Yeast. Jasper Akerboom Lost Rhino Brewing Company

Transcription

1 Yeast Jasper Akerboom Lost Rhino Brewing Company

2 Pace, NR. Science 276: (1997)

3 Yeasts: Single cell Fungi - Over 1500 species known Number will increase Different cell sizes and morphologies Different colors and colony shapes For brewing, mainly three genera are used: Saccharomyces, Torulaspora delbrueckii, Dekkera/Brettanomyces S. cerevisiae Slide from Diego Libkind

4 Brettanomyces Saccharomyces Homo sapiens Lactobacillus Brettanomyces Saccharomyces lactate dehydrogenase alcohol dehydrogenase pyruvate decarboxylase acetaldehyde dehydrogenase acetic acid Total ~30-32 ATP (not 36) Alba-Lois, L. & Segal-Kischinevzky, C. (2010) Nature Education 3(9):17, Stryer, L. Biochemistry, 4 th edition (1995)

5 Saccharomycetales family Brett Sake yeast Hefeweizen Ale Suh et al., Mycologica 2006

6 Saccharomyces cerevisiae 1 The most used ale yeast, regarded pure strain 1 Wang, QM et al., Mol. Ecol. (2012) 2 Pengelli, R.J. et al., FEMS Yeast Research (2013) 3 Libkind, D. et al., PNAS (2011) 4 Gonzáles, S.S. et al., Appl Environ. Microbiol. (2008) Saccharomyces bayanus 2 champagne yeast : hybrid strain (S. eubayanus, S. cerevisiae, S. uvarum) Saccharomyces pastorianus 2 carlsbergensis lager yeast, hybrid S. bayanus and S. cerevisiae (or S. eubayanus and S. cerevisiae) Saccharomyces uvarum 3 lager yeast, hybrid S. cerevisiae and S. monacensis Belgian Strains 4 : S. cerevisiae x S. kudriavzevii hybrids.. Very complex, and lots of horizontal gene transfer /mixing/breeding

7 Guilliermond, A. Les Levures. Encyclopedie Scientifique. O. Doin et Fils, Paris (1912) H. Phaff, A. Martini 1980 s strains of S. cerevisiae are rarely if ever present on the fruits and berries of wild species of plants The Life of Yeasts - Phaff et al S. cerevisiae must be associated with some other ecological niche Peynaud and Domerq A review on microbiological problems in wine making in France Slide from Jose Sampaio

8 Ale yeast, pure strain, can be isolated from Oak bark (17%), forest soil (14%), rotten wood (9.2%), orchard soil (9.1%), fruit samples (6%) (grapes are the lowest success rate!!) Wang, QM et al., Mol. Ecol. (2012)

9 Saccharomyces spp. thrive off Cyttaria fungus fruiting bodies (~10% sugar) Lager yeast grows in colder months, Ale yeast in the warmer months

10 The tree bark system harbors multiple (all?) Saccharomyces species S. cerevisiae S. paradoxus S. cariocanus S. mikatae S. arboricolus S. kudriavzevii S. pastorianus S. bayanus S. uvarum Sampaio and Gonçalves Appl Env Microbiol 74: and unpublished work Localities Samples Europe 164 (Portugal, Germany) North America 96 (Canada) South America 52 (Argentina) Oceania 64 (Tasmania, New Zeal.) Asia 155 (Japan) Total 531 Quercus pyrenaica 73% Quercus faginea 71%

11 Brettanomyces Genome size: Homo: 3000Mb Saccharomyces: 12MB Brettanomyces: 19-30Mb DNA level: Brett brux Brett anomalus h<p://

12 Brettanomyces spp: (sometimes called wild yeast) Spoilage yeast in Food Industry (wine, but also beer) Pellicle former Can ferment complex carbohydrates, whatever Saccharomyces leaves behind boom/pop Same strain Same organism Vinyl phenols Ethyl phenols Biogenic amines Putrescine Cadaverine Spermidine Acetic acid (oxygen cond.) Brettanomyces has been studied in much less detail than Saccharomyces

13 Solid Media (2% peptone, 1% yeast extract, 2% maltose - agar plates and potato-agar* plates) Low Gravity Liquid Media (2% peptone, 1% yeast extract, 2% maltose) High Gravity Liquid Media (2% peptone, 1% yeast extract, 30% maltose**) Air incubate for h Air incubate for 1-6 weeks Air incubate for 1-6 weeks Incubate at 25 C (77 F) for 2-3 weeks Ferment and isolate organisms * **F. Noé Arroyo-López et al. Int J of Food Microbiol 131 (2009) Streak fermenting liquid/ colonies on YPM agar Supplemented with 100μg/ml ampicillin

