Beer Yeast Library

Top Quality Liquid Brewing Yeast

The Brewing Science Institute (BSI) is your go‑to source for lab‑grade, ready-to-pitch liquid brewer’s yeast for any type of beer. Our commitment to providing top quality yeast cultures to professional beer brewers ensures you’ll have consistent and successful fermentations every time. Shop our extensive yeast catalog below to find the perfect strain, each available year-round with fast lead times, for your specific needs. BSI is your trusted partner in fermentation excellence.

Express Yeast

Express A-18 London Ale III A top strain for NEIPA's. Fruity ester profile that pairs well with American citrus and tropical… Express A-56 Chico Ale This popular American ale strain is very well balanced. It ferments dry and finishes with a… Express A-72 American Microbrewery Ale A versatile ale yeast with a soft, clean, slightly nutty profile. Finishes with a bit of… Express W177 Kolsch A classic Kölsch strain with a light fruity ester character and low amyl-alcohol production. Can be… Express 3470 German Lager Great choice for a house lager strain. Ferments clean and crisp with residual maltiness. Express Andechs Lager A malt forward German lager strain that ferments clean with a rich malty profile. Perfect for… Express Augustiner A clean and malty all purpose lager with low diacetyl and sulfur production. Express BSI-940 Mexican Lager A great choice for thirst quenching Mexican light lagers. Clean with a crisp finish.

