Raw Materials

The quality of the raw materials has a direct effect on the quality of the finished product. If you begin with grapes, they should be free of rot. The sugar, pH, and acid levels of the pressed juice, if not already in the desired range, need to be adjusted. Purchase fresh yeast and bacteria cultures and store them properly. Bacteria cultures should be stored in the freezer and the yeast should be stored in the refrigerator. Dates that the material should be used by are stamped on packets by the manufacturer. Out-of-date materials should not be used.

Mark the date that you received your chemicals on the label. Make note of the shelf-life if this information is available. Store chemicals in closed containers, in a cool, dry place.