14 Both YPM and potato agar showed growth Both high-gravity and low-gravity YPM showed growth Stereo Microscope streak and select single colonies grow small (5ml) cultures

15 Micrographs phase contrast (FOV 50-72μm)

16 Strains were grown in 100ml YPM supplemented with ampicillin 100μg/ml for ~2 days shaking 200rpm at 28 C (82.4 F) Teaspoon of malt extract was added after two days, plus 50μl 100mg/ml ampicillin (keeps bacteria at bay) Two extra days shaking to increase cell numbers for pitching The cultures that did not grow were discarded

17 NY State Where are we now Ini%al Growth Gravity (P) (6 weeks in) Smell/Taste Air1 No Fermenta%on - Air2 No Fermenta%on - Air ok Air4 Did not grow - Air5 Did not grow - 8 out of 41 enjoyable after just 6 weeks NY Grainy Fruity Pleasant NY Very awful - discard Questionable Barrels W1 5.3 Very Clean, Honey W2 5.6 Tart Citrus W3 No Fermenta%on Very Ropey W ok W ok W Dumped W ok W8 6.8 Grainy, pleasant, fruits W9 16 Discarded W10 No Fermenta%on W11 No Fermenta%on All fermenting ones have been bottled Ashburn Air YF Discarded YF2 Did not grow YF3 6.3 ok YF ok YF5 5.6 Rancid buxer YF6 4.5 socks YF7 No Fermenta%on YF ok YF9 Did not grow YF apple, fruity loops YF BiXer smell/taste YF Socks sweat locker room YF ok YF13 Too bad to measure Discard YF YF Sour Apples Tart YF ok YF BreX tart nice YF Not very great YF Very awful YF Taste is bixer aroma clean Controls WB1 7.1 Aroma%c BreX, Fruity WY1 5.1 Clean ok WY2 5.1 Clean ok LRB 0.5 Clean, fruity, BreX Fantome 8.05 Nice belgianesque

18 Further information on isolating/growing yeasts Books: - Yeast (Jamil Zainasheff and Chris White) ~$12 - The Yeast in the Brewery (VLB Series) ~$100 - Yeasts, a taxonomic study ~$600 - Brewing Yeast and Fermentation (Boulton)? - Brewing Yeast Fermentation Performance (Smart)? - Brewing Microbiology (Priest and Campbell)? - Microbial Applications (Benson)? Worldcat.org interlibrary loan ~$2 Online: h<p://homebrewtalk.com h<p://realbeer.com/spencer/yeast- culturing.html h<p:// h<p:// h<p://jaapie.org h<p://eurekabrewing.wordpress.com etc..

19 Ok we have the info. What do we really need? 1. Notebook 5 dollar 2. Pressure cooker 50 dollar 3. Bunsen- burner 2.30 dollar Do not use an alcohol lamp. The flame is too slow. Hook up to a small propane burner. 4. Glassware Spend as li<le money as possible. Reuse sauce jars, jam jars, ball jars. Buy tubes with black screwcap, and some erlenmeyers (total ~30 dollar).

20 5. Stirplate 12 dollar (+5 dollar stirbar) h<p:// shamelessly- cheap- 12- diy- stir- plate / 6. Inoculation loop 5 dollar for 3 7. Petri dishes 10 dollar for 5, glass 8. Agar Telephone- brand, Asian supermarket 9. Spray botle 5 dollar

21 10. Stuff you already own: - Microwave - Aluminium foil - Lighter 11. Microscope and accessories: - Phase contrast if possible, dollar, ebay etc

22 Work Sterile Work under a flame, do not rush, make sure everything is close, flame everything Do not wear gloves like these people.

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25 Yeast Starters: Aerobic conditions result in greater cell mass (and good for fatty acids sterols) 9 grams per liter of glucose: Crabtree effect will force cells into fermentation mode 9 grams/liter = = 0.9 P - Use low gravity wort for starters - Aerate continuously (aeration stone, shaker, no pure O 2 ) - Add yeast extract (servomyces/boiled yeast cells) - add protein source (nitrogen/amino acids) - its ok to grow the cells at 30 C (86 F)

26 Thanks!