13.5 General Winemaking Options: Must Adjustments Flashcards
What is the aim of making must adjustments?
create a more balanced wine
- especially if there has been a compromise in achieving optimum ripeness of sugars, acids, tannins, and flavours
In cooler climates, what type of must adjustments are comon?
- deacidification
- enrichment
What is does the term ‘enrichment’ refer to in the EU?
- adding dry sugar, grape must, grape concentrate, or rectified concentrated grape must (RCGM – manufactured, flavourless syrup from grapes)
- process of concentration (reverse osmosis, vacuum extraction, chilling)
What is chaptalisation? With whom is the practice associated?
- common practice of adding dry sugar to must
- increases alcoholic content of final wine
- Jean-Antoine Chaptal
In chaptalisation, what types of sugar can be used?
beet or cane sugar
What are the chaptalisation rules in the EU?
- Cooler regions: allowed within limits
- Warmer regions: not permitted to add sugar, but can add grape concentrate or RCGM within limits
What is RCGM?
manufactured, flavourless syrup from grapes
For the coolest zones of Europe, what is the minimum natural potential alcohol? What is the maximum enrichment permitted? What is the maximum abc of the final wine for whites? Reds?
Example: Germany (excluding Baden) and UK
- Min natural potential alc: 8%
- Max enrichment: +3%
- Max alcohol final wine (if enriched): 11.5% (12% for red)
For the warmest zones of Europe, what is the minimum natural potential alcohol? What is the maximum enrichment permitted? What is the maximum abv of the final wine (if enriched)?
Example: Most of Portugal, southern Spain, parts of southern Italy and Greece
- Min natural potential alc: 9%
- Max enrichment: +1.5%
- Max alcohol final wine (if enriched): 13.5%
When is sugar added for chaptalisation?
When fermentation is underway because the yeasts are already active and can therefore cope better with the additional sugar in the must
What are 3 other ways of increasing sugar levels that involve removing water from the must? Which are most costly? What is the downside?
- reverse osmosis (costly)
- vacuum evaporation (costly)
- cryoextraction
- Less final wine to sell
What is cryoextraction?
Freezing the must, or even the final wine, and removing ice from it
What might be done in warm or hot regions to lower the potential alcohol of the wine? What is the downside?
- Adding water to the grape must
- Dilutes the grapes’ aromas/flavours and acids
In what types of climates is acidification necessary?
Warm climates without any cooling influences where the malic acid in grapes tends drops dramatically as the grapes ripen
Why might acidification be necessary in warmer climates?
- Malic acid in grapes tends drops dramatically as the grapes ripen
- Final wine could lack freshness
Why might one use acidification?
- Add freshness to warm climate wines that lack enough natural malic acid
- Lower the pH
For what types of wines is acidification used?
All - Inexpensive and mid-priced wines and many premium wines
How is acidification typically carried out?
the addition of tartaric acid, the acid characteristic of grapes
What are other less likely options for acidification? What are the results of each?
The addition of
- citric acid (not permitted in the EU)
- malic acid (less used as it could be turned into lactic acid by malolactic conversion)
- lactic acid (may be used if adjustments need to be made after malolactic conversion; it tends to taste less harsh than the other acids)
When can acidification take place? When is the preferred time?
- Before, during or after fermentation
- Preferred: Pre-fermentation starts
1. benefit from the effects of a lower pH
2. integrates better within the profile of the wine as a whole
What factor is at play when determining how much acid to add?
Total acidity and pH are affected during winemaking, including malolactic conversion and tartrate stabilisation
In the EU, how is acidification regulated?
Controlled within the bands of countries organised according to climate
- In the coolest zone, only deacidification is allowed
- In the warmest zone, acidification is allowed
In the coolest zones of Europe, how much acidification is allowed? Give an example.
−1 to 0 g/l expressed as tartaric acid
Example: Germany (excluding Baden), UK
In the warmest zones of Europe, how much acidification is allowed? Give an example.
0 to +2.5 g/l expressed as tartaric acid
Example: Most of Portugal, southern Spain, parts southern Italy and Greece
In the moderate climate zones of Europe, how much acidification is allowed? Give an example.
- Winemakers can deacidify or acidify according to the season (−1 to +2.5 g/l)
Example: Bordeaux, Spain’s cool north Atlantic coast and Italy’s Trentino-Alto Adige
Can winemakers chaptalize and acidify?
Not permitted in the EU
Where might deacidification be common?
In cool climates where grapes may have to be picked before they are fully ripe (e.g. due to the threat of poor weather)
What are 2 methods of deacidification?
- Adding calcium carbonate (chalk) or potassium carbonate: lowers acidity by the formation and precipitation of tartrates
- Ion exchange: requires considerable investment or hiring expensive machinery, may not be legal
