Ripeness

Question 1

Physiological vs Phenolic Ripeness

Answer 1

Physiological:

Phenolic:

Question 2

Managing alcohol levels

Answer 2

AWRI study (Jan 2016): 
     - 40% of Australian consumers and over 50% of Chinese consumers prefer lower alcohol wines, citing heat and bitterness as negatives

HEDGING
- The rate of sugar accumulation largely depends ratio of leaf area to fruit weight. Therefore, hedging and deleafing can slow down sugar accumulation

HARVESTING EARLY
- Also simply harvesting early is an option, a study showed similar consumer preference in Cabernets between 13.6 - 15.5% ABV

WATER ADDS
- In Australia, water added through normal winemaking adds (dissolving bentonite, tartaric, or activating yeast) is capped at 7%, but if that full amount was used, ABV could be lowered by 1%.

ENZYMES
- GOX (glucose oxidase) transforms glucose to gluconic acid and hydrogen peroxide, and when used before fermentation can lower ABV by 0.7%

FERMENTATION MECHANICS
- Some studies indicate that high temp and open top tanks can reduce ABV

YEAST
- AWRI 796 produces a wine with 0.4% less ABV than some commercial yeasts

OTHER TECHNOLOGIES
- reverse osmosis, spinning cone distillation, evaporative perstraction, vaccuum distillation (these are illegal in many places)

EVAPORATION

 - water evaporates faster than ethanol, so a dry cellar will increase ABV
 - humidity of 70% or over will lose more alcohol than water, thereby lowering ABV

BLENDING
- blending low and high alcohol wine