Ale Yeast

1187 Ringwood Ale Very malty profile with distinct fruity esters. Perfect for American brown ales and English pales and… 1868 Pasteur Champagne The classic champagne yeast that ferments fast and clean with a high alcohol tolerance. A-07 German Ale Ferments dry and crisp with a mild but complex flavor profile. Good choice for American fruit… A-10 American White Ale A top choice for American hefeweizens, this ale strain ferments dry leaving a slightly tart and… A-18 London Ale III A top strain for NEIPA's. Fruity ester profile that pairs well with American citrus and tropical… A-28 London Ale I A classic English pub ale strain with a bold, woody, and crisp mineral character suitable for… A-32 British Ale III A British ale yeast with a malty and mild fruity profile and complexity. Great for a… A-35 British Ale II A classic British ale yeast that produces malty beers, with a clean, crisp, and dry finish.… A-38 Old German Ale An ale yeast producing a full-bodied beer with a complex malt profile. Best choice for American… A-56 Chico Ale This popular American ale strain is very well balanced. It ferments dry and finishes with a… A-65 Kolsch This strain produces a subdued fruitiness of an ale with the crisp clean finish of a… A-68 London Ale II A perfect strain for classic English ESB. The mild but complex fruity esters complement malt profiles.… A-69 Timothy Taylor This English strain produces ales with a full, chewy malt flavor. Best used for cask bitters,… A-72 American Microbrewery Ale A versatile ale yeast with a soft, clean, slightly nutty profile. Finishes with a bit of… A-75 Henley on Thames Ale A classic English ale yeast with a fruity and complex flavor profile. Perfect for bitters and… A-78 Scotch Ale A clean fermenting ale yeast with high alcohol tolerance. Perfect for malty high gravity beers of… A-84 Irish Ale An ale yeast with a clean, smooth, and full-bodied flavor profile. Great for stouts and porters. A-98 British Ale A British ale yeast with a dry, crisp, and slightly tart finish. Well-balanced profile with good… A-99 Whitbread Ale An ale yeast with a slightly fruity and mildy malty profile. Not as dry or tart… Akershus Kveik A traditional Kveik strain from Oslo, Norway. Produces very clean, lager-like ales with fast fermentation times.… Andechs Weizen Produces a rich and spicy weizen character ideal for weiss, weizenbock, and American wheat ales. Barbarian A strain famous for brewing NEIPAs. Produces stone fruit esters and flocculates well. BSI-1 American Ale 1 A workhorse strain that ferments clean with a neutral flavor profile with high attenuation that can… BSI-2 English Ale 1 The go-to yeast for classic English ESB, pales, and milds. Complex fruity esters pair well with… BSI-3 German Ale 1 A clean German ale that produces more esters than BSI-29. Great choice for kolsch and alts. BSI-4 Irish Ale A classic Irish ale strain perfect for Stouts and Porters. BSI-5 English Ale 2 Malty profile that finishes estery and fruity. Great choice for browns and pales. BSI-6 English Ale 3 A great choice for cask ales with a distinctive ester profile. High attenuation and flocculation. BSI-7 Dry English Ale 4 Ferments with a clean easter profile and has a high alcohol tolerance. Very flocculant. BSI-8 American Ale 2 A mostly clean flavor profile with slight ester production. Leaves some residual maltiness which can balance… BSI-9 Australian Ale A versatile ale yeast that produces a clean and malty beer with bready esters. BSI-11 German Ale 2 An ale strain that ferments clean with and leaves a malty, full-bodied finish. Used in altbier… BSI-13 English Ale 5 A historic English ale yeast with a rich, minerally profile. Bold woody and crisp character. High… BSI-22 English Ale 6 A top-cropping British ale strain with a flavorful and slightly fruity character. Great for English bitters… BSI-23 English Ale 7 An English ale yeast producing a fruity apple, pear, and honey ester profile. Use in bitter,… BSI-25 English Ale 8 An English ale yeast that produces complex fruity and citrus esters for bitters and pale ales.… BSI-26 English Ale 9 A versatile English ale yeast with a mild, complex and estery profile. Use in a wide… BSI-28 Scottish Ale A top choice for Scotch ales that produces a complex fruity ester profile. High alcohol tolerance. BSI-29 Kolsch Produces a clean lager-like ale, well suited for German kolsch and altbier. BSI-36 Alt Perfect for Dusseldorf style altbier, this strain creates a clean ale with a nice residual sweetness. BSI-41 American Ale 3 Produces a subtle ester profile for a wide range of English and American style ales. BSI-51 American Ale 5 Produces more prominent fruity esters than other American ale strains, and slightly more flocculant. BSI-72 French Ale A clean and malty yeast strain, with a flexible ester profile based on temp range. Great… BSI-90 Southern California Ale A quick fermenting strain that remains clean with low ester production. Similar to BSI-1/A-56 but has… BSI-96 Ale A variant of BSI-1 that also produces a clean and neutral flavor profile with high attenuation. BSI-99 Tom Hardy Ale A perfect strain for high gravity fermentations with a fruity ester profile. Can handle 20% +… BSI-269 Michigan Ale Region: American Strain: Ale Style: Break out your centennial hops and get ready to brew beers… BSI-300 Hefeweizen 1 This classic wheat ale yeast produces a rich banana and clove flavor profile perfect for traditional… BSI-320 Hefeweizen 2 Produces a clean flavored American Hefeweizen with minimal esters and phenols. BSI-335 German Alt A top-cropping, powdery Alt yeast with a wide temperature range for clean to mildly fruity altbier. BSI-351 Hefeweizen 3 This strain produces a classic German-style wheat beer with medium spicy phenolic character. BSI-380 Hefeweizen 4 Produces a prominent clove, nutmeg, and phenol profile, with minimal banana esters. BSI-715 Champagne A clean, fast fermenting champagne yeast that's great for specialty beer and bottle conditioning. CL50 California Pub Ale Produces a classic American silky flavor profile with a well-rounded malty finish that pairs well with… CL980 American White Ale This American wheat yeast creates a very round and clean malt flavor profile, perfect for American… Hornindal Kveik Hornindal kveik. A fast fermenting kveik yeast with a clean, fruity, and tropical ester profile at… Louis P Hard Seltzer Yeast This champagne yeast variant finished dry, crisp, clean, and light. DAP and yeast nutrients should be… Nornes Kveik A traditional Kveik strain from the Nornes farmstead. Produces fruity and floral characteristics. Ferments beyond 90°F.… Voss Kveik A traditional Kveik strain from Norway. Produces a clean and citrus-y flavor profile. Can ferment beyond… W-33 Weizen II A classic German weizen yeast with a well-balanced ester and phenol profile. More flocculant than other… W-38 Weizen A German weizen yeast producing more esters at higher temperatures. Great for weissbiers. W-68 German Weizen This widely used Bavarian wheat ale yeast produces a rich banana and clove flavor profile perfect… W177 Kolsch A classic Kölsch strain with a light fruity ester character and low amyl-alcohol production. Can be…

