Red wines are made from colored grapes, and the color is extracted from the skins during fermentation. The coloring matter is blue, but is changed to red by the action of the acids in the must. (See Coloring Matter—Oenocyanine.) In order to develop this color, the grapes are fermented, skins and juice together, and the press is only brought into requisition after the first fermentation is completed.

Fermenting Tanks or Vats.—The tanks or vats in which red wine is fermented, in France are generally made of oak, sometimes of masonry, but in this State redwood has been almost universally adopted, and I am not aware of any serious inconveniences from its use. It is advisable before using them the first time, to steam them for several hours, or thoroughly soak them to extract the coloring matter of the wood.

The capacity depends upon the quantity of wine to be made in a season, varying from 1000 gallons to 2500 gallons and more, and a sufficient number should be provided that when wine making has commenced, it can be carried on without interruption till the crop is worked up. The number of workmen must be considered as well as the amount of grapes, and everything ought to be so arranged that the fermentation will be finished in the first tank filled, by the time the last one is full, so that the first can be emptied and filled again, and then the second, and so on. A hole must be bored in each vat two or three inches from the bottom by which to draw the wine through a faucet. And some kind of a strainer must be put over this hole inside to keep back the marc—a piece of perforated tin, a grating of small sticks, or a bundle of straw or vine cuttings kept in place by a stone.

Filling the Tanks.—In order that the whole mass in one tank may be equally fermented, it should receive its full complement of grapes in one day. By putting in part of the grapes one day and part another, not only will some of them complete their fermentation before the others, but the addition of fresh grapes to the fermenting mass will interrupt the fermentation, and prove injurious to the wine. The vats must not be filled to their full capacity, for during violent fermentation the marc, consisting of skins and seeds, or those with the stems, rises to the top, brought up by the bubbles of carbonic acid which are constantly rising, and a portion of the boiling and foaming mass may be carried over the top, and much wine thereby be lost. They should only be filled to within a foot or a foot and a half of the top, and a little experience will show the proper practice. Guyot says that they should only be filled to five-sixths of their capacity at most. Another reason for not filling the tank is that a layer of carbonic acid gas will occupy the space left vacant by the pomace, and prevent the contact of the air and the consequent souring of the wine, by the changing of a portion of the alcohol into acetic acid—vinegar.

Red wine is fermented in open vats, vats loosely covered, or in vats hermetically sealed, and good wine is made in each way.

In Open Vats, other conditions being equally favorable, fermentation commences more promptly and is sooner ended, owing to the free access of the air, a certain amount of oxygen, as already shown, being necessary to fermentation. Although fermentation will continue away from the air when once started, it will be slow. The objections to open vats are, that although there is a layer of carbonic acid resting above the must, yet it is liable to be disturbed and become mixed with the air, and if the fermentation is long continued, a portion of the wine may become sour. Those who employ open tanks should also avail themselves of those conditions under which the wine will complete its fermentation in a few days, and should draw off promptly.

Closed Vats.—By using closed vats fermentation will be longer in commencing, and will proceed more slowly, but as already intimated, the wine can with safety be left longer in them than in open tanks. When it is necessary to develop much color, it would be advisable to use covered tanks, for the longer the wine is left in contact with the skins, the darker it becomes. The covering should be close enough to prevent the immediate contact of the open air, and yet allow the escape of gas—of close boards, but not luted, unless provided with a safety valve.

The Best Practice, however, in all cases, whether the vats are closed or not, is to have a false head resting directly upon the pomace, and which will keep the latter submerged during the whole process of fermentation. In this way good color will be developed, and the marc will be kept from the air, and the danger of souring will be avoided. In figure 5, A represents a fermenting vat with the front half removed, showing the false head in place.

This head is made of several pieces which can be laid one by one upon the pomace, and maybe perforated with auger holes as represented in C, or may be a wooden grating, D. These pieces or sections together constitute the head B, and are kept in place by two cross pieces, e e, which are held down by blocks bolted or pinned to the inside of the tank. G is a stave with a block, f, attached, and H the same, showing the cross piece, e, slipped under it. When the tank is filled to the required height, the false head is put in, resting on the pomace, the ends of the cross pieces are slipped under the blocks, and everything is ready. As soon as the fermentation becomes violent, the whole will be submerged in the bubbling wine.

Hermetically Sealed Tanks.—Closely covered tanks must be provided with a safety valve or pipe for the discharge of carbonic acid gas, leading and discharging into a vessel of water, which completely prevents contact with the air. Under pressure the fermentation is much slower, and is not so complete. Yet great advantages are claimed for this method by some writers who maintain that by keeping the cover cool with wet straw or cloth, or by using a safety tube in the form of a worm passing through a condenser on the top of the vat, the vapors are condensed and fall back into the liquid, preventing loss of alcohol, and increasing the aroma, and that the wine acquires a superior fineness and velvety smoothness under the pressure of the gas. Boireau says that this latter quality is caused by the complete dissolution of the mucilaginous matters; and Pasteur has shown that more glycerine is produced when the fermentation is slow, which may contribute to the mellowness and smoothness.

