Enology Review

Question 1

tannins

Answer 1

naturally occurring compounds able to interact with proteins and other organic molecules

Question 2

covalent bond

Answer 2

strong chemical bonds where electrons are shared between atoms; occurs in polymerization to create chain structure

Question 3

condensed tannin

Answer 3

polymers of flavan-3-ol units; functions as defense mechanism due to astringent taste and ability to bind to proteins (less digestible), antioxidant

Question 4

esterification

Answer 4

chemical reaction in which an organic acid (carboxylic acid) reacts with an alcohol; carboxylic acid + alcohol = ester + water

Question 5

polyphenol oxidase (PPO)

Answer 5

enzyme that catalyzes oxidation of phenolic compounds in presence of oxygen, leading to brown pigments

Question 6

o-quinone

Answer 6

oxidizing compound; chemical compound formed during oxidation of phenolic compounds

Question 7

glutathione

Answer 7

blocks o-quinone with help of s-compounds; composed of cysteine, glutamic acid, glycine; increases from veraison to harvest then decreases in must during pre-fermentation