Fermenting with Raisins

[twobiscuit]

Recently tried using raisins instead of yeast packets to start a cranberry/grape ferment. Within a week, it was bubbling away, and the ferment fragrance smells sweeter and richer than the batches I've done with yeast packets. Anyone have any idea what exactly is the fermentor here? Is it some sort of natural grape yeast in or on the raisins and any guesses as to what quality of wine will be produced?

 

[yaeyama]

Apparently, raisins add a sherry taste to wines. I have never made a raisin wine, but as my wife likes sherry, I will probably have to try it in the future.

 

[twobiscuit]

Yeast type and alcohol content

Anyone know of a table that correlates types of yeast to the percent
alcohol content produced? Thanks.

 

[cpfan]

The amount of alcohol is dependent more on the amount of sugars in the original must. The type of yeast will set a maximum amount of alcohol.

For the five most common Lalvin yeasts see http://www.lalvinyeast.com/strains.asp

Steve

 

[Sacalait]

You likely could have just let the must stand open in the bucket and a ferment would have started. Wild yeast are everywhere. The reason we use the special packets of yeast on the market is because these have proven qualities in enhancing either alcohol content, or possibly add flavors to the wine. Check out one of the yeast providers sites for more info.

If I'm going to put the time, energy and money into say, a 5gal carboy of wine , I want to have a good idea of how it's going to turn out before I start. I use the best available information on yeast beforehand because I don't want any surprises at the end.

 

[yaeyama]

Check out Jack Keller's site, it has a page which lists all the various yeast varieties and why you would want to choose one.

 

[Kivanc]

Just wondering... if I were to collect junipers covered with white layer, I would want to put them in sugared water/juice to cultivate them to be yeast. Am I correct?

 

[stickman]

@Kivanc You're on the right track, but you need to be sure the juice has enough nutrients to propagate the starting yeast. You can search the term "pied de cuve" to find articles about the process, basically it is based on a small volume of fermented musts prepared a few days before harvest and used to inoculate the subsequent batches of grape juice or other must. There are some risks, but some people still choose to use the method. An example article link is below.

Is the “Pied de Cuve” a credible alternative to manage indigenous alcoholic fermentation? – Science & Wine

www.ciencia-e-vinho.com