The Wine Press and the Cellar: A Manual for the Wine-Maker and the Cellar-Man

by Emmet H. Rixford

Stirring the Pomace in the Vats.—In Burgundy, and in some other parts of France, it is considered necessary to give the mass a thorough stirring (foulage) during the active fermentation, in order that all parts may be equally exposed to the action of the ferment, and also that a good color may be developed; and for this purpose men enter into the vats and thoroughly mix the pomace and stir it about with their naked bodies and limbs, a practice not only disgusting in the extreme, but dangerous for the men, who are exposed to the poisonous effects of carbonic acid. It is by no means a general practice, and is of doubtful utility, even if it should be done by other agents than the naked human body.

It is evident that two opposing forces are at work when the must is stirred during fermentation. By the aeration fermentation would naturally be increased; but Dr. Guyot shows that stirring actually diminishes its activity, and he advocates the practice in order that the fermentation be not too tumultuous. The temperature of the surrounding atmosphere being lower than that of the fermenting mass, aeration by stirring must, by lowering the temperature, diminish the activity of the fermentation. Mr. Haraszthy, in his lecture before the Convention of Viniculturists in 1882, recommended that the mass be stirred when the fermentation commences to lag, on the theory that by thus mixing again the yeast with the liquid, so exposing it again completely to the action of the ferment, fermentation would start again with renewed vigor. It can easily be stirred with poles provided with shoulders or short cross pieces.

It has already been stated that the must is sufficiently aerated by crushing the grapes with rollers, and where the vats are provided with a false head to keep the pomace submerged, the wine will have sufficient color without the stirring; and it would seem that the wine would clear sooner if the lees were not stirred into it near the end of fermentation. Where the vats are not covered, and the grapes are not stemmed and not kept submerged, a crust or cap is formed on the top of the fermenting mass, which sours and rots if long exposed to the air, and the mixing of this with the liquid has a most deleterious effect upon the wine.

When to Draw from the Vats.—When the first or active fermentation in the vats is completed, the new wine must be drawn off into pipes, and thus be separated from the marc, consisting of skins, seeds, and sometimes stems, and also from the heavy lees which has settled in the vats, and it is important to know the proper time to do this.

The duration of active fermentation depends upon several causes and conditions as already indicated, such as heat, the amount of sugar contained in the must, whether the vats are covered or open, the immersion of the marc, and whether the grapes are stemmed, etc. It may be completed in four or five days, or it may continue for fifteen or twenty days. In case of musts poor in sugar it may rarely terminate in twenty-four hours. In some parts of France the grapes are allowed to macerate for weeks and even months (for they cannot ferment actively for that length of time), and what might be good wine, thus is often spoiled.

The Objections to Long Vatting are that the marc will absorb an undue amount of alcohol, as is shown when it is submitted to distillation in brandy making, for marcs which have remained long in the vats with the wine yield more spirits, and, of course, the wine is deprived of so much strength. This objection, however, would have but little force where the grapes are stemmed. Another and more serious objection is, that by a long exposure to the air which is apt to take place when the vats are not closely covered, some of the alcohol will be changed to vinegar, and the wine will rapidly degenerate, and become sour. Long contact with the seeds, skins and stems also produces a foreign taste in the wine known to the French as goût de râpe, stem flavor; and it is obvious that if the marc is allowed to remain in the liquid till it macerates and rots, it will acquire a still more disagreeable aroma and flavor. It is also said that some varieties of grapes which will not produce a wine with a bouquet, when allowed to remain long in the tank, will develop it in a vatting of short duration. The only advantage to be gained by leaving a wine in the vat after the active fermentation is finished, is in the way of color. When it is desirable—if it ever is—to produce a dark-colored wine at the expense of other good qualities, it may be left in the vat to soak. Such wines have their use, and that is to mix with those which lack color, but it is much better to mix in a quantity of grapes which naturally produce good color.

In making Fine Wines, a dark color is not looked for nor desired, but rather a bright and lively red; and they should be allowed to remain in the vat only long enough to convert the greater part of the sugar into alcohol.

How to Know when to Draw from the Vat.—It is said in general terms that the wine should be drawn from the vat when the active fermentation is finished. This is known by the taste of the wine by those long familiar with the vinous flavor which takes the place of the sweet taste of the sugar; it is also recognized by the cessation of the production of carbonic acid and the consequent bubbling, the falling of the temperature, the settling down of the marc, and by the clearing of the liquid. If the must or new wine shows from 0° to 1° by Baumé’s hydrometer, or from 0° to 2° by Balling’s saccharometer, nearly all the sugar will have been converted into alcohol; I say nearly all, for all the sugar is not converted till long after the wine is drawn from the vat. Boireau says that the fermentation is yet incomplete when the hydrometer marks several degrees of density, and the liquid is warm, sweetish, and muddy. He says, moreover, that care should be taken that active fermentation has entirely ceased before putting the wine in pipes, for if it is still sweetish and fermenting, it will remain sweet a long time, and ferments will often remain in suspension, which will render the wine difficult to clear, and liable to ferment and become sour.

Method of Drawing from Vats and filling Casks.—If the pipes are on the same level with the vat, or higher, the new wine is run from the vat through a faucet into buckets and carried in them to the casks and poured into these through a funnel, or is run into a large receptacle or tub placed immediately under the faucet and pumped into the casks by means of a force pump. But the more expeditious way is to have the casks ranged on a level lower than the bottom of the fermenting tank, and then to run the wine directly into them through a hose attached to the faucet. Of course, careful men must be in attendance to watch the operation, and close the faucet as soon as the cask is filled, and immediately transfer the hose to an empty one, so that the wine may not run over and waste.

Where the wine is drawn from more than one vat, it should be equally distributed through all the casks, so that the quality may be as nearly uniform as possible. If the press wine is to be mixed with the vat wine, the casks should only be filled to three-fourths or four-fifths of their capacity, in order to leave room for the former.