MASHOUT MAGAZINE

When it comes to dry lager yeast, most homebrewers immediately reach for one strain: W 34/70. It has become the gold standard for clean, crisp, reliable lager fermentation. Because of that, another strain from Fermentis often gets pushed to the side entirely: SafLager S-23.

When I talk to other homebrewers about S-23, the response is usually pretty similar. A lot of brewers either have never used it, have barely heard of it, or simply say they have always defaulted to 34/70 instead. And that makes sense. W 34/70 has earned its reputation for being dependable and extremely versatile.

But maybe that is exactly why S-23 gets overlooked.

If you spend enough time reading brewing forums or social media discussions, you will notice that S-23 has developed a bit of a reputation. Brewers often describe it as fruity, less clean, or too expressive for traditional lager brewing. For years, it has lived in the shadow of more neutral strains.

But maybe that reputation misses the point.

After brewing with S-23, it becomes pretty clear that the strain is not trying to be another version of 34/70. Instead, it offers something slightly different. Rather than disappearing completely into the background, S-23 contributes a subtle character of its own. When fermented properly, that character can bring softness, rounded malt flavor, and a touch of complexity that works beautifully in the right styles. That is especially true for American lagers.

Modern lager brewing has become obsessed with the idea of extreme crispness and total neutrality. While there is certainly a place for that, not every lager needs to taste stripped down and flavorless. Some of the best easy drinking lagers still carry a little personality behind the crisp finish.

That is where S-23 shines. The strain tends to leave a fuller mouthfeel than many ultra dry lager yeasts, helping lower ABV beers feel more balanced and complete. It also complements adjunct heavy recipes extremely well, especially beers brewed with rice or corn. Instead of tasting thin, the finished beer develops a smoother texture and a softer malt profile that makes it incredibly drinkable.

For brewers making classic American lagers, lawnmower beers, or everyday house lagers, those qualities can be a huge advantage. S-23 also feels surprisingly old school in the best way possible. Many historical American lagers and regional light lagers were not perfectly sterile tasting beers. They often carried subtle fermentation character, gentle fruitiness, and a rounded malt backbone that gave the beer life. S-23 brings some of that character back into modern homebrewing without losing the refreshing qualities people expect from a lager.

Of course, fermentation temperature still matters. S-23 performs best when treated like a true lager strain. Cooler fermentation temperatures and healthy pitching rates help keep the profile balanced and smooth. Fermented too warm, the yeast can become much more expressive and fruit forward than some brewers expect.

When handled correctly, S-23 produces beers that feel approachable, flavorful, and incredibly easy to drink. Check out this award winning recipe below for an easy drinking, and crushable American Lager that features S-23.

Default
72% efficiency
Batch Volume: 5.5 gal (20.8 L)
Boil Time: 60 min

Water
Mash Water: 4.52 gal (17.1 L)
Sparge Water: 3.16 gal (12 L)
Total Water: 7.68 gal (29.1 L)
Boil Volume: 6.8 gal (25.7 L)
Pre-Boil Gravity: 1.043

Vitals
Original Gravity: 1.048
Final Gravity: 1.009
IBU (Tinseth): 18
BU/GU: 0.36
Color: 2.4 SRM (4.7 EBC)

Mash
Protein Rest — 125 °F (52 °C) — 15 min
Alpha Amylase Rest — 148 °F (64 °C) — 30 min
Beta Amylase Rest — 156 °F (69 °C) — 30 min
Mash Out — 170 °F (77 °C) — 15 min
OR Single Mash Infusion at 150°F (65°C) — 60 min

Malts (10 lb / 4.54 kg)
6 lb (2.72 kg) (60%) — Montana Craft Pilsner Malt
4 lb (1.81 kg) (40%) — Flaked Torrefied Rice

Hops (1 oz / 28 g)
1 oz (28 g) (18 IBU) — Liberty Hops 5% AA — 60 min

Misc
0.3 g — Calcium Chloride (CaCl2) — Mash
0.7 g — Gypsum (CaSO4) — Mash
7 ml — Lactic Acid 80% — Mash
0.3 g — Magnesium Chloride (MgCl2) — Mash
0.3 g — Calcium Chloride (CaCl2) — Sparge
0.7 g — Gypsum (CaSO4) — Sparge
0.3 g — Magnesium Chloride (MgCl2) — Sparge

Yeast
3 pkg — Fermentis S-23 SafLager West European Lager

By Jordan, Billy’s Tavern Homebrewing

Jordan is a California native. When he is not brewing he can be found drinking beer with friends, duck hunting, and getting lost in a good book or video game. When he is not out on an adventure with his wife, he can be found at home with his two lovable dogs. Stay up to date by following him on Instagram.

Fermentis S-23 Yeast Packet Photo From Craft a Brew