what’s on the menu? fundamentals of yeast nutrition dawn maskell international centre for brewing...
DESCRIPTION
Food, glorious food! wortyeastbeerTRANSCRIPT
![Page 1: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/1.jpg)
What’s on the menu?Fundamentals of yeast nutrition
Dawn MaskellInternational Centre for Brewing & DistillingHeriot-Watt UniversityEdinburgh, UK
![Page 2: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/2.jpg)
YEAST NUTRITIONWhat is it and why do we care?
![Page 3: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/3.jpg)
Food, glorious food!
wort yeast beer
![Page 4: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/4.jpg)
How do yeast eat?
![Page 5: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/5.jpg)
How does yeast make alcohol?
![Page 6: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/6.jpg)
YEAST DIET: THE ESSENTIALS
![Page 7: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/7.jpg)
Brewers’ wort Carbohydrates
Glucose Fructose Sucrose Maltose Maltotriose Maltotetraose and larger
dextrins Vitamins Nucleic acids Hop components
Free Amino Nitrogen (FAN) Amino acids Ammonia Small peptides
Glycopeptides and proteins
Water Ions Melanoidins
![Page 8: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/8.jpg)
CarbohydratesWort Fermentable Sugars
Fructose ~ 2 % Glucose ~ 8 % Sucrose ~ 6 % Maltose ~ 45 % Maltotriose ~ 10 %
Uptake Of Wort Sugars
0 24 48 72 96 120 1440
10
20
30
40
50
60
70
80
90
Glucose Fructose MaltoseMaltotriose Dextrins
Fermentation Time (hours)
Car
bohy
drat
e (g
/l)
![Page 9: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/9.jpg)
Oxygen: opportunity and threat Absence of oxygen – only
fermentative growth Synthesis of sterols and UFA’s
(biomass – membrane components essential for growth)
Oxygen depleted – division and growth restricted – become fully fermentative
![Page 10: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/10.jpg)
Free Amino Nitrogen Source of nitrogen Levels? Ale yeast higher
FAN needs than lager
Protein stand/rest
![Page 11: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/11.jpg)
Valine: the villain of the piece? Vicinal diketones – by-
products of valine and isoleucine
Supplementation reduces diacetyl formation!
![Page 12: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/12.jpg)
Proteins: friend or foe? Nutrition
But only as amino acids or small peptides
Cell structures Higher alcohols
Haze Protein-polyphenol complexes
forming permanent or non-permanent hazes
Foam Foam positive proteins contribute
to head formation
![Page 13: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/13.jpg)
SOMETHING IN THE WATER?The role of micronutrients
![Page 14: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/14.jpg)
The need for ionsIon FunctionZinc Essential for growth, enzyme co-factor, stress
protectant against ethanol toxicityManganese Enzyme co-factor, cell and organelle structure
Magnesium Essential in many enzymes involving ATP, cell and organelle structure
Calcium Stimulates growth, depresses wort pH, and has a role in flocculation
Copper Enzyme co-factor, binds to some proteins
Potassium Component of transport system for nutrient uptake
Phosphate Synthesis of organic phosphorus containing compounds
Sulphate Synthesis of S – containing compounds
![Page 15: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/15.jpg)
Other roles of ions
Zinc Protect against ethanol stress
Magnesium Stabilising membrane, inhibit stress induced proteins
Calcium Flocculation at end of fermentation, protect against ethanol stress
Copper Eliminate H2S from beer as insoluble hydrogen sulfide
Chloride Inhibitory at high concentrations
Iron Toxic to yeast
![Page 16: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/16.jpg)
VITAMINS
![Page 17: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/17.jpg)
Vitamins
Many essential vitamins cannot be synthesised by yeast Biotin Pantothenic acid Nicotinic acid Thiamine (Vitamin B)
![Page 18: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/18.jpg)
NOT ALL NUTRITION IS EQUAL
![Page 19: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/19.jpg)
Wort Soup Nutritional variation
Strain specific Between breweries (same
strain) Water supply Grist composition and adjunct
use Brewhouse design Environmental conditions Brew length and type of beer
produced
Yeast ignores Dextrins β-glucans Pentosans Large proteins Phenolics
![Page 20: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/20.jpg)
Yeast Food Prevent slow
fermentations Useful for high
adjuncts/low nitrogen worts
Consistent fermentations
![Page 21: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/21.jpg)
PRACTICAL CONSIDERATIONS
![Page 22: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/22.jpg)
Practical considerations Ethanol stress Using antifoams Use of stabilisation products
![Page 23: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/23.jpg)
THE YEAST MENUThe fundamental takeaway messages
![Page 24: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/24.jpg)
Takeaway menu The diversity of yeast nutritional needs What can be essential can also be toxic in
excess Supplementation can make up for
deficiencies
![Page 25: What’s on the menu? Fundamentals of yeast nutrition Dawn Maskell International Centre for Brewing & Distilling Heriot-Watt University Edinburgh, UK](https://reader035.vdocument.in/reader035/viewer/2022062905/5a4d1ad77f8b9ab0599737f6/html5/thumbnails/25.jpg)
THANK YOUAny questions?