Labo VinRacking the wine
Racking consists in separating the wine from the dregs (yeasts and plant bits). Several rackings will be necessary because it is impossible not to suck a little dreg at one time.
Racking is essential because the deposit of yeast and plant bits will progressively break down to bear an unpleasant taste to the wine.
Racking has to be done as quickly as possible.
When cuvage occurs, a preliminary racking is made from the end of this one. For fruit wines, this racking is most often accompanied by a pressing. For leaves, flowers, aromatic herbs, this racking will discard plant organs after flavour extraction. This preliminary racking will not eliminate yeasts that are still suspended in the must. It is often carried out by sieving, but also by siphoning off [ Rack the wine carefully, attending to withdraw as less as possible dregs (a rigid tube is more convenient than a flexible hose directly plunged in the wine). Possibly pinch the hose to avoid a too violent aspiration. Bring in the wine as less air as possible (hold the hose extremity in the bottom of the receiving container. ] .
Next rackings will be made when the alcoholic fermentation stops, when the wine turns well clean due to yeasts sedimentation. They are carried out by siphoning off [ Rack the wine carefully, attending to withdraw as less as possible dregs (a rigid tube is more convenient than a flexible hose directly plunged in the wine). Possibly pinch the hose to avoid a too violent aspiration. Bring in the wine as less air as possible (hold the hose extremity in the bottom of the receiving container. ] .
1) First racking
This racking, the most important, must be carried out soon after the end of the cold clarification, immediately after the clarification refining tests.
Racking eliminates the protecting CO2 layer and reduces the wine volume. The new carboy will be smaller and entirely filled. The level can possibly be raised by introducing big glass marbles or stones, properly cleaned and disinfected, or collect a surplus of wine in smaller containers. The air can also be replaced by CO2 coming from another fermenting carboy, or produced by the following reaction: CaCO3 (65 g) + citric acid (90 g) -> CO2 (30 L).
If the clarification-refining test [ - One or two days before racking, fill with wine 5 100 mL bottles numbered 0, 1, 2, 3 and 4.
- Whip up an egg white with a little water and bring it to 1 litre, integrating the foam.
- Add to the bottles from this solution as many times 1 mL than the number the bottle bears. Close, shake the bottles and place them in a fridge without shaking any more. The racking day, pick out the clearer bottle that is suitably astringent and note its number (the bottle 0 must be the less clear).
If several bottles are clear, choose the bottle being rightly astringent; the egg white has indeed reduced the tannin content.
- Rack the wine, adding to it, for 1 litre, an egg white solution volume matching up to 10 times the chosen bottle number. ] indicates the necessity to add some egg white, add in the new carboy, for 1 litre wine, an egg white solution volume matching up to 10 times the bottle number chosen by the test.
During the racking, when the carboy is half-filled, add 10 mL/10 L metaK [ Solution 0.25 M of potassium metabisulfite (K2S2O5, Mr=222), prepared by dissolving in water 55.5 g potassium metabisulfite (failing which, 47.5 g sodium metabisulfite - Na2S2O5, Mr=190) for 1 L solution.
10 mL of this solution equals 320 mg SO2 (5 millimoles).
This solution can be kept for a long time in a tightly sealed bottle. ] (except if sparkling wine is scheduled).
On the completely filled carboy, place an airlock containing a mixture with equal parts of glycerol and concentred disinfecting solution. Keep the wine in a cool place.
2) Second rackings
There's no need to hurry. The wine, free of dregs, well balanced, protected by SO2, can wait for a long time. Observe the clarification progress either by watching through the carboy, or by withdrawing regularly (every month) a sample and observing it in a wide glass, in the light. The wooden barrels must be regularly "ouillés" [ Ouiller (French verb): to compensate wine evaporation through a cask in order to keep it full. Use a wine excess got in small containers during a preceding racking, or, failing which, an alcohol solution at 15 % vol. ] to compensate the evaporation.
3) Later rackings
Several rackings may be necessary before the wine forms a negligible deposit. When you estimate the wine clear enough, it must be tasted. A lack or an excess of astringency can readily be corrected. A shearing can reduce the fruity taste...