Yeast and Yeast Nutrient

Yeast

Yeast are living organisms that are the crux of wine-making. In the presence of sugar, yeast can ferment a liquid. The basic (over-simplified) process is that the yeast "eats" the sugar in the liquid--producing carbon dioxide gas and alcohol. The carbon dioxide gas bubbles out of the wine / must and is released into the air, while the alcohol is retained in the liquid. In order for fermentation to occur, the yeast need to multiply. For yeast multiplication to occur, the yeast need sugar (as noted above), nutrient, and ideally should be maintained at temperature between 70 and 80 degrees Fahrenheit.

There are many, many, many types and strains of yeast. Separate broad categories / applications of yeast exist such as baker's yeast, brewer's yeast, granulated yeasts, and of coarse wine making yeast. For making wine, I would strongly recommend that general purpose wine yeast be used. As you gain more expertise with wine making, you will start matching the specific yeast strain to the wine variety. Yeasts such as baker's yeast or brewer's yeast may induce undesirable flavors to the wine.

Yeast Nutrient

Yeast nutrient should be added to the must at the same time that yeast is added. They can be found at most wine making supply stores. The yeast nutrient will provide the necessary vitamins that the yeast need to support a complete fermentation of the must.