1. THE CHEMISTRY OF fermentation
BREWING CHEMISTRY
THE CHEMISTRY OF fermentation

2. 4 basic ingredients: Water - Malted Barley - Yeast - Hops
BREWING CHEMISTRY
4 basic ingredients:
Water - Malted Barley - Yeast - Hops

3. BREWING CHEMISTRY
ATOMIC STRUCTURE

4. BREWING CHEMISTRY
ATOMIC STRUCTURE

5. BREWING CHEMISTRY
ATOMIC STRUCTURE

6. H, N, C, O, Na, P, Ca, K, Mg S, Cl, F, Zn, Cu, Fe, I, Hg, Br, Pb
BREWING CHEMISTRY
H, N, C, O, Na, P, Ca, K, Mg S, Cl, F, Zn, Cu, Fe, I, Hg, Br, Pb
ATOMIC STRUCTURE

7. BREWING CHEMISTRY
IONIC BONDS & ions

8. BREWING CHEMISTRY
COVALENT BONDS

9. COVALENT BONDS - NON-POLAR MOLECULES/POLAR MOLECULES
BREWING CHEMISTRY
COVALENT BONDS NON-POLAR MOLECULES/POLAR MOLECULES

10. BREWING CHEMISTRY
Water – h2o

11. Water & hydrogen BONDS & ions
BREWING CHEMISTRY
H2O: charged molecule which can bond to many molecules
Water & hydrogen BONDS & ions

12. Water & hydrogen BONDS & ions
BREWING CHEMISTRY
Water & hydrogen BONDS & ions

13. Water & hydrogen BONDS & ions
HYDROGEN BONDS 1. Are moderately strong intermolecular bonds; they serve as links between molecules.
2. Help determine three-dimensional shape
3. Forms liquid water
4. Considerable cohesion which creates a very high surface tension 5. Formed between POLAR molecules– most molecules are POLAR 6. Helps hold many natural molecules together
BREWING CHEMISTRY
Ex- H-bonds hold starch molecules together in barley seed: we break them apart in the first part of the mashing/cooking process
Water & hydrogen BONDS & ions

14. 4 basic ingredients: Water - Malted Barley - Yeast - Hops
BREWING CHEMISTRY
4 basic ingredients:
Water - Malted Barley - Yeast - Hops

15. Water – THE UNIVERSAL SOLVENT
H20: beer + life 1. Universal solvent 2. Necessary for all life’s chemical reactions 3. Chemical reaction medium for: a. Fermentation b. All living cells (yeasts) 4. Stable temperatures for life (high E storage in H-bonds later) 5. High surface tension and cohesion– “sticky” Q- type of bond?
BREWING CHEMISTRY
Water – THE UNIVERSAL SOLVENT

16. Water – THE UNIVERSAL SOLVENT
BREWING CHEMISTRY
H20 and BREWING 1. Universal solvent- MASHING (breaking down large sugar to small simple sugars) 2. Chemical reaction medium for Fermentation 3. Stable temperatures – lots of E for mashing, boiling. 4. Cleaning
Water – THE UNIVERSAL SOLVENT

17. Water – THE UNIVERSAL SOLVENT
BREWING CHEMISTRY
Water for: CLEANING; HEATING and COOLING
Brewing LIQUOR- mashing + fermentation
Water – THE UNIVERSAL SOLVENT

18. H20 AND MIXTURES 1. SOLUTION 2. COLLOID 3. SUSPENSION
BREWING CHEMISTRY
H20 AND MIXTURES 1. SOLUTION 2. COLLOID 3. SUSPENSION
Water – THE UNIVERSAL SOLVENT

19. Chemical reactions: how to read this shtuff
BREWING CHEMISTRY
C6H1206 → C2H5O + CO2
C6H O2 → H2O + CO2
Chemical reactions: how to read this shtuff

20. 2 MAJOR CHEMICAL RXN TYPES 1. Decomposition. 2. Synthesis
2 MAJOR CHEMICAL RXN TYPES Decomposition Synthesis *Energy and Chemical Rxns: *Temperature and Chemical Rxns?
BREWING CHEMISTRY
Chemical reactions

21. BREWING CHEMISTRY
Acids and bases

22. BREWING CHEMISTRY
Acids and bases

23. Acids and bases Acid- a chemical below 7.0 on the pH scale
Acidic is the adjective for acid
BREWING CHEMISTRY
Base- a chemical above 7.0 on the pH scale
Alkaline is the adjective for base
Pure Water is neutral (7.0 on the pH scale) : neither an acid nor a base
Acids and bases

24. which can ruin a batch of beer
BREWING CHEMISTRY
The proper pH of solutions in the brewing process is vital for a quality product
For example in the Mashing Process, the mash should have a pH between 5.2 – 5.6
Improper pH can result in many problems, including the production of off-flavors,
which can ruin a batch of beer
Acids and bases

25. Acids and bases pH buffer: A chemical of the opposite pH.
BREWING CHEMISTRY
pH buffer: A chemical of the opposite pH.
Example—the mashing pH is too alkaline (greater than 5.6),
so you can add an acid to bring the pH back down into range.
BREWING BUFFERS:
Bicarbonate—increases pH
Phosphoric acid—decreases pH
Acids and bases

26. BREWING CHEMISTRY
Ions play important roles in living organisms, including yeasts.
They are important in overall health and chemical reactions the
organisms participate in.
Ions and beer

27. BREWING CHEMISTRY
Calcium (Ca2+) and Magnesium (Mg2+) are vital for normal and happy yeasts
Sometime these ions need to be added to the brewing water for happy yeasts
Ions and beer