Lager Yeast

3470 German Lager Great choice for a house lager strain. Ferments clean and crisp with residual maltiness. Andechs Lager A malt forward German lager strain that ferments clean with a rich malty profile. Perfect for… Augustiner A clean and malty all purpose lager with low diacetyl and sulfur production. BSI-800 Czech Lager 1 The top choice for Czech pilsner that produces a clean and refreshing lager with a dry… BSI-802 Czech Lager 2 This Czech lager strain finishes dryer than BSI-800 which makes it a great choice for Bohemian… BSI-810 San Francisco Lager An american lager strain that can produce clean lagers up to 68°F. A great choice for… BSI-820 German Lager 1 This German lager yeast produces rich, malty, and full bodied beers. Perfect for Oktoberfests and dunkels. BSI-830 German Lager 2 This popular German lager strain produces a clean and crisp beer with some residual maltiness. Would… BSI-833 German Lager 3 A German lager strain that produces a perfect malt profile for bock, doppelbock, and Oktoberfest. BSI-838 German Lager 4 This is a great all purpose lager strain for malty but balanced German lagers. BSI-840 American Lager The go-to strain for American style lager. Dry and clean with a very slight tart fruitiness. BSI-920 German Lager 5 A distinct German lager strain that is ideal for dark lagers. Malty with a slight ester… BSI-940 Mexican Lager A great choice for thirst quenching Mexican light lagers. Clean with a crisp finish. BSI-950 Bavarian Pilsner A traditional pilsner yeast from lower Bavaria. High attenuation and low diacetyl. Perfect for German pilsner… BSI-960 Bavarian Bock A traditional German bock yeast from Bavaria. High attenuation and alcohol tolerance. Balanced esters and slight… BSI-970 Bavarian Helles A classic lager yeast from Bavaria. Produces a rich and malty flavor profile with increased sulfur,… BSI-980 Bavarian Dunkel A classic Bavarian lager yeast. Produces a clean and neutral flavor profile allowing malt and hops… Ettal Lager A historic lager yeast that produces a clean, but very malty beer. Use for helles, dunkel,… L-05 Colorado Mountain Lager A lager yeast with light ester production and a mild malty palate. Perfect choice for North… L-06 German 206 Lager This German lager yeast produces rich, malty, and full bodied beers. Perfect for traditional bocks and… L-07 American Megabrewery Lager An American lager strain that ferments dry and crisp with minimal sulphur and diacetyl production for… L-08 German 308 Lager A classic German lager yeast. Sometimes unstable, but smooth, soft, well-rounded, and full-bodied maltiness. L-12 Common Lager This American lager strain can produce clean lagers up to 68°F. Best choice for California Common… L-24 Czech 34/70 Lager This widely used German lager strain produces a clean and crisp beer with some residual maltiness.… L-33 Oktoberfest Lager This is the go-to Oktoberfest lager strain. Produces a rich, malty, complex, and full bodied Festbier. L-35 August Schell Lager A unique and historial American lager yeast that produces a bold, complex, and woody flavor profile. L-42 Denmark Lager A versatile lager yeast with a soft and light flavor profile that accentuates hop charachter. Use… L-47 Denmark Lager II A lager yeast with a clean and dry flavor profile, and slight sulfur produciton. Use for… L-72 Christian Schmidt Lager An American lager yeast with a malty and clean finish. Traditionally used in American pilsner and… L-78 Original Pils Lager The original pilsner strain that produces a clean, crisp, dry, and malty lager that is true… Weltenburg Lager A historic lager yeast that produces a rich and malty profile. Pefect for dunkel and doppelbock.

