Production and Use of Dried Beer Yeast

Lallemand’s core activity Development, production and marketing of… Yeast Bacteria …and their derivatives

Yeast and Bacteria Applications Bread & Baked Goods Beer Animal Nutrition & Health Wine Human Nutrition & Health Distilled Spirits & Fuel Ethanol Plant Care Savoury & Bio Nutrients

Brewer’s ADY Available in different package sizes 500g vacuum pack 11g vacuum sachets

Yeast Culture Collection Short term storage Agar slants Long term storage Liquid nitrogen -196°C Freezer -80°C The integrity and characteristics of the yeast remain intact

Dried Beer Yeast Production Molasses, Water, Salt, Acids, Trace Elements, Vitamins Molasses, Water, Salt, Acids, Trace Elements, Vitamins Culture Media Molasse, Water Nutrients Washing Water -1ºC – 7ºC Lab Cultures 3 Steps Pre Culture 2 Steps Seed Yeast Fermentation Separation Seed Yeast Receiver Commercial Fermentation Washing Water -1 ºC – 7 ºC Commercial Yeast Receiver Separation

Yeast Propagation Batch propagation Fed Batch All nutrients are in fermenter up front Alcohol and little yeast is produced Fed Batch Carbohydrates and nitrogen are added at a certain flow rates Aerobic propagation => Alcohol decreases, yeast production

Main Goals of Propagation Biomass Production Aerobic growth feeding & aeration Yeast conditioning for drying Protein content feeding rate Matured cells feeding rate Trehalose enrichment stress Unsaturated fatty acids aeration Sterols (Ergosterol) aeration

Dried Beer Yeast Production Dryer RVF Extruder -1 ºC – 7 ºC Extrusion Drying Screening Vacuum Packaging Emulsifier QC NaCl Shipping Filtration (RVF) Commercial Yeast Receiver

Quality Control Viability (Methylene blue, YPD) Vitality (Clinitest, Ankom-System) Wild Yeast (Lysine, LWYM, LCSM) Bacteria (PCA, MRS, UBA, SDA) Petite mutants (TTC) Beer fermentation DNA fingerprinting

Typical Analysis Dry weight: 93-95% Viability:  5 x 109 / gram Wild yeast: <1 per 1 million yeast cells Bacteria: <1 per 1 million yeast cells Recommended pitching rate: 100g – 200g per hl

Rehydration Step 1 (Ale Yeast) Sprinkle the yeast on the surface of ten (10) times its weight clean, sterilized (boiled) tap water at 30 – 35 C DO NOT STIR !!! Leave for 15 Min. undisturbed at 30 – 35 C Foam or no foam is no indication of vitality

Rehydration Step 2 (Ale Yeast) After 15 Min. stir gently until all yeast is suspended Leave undisturbed for another 5 Min. Attemperate in steps (5 min) of 10 Celsius degree to the temperature of the wort by mixing aliquots of wort

Rehydration Step 3 (Ale Yeast) After attemperation inoculate without delay Pitching rate: 1 g/L Aeration of wort is not necessary

Bottle conditioning

Why Bottle Conditioned? Longer shelf-life Complexity of flavors Crafty aspect Fresh flavor

How to Bottle Condition? Add fermentable sugars to green beer Bottle beer Production of CO2 under pressure Parameters to consider: Yeast dosage Priming sugar Temperature

Yeast Sources Yeast carried over from primary fermentation Fermenting wort (Krausen) Cropped yeast slurry added post filtration Revitalize cropped yeast Propagated yeast added post filtration Dry yeast added post filtration or without filtration

Bottle conditioning The ideal yeast Alcohol tolerant Stress resistant CO2 production Firm sediment Adequate flavour profile Reproducibility Easy dosage Active Strain Dry Yeast Advantage!

