yeast questions

[twobiscuit]

Do yeast reproduce in the must and increase in numbers, or is it just whatever set number of them in the packet that do all the fermenting?


Also, when someone mentions 15% alcohol content, what is the other 85%? Mostly water and flavanoids? Unfermented sugar and water?

Thanks, just a newbie!

 

[Luc]

Yeast can live in two different environments.

The first is aerobic meaning with oxygen.
The must is in the primary fermenter and there is a lot of air above it. The yeast will then multiply and produce less alcohol.

When we transfer the must to secondary and put an air-lock on the yeast goes into the other stage: an-areobic where it will produce more alcohol and reproduces less.

But in both fases the yeast will multiply.

Considering the second question:
Indeed the rest of the beverage is water, sugar, acid, color components, tannins, sulphite.

Hope this answers your questions.

Luc