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HarvInSTL
02-25-2009, 03:03 PM
I noticed that Ken Schramm talked about adding honey when the initial vigorous fermentation slows.

He mentions that he does not follow this method because he thinks that yeast cells are missing nutrients to aid in healthy yeast metabolism.

Does anyone know which exact nutrients that he is referring to?

Also would following an extended SNA help in this situation? I'm jonsing to do a 20%+ mountain berry melomel aged in a port barrel for a couple years.

Thanks!

Medsen Fey
02-25-2009, 03:57 PM
It is not easy to get yeast to go beyond 17-18% ABV. Your best bet is to use step feeding (search that term and you’ll find many threads to give more insight). You also need to manage the fermentation well with good temperature control. How you approach the feeding will also depend on whether you want a sweet or dry result.

The nutrients he is referring to include assimilable nitrogen and various micronutrients including B vitamins, zinc, magnesium, and such. As fermentation slows down, DAP, the common yeast nutrient is not assimilable. Other products that contain only amino nitrogen such as Fermaid 2133, or Fermaid O may still have use even later. Ideally you provide the yeast enough by adding nutrients in stages during the first half of fermentation when they are most able to absorb them. You can search on Staggered Nutrient Addition (or SNA) to find many more threads to peruse.

The problem with step feeding is that it can produce some really harsh results with off flavors and fusel burn that may take more than 2 years to mellow out.

If you post a recipe you have in mind, folks here will help you tweak it to try to get to your goal.

Medsen

And let me not forget,
Welcome to GotMead? !!!