Stopped fermenting?

[scurry64]

So 2 nights ago I made a starter by dissolving yeast nutrient in some warm water, adding a packet of yeast, and putting it into 1/4 of a gallon of the wine that has the issue. It foamed some and then I added it back into the fermenter the following morning, this morning I checked on it and it didnt effect the batch. Should I try something else or put the fermenter into a sink of hot water? Somebody mentioned that to me. But the temp of the wine has been staying around 70° and the instructions on the base says to stay between 68-72. I started this batch on the 19th of mayl

That's not really an effective starter. I think you already have enough yeast in your must to do the job, so you don't need to add anymore. Stir the must twice a day and add a pinch of yeast nutrient once a day. You'll get there.

 

[BernardSmith]

But Allison, you basically pitched the yeast into the problem batch. If the problem batch has a systemic problem then for all intents and purposes you drowned the fresh yeast in the same problem. The idea of creating a starter and then simply diluting the problem by adding a little of it to the same volume of the fresh starter is that should there be a systemic problem in the stalled batch the starter will neutralize it.

 

[Allison Gray]

Should I retry the starter then with the yeast nutrient and juice or water then? And adding a pinch of yeast nutrient a day(

 

[BernardSmith]

Just a thought experiment here: Let's say that there was something in the must that created a systemic problem - let's say, for example, the concentration of sugar caused osmotic shock in the yeast or the pH was too low (the must too acidic) or let's say that the fruit itself produced sorbates which cripple the yeast. The minute you add yeast to those problems you can kiss that yeast goodbye. Osmotic shock will affect the new yeast, too much acidity will affect the new yeast and a relatively high concentration of sorbates will cripple any new yeast too. The idea of adding a small percentage of the problem batch to a fresh starter is that you are diluting any systemic problem. The concentration of sugar (if high enough to cause osmotic shock) is halved, the pH (if too low is raised) and if the fruit had produced any quantity of sorbates then that quantity would immediately have been halved. OK.
What to do now? My approach would be to try to figure out why your batch has stalled.. That, or create a starter (don't use the problem batch) and when that starter is very active (you are encouraging the yeast to reproduce with a starter and not make wine) then you add more volume to this starter from the problem batch. OR .. you could simply bottle the problem batch and Murphy's Law will apply and the batch will immediately spontaneously start to ferment again (or it will wait for you to go away for a few weeks on vacation and then restart.

 

[scurry64]

Should I retry the starter then with the yeast nutrient and juice or water then? And adding a pinch of yeast nutrient a day(

Start with 4 oz of apple juice or white grape juice, add 1/2 tsp sugar and a pinch of yeast nutrient. Stir to dissolve the sugar. Add a pack of yeast. After 2 hours add 2 oz. of apple/ white grape juice, 1/4 tsp sugar and a punch of yeast nutrient. Stir to dissolve. Repeat this process every 2 hours, except instead of adding juice, add your must. Keep the container covered with a paper towel. Shake it frequently to add oxygen. The amount of yeast will double every 4 hours. After 24 hours you'll have enough yeast to ferment 40 gallons of wine. This is the procedure developed by Jack keller that I directed you to a couple of days ago. It works for me every time.