Alcohol Fermentation Overview

Fermentation

Metabolic process converting carbohydrates into alcohol, acids, or gases by microorganisms.

Alcoholic Fermentation

Type of fermentation by yeast converting sugars into ethanol and carbon dioxide.

Saccharomyces cerevisiae

Common yeast species used in alcoholic fermentation.

Zymase

Enzyme in yeast converting sugars to ethanol and carbon dioxide.

Maltase

Enzyme in yeast cells that catalyzing the hydrolysis of maltose into 2 molecules of glucose.

Ethanol

Synonym for alcohol; primary product of alcoholic fermentation.

Carbon Dioxide

By-product of fermentation from fermenting microorganisms.

Lactic Acid

By-product in production of fermented dairy and vegetable products.

Acetic Acid

By-product of acetous fermentation, known as vinegar fermentation.

Carbonic Acid

Formed when carbon dioxide dissolves in water during fermentation.

Glycerol

By-product of alcoholic fermentation produced by yeast during the conversion of sugar to ethanol.

Alcohol Proof

Measure of alcohol concentration in a beverage; double the alcohol by volume percentage.

Scotch

Whisky made from malted barley and water.

Rye Whiskey

Whiskey similar to Bourbon but primarily made from rye grain.

Bourbon

Whiskey made from at least 51% corn along with other grains.

Rum

Made from sugarcane, molasses, or sugarcane juice.

Vodka

Can be made from various ingredients like grains, potatoes, or grapes.

Invertase Reaction

When added to sucrose (table sugar) or foods that include sucrose adds with water, it splits the sugar into its component parts of glucose and fructose.

C12H22O11 (sucrose) + H2O (water) -> C6H12O6 (glucose) + C6H12O6 (fructose)

Chemical reaction of invertase reaction

C6H12O6 (glucose) -> 2 C2H5OH (ethanol) + 2 CO2 (carbon dioxide)

Chemical reaction of Fermentation by yeast

C6H12O6 (glucose) -> 2 C2H5OH (ethanol) + 2 CO2 (carbon dioxide)
C12H22O11 (sucrose) + H2O (water) -> C6H12O6 (glucose) + C6H12O6 (fructose)

Fermentation process

Test for carbon dioxide

Involves bubbling the gas through an aqueous solution of calcium hydroxide (lime water). If the gas is carbon dioxide, the limewater turns milky or cloudy. Is slightly soluble in water and precipitates as white solid.

Ca(OH)2(aq) + CO2(g) =

CaCO3(s) + (H2O)

Ca(OH)2

Calcium hydroxide (lime water)

CO2

Carbon dioxide

CaCO3

Calcium carbonate (makes lime water milky)

H2O

Water

Ca(OH)2(aq) + CO2(g) -> CaCO3(s) + (H2O)

Test for CO2

Iodoform Test

used to check the presence of carbonyl compounds with the structure R-CO-CH3 or alcohols with the structure R-CH(OH)-CH3 in a given unknown substance.

The reaction of iodine, a base and a methyl ketone gives a?

yellow precipitate along with an "antiseptic" smell

Alcohol

an organic compound in which an -OH group is bonded to a saturated carbon atom.

Hydroxyl group

The -OH group, the functional group that is characteristic of an alcohol

Classifications of Alcohols

primary (1°), secondary (2°), or tertiary (3°)

phenol

an organic compound in which an -OH group is attached to a carbon atom that is part of an aromatic carbon ring system.

aryl group

An aromatic carbon ring system from which one hydrogen atom has been removed.

Solubility Test

Type of test used to determine the ability of compounds to dissolve in a solvent - usually liquid - at equilibrium. Use these tests to determine the size and polarity of unknown compounds and the presence of acidic and basic functional groups.

KMnO4

Potassium permanganate

Immiscibility

When two substances do not entirely mix and refuse to form a homogeneous solution. Instead, they separate into distinct layers or give rise to a heterogeneous mixture, where each component retains its individual identity.

Miscibility

The remarkable ability of two substances, particularly liquids, to seamlessly mix and form a homogeneous solution.

Solubility

The ability of a solute to dissolve in a solvent.

Ethanol and 2-Propanol are both miscible with Water and Acetone

Because of the same polarity

Ethanol and 2-Propanol are both immiscible with Toluene

Because given that ethanol and 2-Propanol is polar while Toluene is nonpolar making it soluble causing the solvent toluene to dissolve.

Phenol is immiscible to both Water and Acetone

Due to the reason that it is partially polar because of the hydroxyl group in the aromatic ring making it soluble to water and acetone.

Phenol is miscible to Toluene

The presence of the benzene rings in both molecules allows for π-π interactions, which can facilitate some degree of miscibility between them despite the difference in polarity.

π-π interactions

also known as pi-pi interactions or aromatic stacking interactions, refer to non-covalent interactions between the pi electron clouds of aromatic rings. These interactions occur in molecules that contain conjugated double bonds or aromatic rings.