Labo Vin
Free software

• Alcohol

• Sugar

• Acidity

• Winemaking
  • Choosing the fruits
  • Fruit composition
  • Collecting the sap
  • Juicy fruits
  • Fine fruit pastes
  • Fruits poor in juice
  • Tree saps
  • Flowers and leaves
  • Flavoured juices
  • Crushing or foulage
  • Material disinfection
  • SO₂
  • Cuvage or maceration
  • Pressing
  • Correcting the juice
  • Correcting the acidity
  • Correcting the sugar
  • Correcting the nutritive salts
  • Fermentation
  • The malolactic fermentation
  • Choosing the yeast
  • Correcting the wine
  • Racking the wine
  • Bottling
  • Sparkling wine
  • Keeping the wine

• Tables

• Glossary

• Bibliography

Fine fruit pastes or pulpy juices

The presence in the juice of solid plant debris is not desirable; they will decay after a while into noxious substances (fusel oil [ The fusel oil is a mixture of several superior alcohols (amyl, isoamyl...) produced by the yeasts metabolism. In large amount, the fusel oil is toxic and negatively modifies the wine savour. The amount of produced fusel oil essentially depends on the used yeast strain and its culture conditions. Thereby the wild yeasts (apiculate yeasts) produce large amounts of fusel oil, as well as yeasts cultivated in bad conditions (yeasts suffering due to lack of nutritive salts, excessive temperature...). ] ). However it is often impossible to straight off separate the pulp from the juice, either because the paste is so thin that the cheesecloth cannot retain the pulp, or because the cuvage would be too long for the extraction of the substances of interest.

In that case, you will directly carry out a fermentation-cuvage on the fruit paste. The resulting alcohol will favour the extraction. Berries, flowers, leaves will be, for the same reason, processed in the same way, like also the aromatized juices.

The winemaking from pulpy saps and related will be carried out in two steps

1. At the outset, roughly correct acidity and density on a juice sample separated on the cuff from the pulp after a few hours. One evaluate the volume of sap the paste will give, deeming that the pulp will retain neither sugar nor acid and that 70% sap will remain after filtration.
   Adjust the potential alcohol to less than 8%; add pectinase [ The pectinase is an enzyme (protein, biological catalyst) that destroys the pectin. It follows a better flavours extraction, a better sap yield, along with a good ulterior clarification. The pectinase is sold as a liquid or a powder. Conform to the manufacturers instructions. Too much pectinase is not damaging, but it is wasting. ] , nutritive salts then yeast.
2. When the fermentation stops (4-6 days), still wait for one day, then strongly shake the must, filter it through a colander, measure and correct this clear sap for acidity. Sample the sap that must be dry. Measure the alcohol rate with a vinometer. Adding sugar, adjust the final alcohol rate you wish. Wash the fermentation container and fill it up with clear wine, after measuring the volume.
   The fermentation starts again and the next steps are like juicy fruits. If the filtration is not perfect, rack the wine at the end of the second fermentation.

 

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