THE CHEMISTRY OF fermentation BREWING CHEMISTRY THE CHEMISTRY OF fermentation

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

BREWING CHEMISTRY ATOMIC STRUCTURE

BREWING CHEMISTRY ATOMIC STRUCTURE

BREWING CHEMISTRY ATOMIC STRUCTURE

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

BREWING CHEMISTRY IONIC BONDS & ions

BREWING CHEMISTRY COVALENT BONDS

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

BREWING CHEMISTRY Water – h2o

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

Water & hydrogen BONDS & ions BREWING CHEMISTRY Water & hydrogen BONDS & ions

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

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

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

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

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

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

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

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

BREWING CHEMISTRY Acids and bases

BREWING CHEMISTRY Acids and bases

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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