Adding apple juice to the yeast cake, then do it again, and again...

[z-bob]

After I bottle my cider, I add more juice (and a cup of sugar and a teaspoon of yeast nutrient) to the carboy to start a new batch. Is there any problem with doing this over and over? My theory is the active yeast will use the dead yeast for nutrients; autolysis would only be a problem if there is no active yeast to consume the byproducts. Is this right? Even if it is, am I disrupting this by adding the small dose of Fermax? I'm on my 3rd batch from the original yeast pitch right now, and the amount of lees doesn't really seem to be increasing. Just wondering if I'm pressing my luck. I'm bottling a few days after the cider looks clear. These carboys are translucent instead of clear so it's kind of a guess, but in any case it doesn't stay on the lees for very long. Lag time after adding the new juice is longer than you'd expect, a couple of days, then it is very active.

I suppose I could hedge my bets by using D-47 yeast; I think that's the one where time spent on the lees actually enhances wine. What I am using right now is Red Star Cote des Blanc and inexpensive apple juice from Aldi, Costco, or Hy-Vee. (the Aldi and Hy-Vee juice are made from concentrate, the Costco juice is not)

 

[madscientist451]

I only make cider in the fall when apples are available and I usually make 3 versions, with Early apples, mid season apples and late ripening apples. So I'm a lazy brewer and I just rack the cider off the yeast and toss in the next batch. I use Cider house select yeast and after about 3 batches I either have enough cider or I'm burned out on the gathering apples, grinding and pressing so the yeast gets dumped. So your results may vary depending on several factors, but I've been using this method for years and all the hard cider always gets consumed, so it works for me.

 

[CKuhns]

Dead yeast and the trub that settles out with live or viable yeast can over time cause off flavors. If using your yeast cake more than 2 or 3 times and or if you let it sit for a week or two could cause some issues with flavor.

Healthy yeast are easily washed and seperated from the dead or other solids. To do so add a equal volume of good quality water to your yeast cake. Shake it for a minute or two. Set it aside and let it settle for a few hours. At this point you should see three distinct layers.

Clear or opaque - Mostly water.
Light tan - Healthy Yeast
Dark tan or brown - Dead yeast and other solids

Slowly decant the water and discard or use to water your plants. Then do the same to the tan layer and save that for your next ferment. Discard the dead yeast.

 

[z-bob]

I know how to harvest yeast, I do that with beer yeasts. Was just wondering about wine yeast and a fast turnover, since the lees don't seem to be building up. After 3 or 4 cycles, I will just dump them on the compost pile and spring for a new 79¢ packet of yeast, it's really cheap insurance and I have lots of packets in the fridge.

 

[teddyearp]

Cool. I came here to ask this very question and here it is. Answered. I think I'll just do about 2-3 reuses max as for me the whole thing is being lazy like madscientist. Just to confirm, it does start to change flavor even though I don't waste time. I siphon off to bottling bottle, pour some more juice on it, finish bottling, then add sugar and nutrient right away.