Belgian / Saison Yeast

ABS3 Belgian Ale Phenolic forward profile with subtle fruitiness. Great choice for a wide range of Belgian styles. B-14 Belgian Ale A Belgian ale yeast with high ester production and alcohol tolerance. Great for dubbel, tripel, and… B-22 LaChouffe An alcohol tolerant, phenolic forward Belgain with mild to moderate fruitiness, good for a wide range… B-42 Essens Wheat A distinctive Belgian yeast with moderate esters and low phenols. Best used in witbier, Belgian IPA,… B-44 Celis This Belgian witbier yeast produces a tart and slighlty phenolic profile perfect for distinctive witbiers and… B-62 Belgian Ale II A classic Belgian strain that produces a balanced fruity aroma and flavor profile with a dry… B-63 Classic Belgian A classic Belgian ale yeast for wit and grand cru styles. Phenolic profile with subdued fruitiness. B-64 Canadian / Belgian Ale A classic Belgian ale yeast with mild phenolics, low esters, and a dry and slightly tart… B-73 Roselare Blend This blend of lambic cultures will produce authentic West Flanders style beers with a complex profile… B-82 Belgian Sour Ale A unique Belgian ale with a balanced ester and phenol profile. Produces organic acids that create… B-87 Trappist Ale This Belgian ale is similar to B-14 but less fruity. A rich distinct ester profile and… B-88 Breendonk Belgian Ale A top strain for Belgian golden strongs. It produces a fruity nose and palate with a… BSI-400 Belgian White Ale 1 The top strain for brewing Belgian witbeirs. Has a pleasant phenolic profile that finishes slightly tart. BSI-410 Belgian White Ale 2 Similar to BSI-400 with more spicy phenol production and lower attentuation for a sweeter witbeir. BSI-500 Trappist Ale 1 Produces a rich, distinct, ripe fruitiness perfect for high gravity dubbel and tripel ales. BSI-510 Trappist Ale 2 A high gravity Trappist ale yeast that prduces a dry beer with a slightly tart finish. BSI-515 Belgian Ale 1 The cleanest Belgian ale strain we offer, perfect for Belgian pales and IPA's. BSI-530 Trappist Ale 3 Similar to BSI-500 but less fruity. Great choice for dubbel, tripel, and Biére de Garde. BSI-540 Trappist Ale 4 A good choice for high gravity Belgian ales with a medium fruitiness right between BSI-500 and… BSI-550 Belgian Ale 3 A phenolic forward Belgain with mild to moderate fruitiness, good for a wide range of Belgian… BSI-565 Saison Produces earthy, peppery, and spicy notes that are found in classic Belgian saisons. Prefers warm fermentation… BSI-566 Saison 2 This Belgian saison produces more fruity esters and less spicy phenols than BSI-565. BSI-570 Belgian Ale 4 Rich fruit and phenolic characteristics with a high alcohol tolerance. Great for high gravity Belgian beers. BSI-575 Belgian Ale Blend 5 A blend of a Trappist and Belgian yeasts. High attenuation and alcohol tolerance for high gravity… S-11 French Saison This extremely attenuative French ale strain produces highly aromatic saisons. Clean citrus esters, peppery, and spicy,… S-24 Saison The classic farmhouse ale yeast that produces earthy, peppery, and spicy notes, with a touch a… S-25 Bier de Garde This French/Belgian strain produces a light ester profile with a sublte spiceness. Malty and sweet that… S-26 Farmhouse Ale This Belgian farmhouse strain produces complex esters balanced with earthy and peppery notes. Finishes dry with…

Wild Yeast

Brettanomyces bruxellensis This strain has medium intensity brett character with fairly mild fruit esters. Great for secondary fermentation… Brettanomyces clausenii This strain has a low intensity brett character and subdued fruitiness. Can be used for primary… Brettanomyces bruxellensis var. Drei This unique brett strain produces a complex earthy profile and more fruity esters than regular bruxellensis.… Brettanomyces lambicus This strain has a high intensity brett character reminiscent of "horse blanket". A classic strain for…

X-Factor TM

X-Tropica^TM Bio-engineered yeast designed to boost tropical flavor compounds using malt based precursors already present in your…

Bacteria

Lactobacillus brevis A lactobacillus strain that can be used for kettle sours and mixed primary fermentations. Slightly more… Lactobacillus delbrueckii A lactobacillus strain widely used for kettle sours and mixed primary fermentations. Pediococcus damnosus Pedio is used in the secondary fermentation of barrel aged sour beers to produce lactic acid.…