28. Other Important Brewing Ions:
Ca+ -- Can also be used as an acidic buffer.
source: calcium chloride, calcium carbonate, calcium sulfate
Na+ (sodium)– used as alkaline buffer
source: sodium bicarbonate
CO3- (Carbonate ion)– originates from CO2 from
yeast fermentation: can increase the pH
HCO3- (Bicarbonate ion)– also originates from CO2 from yeast fermentation: can increase the pH
Fe+ (Iron)– can be present in water from pipes;
not good for brewing
BREWING CHEMISTRY
Ions and beer

29. Hard and Soft Water Ions and beer
Hard water contains high ion content, like Ca+
and Mg+
Soft water is the opposite: low ion content
BREWING CHEMISTRY
Ions and beer

30. If water needs to be “adjusted” after treating or purifying water, ions can be added back for the best water for brewing.
Calcium sources:
Ca chloride hydrate
Ca dihydrate
Ca sulfate
Ca carbonate
(Ca levels for happy yeasts should be about 50ppm)
Magnesium source:
Mg sulfate (Epsom salts)
BREWING CHEMISTRY
Ions and beer

31. Water treatment for brewing preparation
BREWING CHEMISTRY
POLLUTANT: anything not wanted in our brewing LIQUOR
Water treatment for brewing preparation

32. Water treatment for brewing preparation
BREWING CHEMISTRY
WATER TREATMENT: PURIFYING water for brewing
Water treatment for brewing preparation

33. Water treatment for brewing preparation
BREWING CHEMISTRY
Filtration
Iron Removal
Reverse Osmosis
Ion Exchange
Activated Charcoal
Oxygen Removal
Boiling
Water treatment for brewing preparation

34. 4 basic ingredients: Water - Malted Barley - Yeast - Hops
BREWING CHEMISTRY
4 basic ingredients:
Water - Malted Barley - Yeast - Hops

35. CARBOHYDRATES Carbohydrates Primary Function: ENERGY
We can get carbohydrates from fruits, vegetables, pasta, cereal grains
BREWING CHEMISTRY
CARBOHYDRATES

36. CARBOHYDRATES Carbohydrates’ other function: STRUCTURE
BREWING CHEMISTRY
Carbohydrates’ other function: STRUCTURE
The most common structural carbohydrate is cellulose.
Structural polysaccharides cannot be broken down by most organisms for energy
Structure for:
Seed hulls (coat) of cereal grains
Seed diagram
CARBOHYDRATES

37. CARBOHYDRATES Energy carbohydrates come in 2 forms:
Simple sugars (monosaccharides and disaccharides):
glucose
lactose
sucrose
fructose
2. Complex sugars (polysaccharides):
starch-- which is many glucose molecules bonded together
cellulose (seed hulls)
BREWING CHEMISTRY
glucose
starch
CARBOHYDRATES

38. Yeasts eat the simple sugars from barley grains for ENERGY and produce ethanol and CO2 as by products.
BREWING CHEMISTRY
yeast
Simple sugars that yeast can eat: glucose
maltose
maltotriose
Simple sugar source: Conversion of starch from barley grains by mashing
barley
CARBOHYDRATES

39. CARBOHYDRATES Cereal grains like barley, are seeds.
Seeds contain 3 primary parts:
1. Seed coat or hull
2. Embryo- baby plant
3. Cotyledon- starch for energy for the soon to be growing plant.
BREWING CHEMISTRY
barley
The starch is too large of a molecule for
yeasts to eat…so the starch in the barley grain has to be broken down into
“chewable” simple sugars for the
yeast.
The starch is broken down into simple sugars in the Mashing Process
CARBOHYDRATES
yeast

40. glucose, maltose, maltotriose enzyme stimulation
BREWING CHEMISTRY
mashing
starch
glucose, maltose, maltotriose
enzyme stimulation
CARBOHYDRATES

41. Other carbohydrates pertinent to brewing:
Dextrins: sugar molecules larger than
3 simple sugars—
not digestable by yeast;
can be left in beer for sweetness
and mouthfeel
Fructose: simple sugar found in fruits—
typically not to be used in brewing, as gives a cidery flavor
Beta glucam gum: larger polysaccharide found in seed hulls. More prevalent in rye and wheat.
Can thicken and gum up the mash– not good.
BREWING CHEMISTRY
Mashing process
CARBOHYDRATES

42. Malted barley + hot water + enzymes simple sugars
What is Mashing?
BREWING CHEMISTRY
Mashing is the process of turning the complex carbohydrate—starch—of the malted barley, into simple sugars—glucose, maltose, and maltotriose—that yeast can eat to produce ethanol and carbon dioxide through fermentation.
With the help of ENZYMES
Malted barley + hot water + enzymes simple sugars

43. Proteins are vital to ALL LIVING THINGS / Proteins have many functions:
BREWING CHEMISTRY
proteins

44. proteins Proteins have many functions; 2 of which are:
1. Physical protection– like in seed hulls
2. Enzymes– vital for all chemical reactions in living things.
BREWING CHEMISTRY
proteins

45. proteins Proteins in beer are necessary for good beer foam (head)
BREWING CHEMISTRY
…And healthy, happy yeasts
proteins

46. proteins Too many proteins from grain hulls can cause hazy beer
BREWING CHEMISTRY
proteins

47. proteins ENZYMES: biological catalysts (speed up chemical reactions)
vital for chemical reactions
functions depend on their shape
shape (therefore, function) can be disrupted by many things :
including improper Temperature and pH
BREWING CHEMISTRY
Shape = Function
Special shape of enzyme allows for chemical reaction to occur
proteins

48. proteins ENZYMES: functions depend on their shape
shape (therefore, function) can be disrupted by many things :
including improper Temperature and pH
BREWING CHEMISTRY
Shape = Function
Disruption of protein/enzyme shape = DENATURING
this is why proper TEMPERATURE and pH are vital to good beer
proteins