think it is probably ok. My plan is to let rack off 5 gal into a carboy with oak, and to the remaining 2.5 gallons, I will add 1.5 gal of more fermentables(honey and 96oz can of black currant puree) to make a second 4 gal batch. I will let you know how both turn out. I think continuing the experiment beyond this point would run into multiple potential problems- as you pointed out.