Alcotec ReStart yeast strain is especially chosen for its ability to be added straight to a brew with some alcohol already present. It will handle up to 7-8% alcohol without any starter culture required. Use when a wash either doesn't start adequately or gets stuck before it is finished. You should estimate the alcohol level first before adding the yeast. In particular if it is a high alcohol brew that has been fermenting for a while. If above 8%, you must do a starter culture by adding the restart to 1-2 quarts from the wash, diluted by an equal amount of water. Then add this after 12-24 hours when there are good signs of fermentation. 49g sachet.