Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 25 to 29°C (77°F to 84°F). Leave to rest 15 to 30 minutes. Gently stir for 30 minutes, and pitch the resultant cream into the fermentation vessel. Alternatively, pitch the yeast directly in the fermentation vessel providing the temperature of the wort is above 20°C (68°F). Progressively sprinkle the dry yeast into the wort ensuring the yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes, then mix the wort using aeration or by wort addition.
Sanitize the upper part of the pack (e.g. ethanol 70%) and the scissors before opening. Sprinkle the yeast on the surface of 10 times its weight in clean, sterilized water at 30-35°C (86- 95F). Leave it undisturbed for 15 minutes, stir gently to suspend yeast completely.- Leave it for 5 more minutes at 30-35°C (86- 95F). Attemperate in steps at 5-minute intervals of 10°C to the temperature of the wort by mixing aliquots of wort in order to adjust the temperature of the hydrated yeast, with no delay.
For all strains except lager yeasts, add the sachet contents to 100 ml (3.4 US fl oz) of water previously adjusted to a temperature between 30–35°C (86–95°F). For lager yeasts, rehydrate using 100 ml (3.4 US fl oz) of 20–25°C (68–77°F) water. Stir gently into a yeast cream for between 8-12 minutes then add yeast cream directly to wort. Alternatively the dry yeast can be added directly to the wort by sprinkling onto the surface and leaving to stand for 10-15 minutes before stirring.
Lalvin Wine Yeast
1. Rehydrate the yeast in 50ml of water, at a temperature between 35-37°C (95-98.6°F).
2. Dissolve by gently stirring and wait for 20 minutes.
3. Add the must. The difference in temperature between the must to be inoculated and the rehydration medium should not be higher than 10°C (if necessary, acclimatize the temperature of the medium by slowly adding must).
4. The total rehydration time should not exceed 45 minutes.
5. It is crucial that a clean container is used to rehydrate the yeast.
6. Rehydration in must is not recommended.