Advantages of Using Dry Yeast Flexibility – always available Easy shipping and storage Consistent cell count for easy dosage Cells rich in sterols and unsaturated fatty acid – ready to divide Selected strains

How to Use Dry Yeast for Bottle Conditioning? Weight the right amount (cell number per g known) Rehydration In water In beer In priming solution Pitching Mixing Bottling

Priming Sugars Glucose/dextrose Sucrose Wort

This Study Yeast (1g per L ≈ 5 x 106/ml) Beer Bottle conditioning Nottingham ale yeast, neutral flocculent Windsor ale yeast, fruity medium flocculent BRY-97 ale yeast, neutral flocculent CBC-1 selected yeast, neutral flocculent Munich wheat beer yeast low flocculent Beer Wheat beer 5% ABV Bock beer 9% ABV Priming Glucose (10g per L) Wort 12°P (100mL per L) Bottle conditioning 1 week at 19 ºC 3 weeks at 11 ºC

Tasting Results Wheat Beer

Tasting Results Bock Beer

Bottle conditioning – Wheat Beer residual sugar analysis 10 g/L Glucose 100 ml wort/L

Bottle conditioning – Bock Beer residual sugar analysis 10 g/L Glucose 100 ml wort/L

Bottle conditioning flavour analysis

Bottle conditioning flavour analysis

Wheat Beer and Glucose Addition Post Conditioning   Gr. beer Munich Windsor Nottingham BRY-97 CBC1 Apparent attenuation [%] 83 87 86 Real attenuation [%] 68 71 70 Alcohol [Vol. %] 5.42 6.24 6.18 6.20 6.04 6.11 CiS [Mio/ml] 5.6 1.9 0.03 0.06 0.1 Total cells [Mio/ml] - 30.4 42.8 9.4 12.3 31.7 Viable cells [%] 81.4 75.7 81.3 74.5 71.9 x3

Wheat Beer and Wort Addition Post Conditioning   Gr. beer Munich Windsor Nottingham BRY-97 CBC1 Apparent attenuation [%] 83 84 Real attenuation [%] 68 Alcohol [Vol. %] 5.42 5.58 5.61 5.27 5.6 CiS [Mio/ml] 0.5 Total cells [Mio/ml] - 10.9 17.7 9.2 11.1 14.2 Viable cells [%] 87 81.4 82.1 80.4 84.3

Bock Beer and Glucose Addition Post Conditioning   Gr. beer Munich Windsor Nottingham BRY-97 CBC1 Apparent attenuation [%] 88 89 Real attenuation [%] 72 73 Alcohol [Vol. %] 8.93 9.51 9.57 9.60 9.55 CiS [Mio/ml] 19 4.7 0.6 2.8 17 Total cells [Mio/ml] - 65 70 68 49 75 Viable cells [%] 39.0 12.5 10.3 24.7 21.6 9.9 x3

Bock Beer and Wort Addition Post Conditioning   Gr. beer Munich Windsor Nottingham BRY-97 CBC1 Apparent attenuation [%] 88 87 Real attenuation [%] 72 71 Alcohol [Vol. %] 8.93 8.61 8.62 8.58 8.67 8.78 CiS [Mio/ml] 19 0.5 0.9 1.5 7.7 1.3 Total cells [Mio/ml] - 75 59 58 52 56 Viable cells [%] 39.0 10.8 14.4 31.5 30.9 14.9 x2

Summary Bottle conditioned beers scored higher Using wort for priming is more stressful for the yeast – less cell division and no production of alcohol Bottle conditioning of high alcohol beers is more stressful for the yeast – less cell division, lower viability and less settling High alcohol beers scored higher with glucose as a priming agent More residual sugars in high alcohol beers and even more when wort is used

How to Pick the Right Yeast? Consider the type of beer to bottle condition Consider the type of priming to be used BRY-97 displayed signs of stress under all conditions Tasting scores for Nottingham were worse after conditioning The use of Munich, Windsor and CBC-1 resulted in the highest tasting scores

TUM Munchen – Weihenstephan Acknowledgments TUM Munchen – Weihenstephan Andreas Marshall Hubertus Schneiderbanger Josef Englmann Sylvie Van Zandycke