Fermentis SafLager W-34/70
The dry lager standard — a Weihenstephan 34/70 derivative producing clean, slightly sulphury, deeply attenuating ferments. Bohemian Pilsners and Helles start here.
| SKU | HW-Y-W3470 |
|---|---|
| Price | £7.25 / 11.5g sachet |
| In stock | Yes |
| Origin | France |
| type | dry lager yeast |
| attenuation | 82% |
| flocculation | high |
| temp range c | 12–15 |
| diacetyl tendency | moderate (manage with rest) |
W-34/70 is the dry form of the most widely used lager strain on the planet. It ferments cleanly between 12 and 15 °C, attenuates aggressively, and produces a light sulphur note during primary that conditions out cleanly. Diacetyl management is part of the workflow with any lager strain — give it a 2 °C bump for 48 hours at the end of primary fermentation.
Pitching rate
Lagers need more yeast than ales. For a 20 L batch at OG 1.050:
- 2 sachets pitched cool (10-12 °C) onto well-aerated wort, OR
- 1 sachet plus a 2 L starter
Skimping on pitch rate is the single most common cause of slow, sluggish lager ferments.
Schedule
- Days 1-7: primary at 12 °C
- Days 8-10: diacetyl rest, ramp to 15 °C
- Days 11-21: lager (cold-condition) at 1-3 °C
Used in these recipes
Suits these styles
Learn more
- yeast-selection
- fermentation-basics
- Fermentation control — temperature, schedule, packagingWhy fermentation temperature is the single most important brew-day variable, and how to manage it on a homebrew budget.
- Stuck fermentation — diagnosis and rescueWhen fermentation halts before reaching target FG, what to check first, and how to restart safely.