Practice in the Médoc.—Mr. Boireau says that the greater part of the grand red wines of the Médoc, the prime St. Emilion, and the prime Graves, are fermented in closed vats; though a certain number of the viniculturists still follow the old custom, and make their wine in open vats.

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.

Wine Presses.—Wine presses are constructed in several different forms, and the force is applied by means of a simple lever, consisting of a long timber weighted at the end and rigged with a rope and pulley to raise and lower it, or by means of a large screw. Hydraulic presses are also used in large establishments. It is not necessary here to give a detailed description of a press of either kind, for the prospective wine maker will examine the different ones and see them in action, and choose according to his means and necessities. Fig. 6 represents screw presses. A very simple one, however, and which can be made by any carpenter, consists of a box two or three feet square, and a foot or more high. This box, however, is made up of sections, each of which is five or six inches high; and they should be constructed of strong two-inch timber, well mortised together, and perforated with small holes through which the wine may ooze out. The height, and consequently the capacity of the box or receptacle will depend upon the number of sections used. A broad board constitutes the bottom of the press and should be larger than the receptacle itself, and be provided with a rim open in the middle of the lower side, and having a shallow spout for the wine to run through. This bottom is firmly placed so as to incline slightly forward, the sections are placed on it, one on the other, till the box is of the desired height, then the marc from the vat is filled in and a head or follower fitted to the inside of the box is placed on the marc, and pressure is applied with a lever. This lever is a strong piece of timber with its fulcrum end placed in a mortise in a large tree, or adjusted in any other suitable manner, allowing free play to the other end to which is attached the rope and pulley to facilitate its movement.

Pressing and Press Wine.—In the manufacture of all but fine wines, it is the usual practice to mix the press wine with the wine from the vat. And as the wine remaining in the pomace is about one-fourth of the whole, it will be equally distributed among all the casks by filling with it the vacancy left in them. If a light pressure is first applied, the wine of the first pressing will differ but little from the vat wine. After this, however, the marc should be spaded and stirred and pressure applied again, and the process repeated till the wine no longer flows. During the last pressing it is necessary to apply so much force that a great amount of coloring matter is pressed from the skins, and tannin from the seeds, and also from the stems when not removed, and the advantage of color may be more than counterbalanced by the excess of tannin. There may be danger of giving the wine too much astringency by mixing the last pressings.

Special Practice for Fine Wines.—Mr. Boireau indicates the practice in making common wines, as follows, as a warning to those who can make fine wines. He says that the wine which the marc contains is removed by pressing it almost to dryness, and that the wine thus obtained is very muddy, very harsh, and sometimes sour, particularly when the upper part of the crust has not been removed, where open vats are used and the marc not submerged. The greater part of the proprietors of the ordinary growths have the deplorable habit of mixing the press wine, without clearing it, with the limpid part drawn from the vat. He says that it should be kept separate, or otherwise the better part of the wine will be made muddy and difficult to clear.

TREATMENT OF RED WINE.

Insensible Fermentation.—After the wine has undergone its active fermentation, has been drawn from the vat and been filled into casks, the latter should be at once stored in a suitable place above ground of even, moderate temperature, or in an underground cellar whose temperature is not much below 60° F. The new wine still contains some sugar, and a slow fermentation goes on, bubbles of gas are given off, and sediment falls to the bottom. This is called the secondary or insensible fermentation, and when this is finished and no more gas arises, the wine has become clear. A good deal of the carbonic acid that rises in bubbles is not produced by the insensible fermentation, but has become dissolved in the wine during the active fermentation, and is gradually given off with the new gas produced. While the gas is produced in the cask, it must not be closely bunged, but the bung-holes should be loosely covered with a vine leaf, a block, an inverted bung, or a bag of sand, so that the gas may escape. Various patent bungs have been devised with the same object.

The wine should be tasted at each filling of the cask during this period to ascertain whether the insensible fermentation has entirely ceased, which may be known from the fact that it has lost the peculiar pungent flavor of the carbonic acid. As soon as this fermentation is ended, the casks should be tightly bunged with conical bungs, which can be easily removed during the period when it is necessary to fill up frequently.

Ulling or Filling Up.—Owing to the escape of gas and to evaporation, vacant spaces are rapidly formed in the casks which must be filled with the same kind of wine as that contained in them. It is well to keep a certain amount of the wine of each vintage in smaller vessels, to be used for this purpose, such as barrels, kegs, demijohns, and bottles, according to the extent of the vintage. If one vessel is partly emptied, the remaining wine should be put into a smaller one. It is absolutely necessary that all of the casks be kept full or the wine will spoil. (See exceptions under Sweet Wine.) For this purpose, during the first week they should be filled every day or two, then two or three times the next week, and later, once a week, once in two weeks, and finally once a month. This is governed a good deal by the rapidity of the evaporation, which depends upon the cellar or place of storage. This operation is performed by means of any vessel with which the wine can easily be poured into the bung-hole; the convenient utensil, however, is a vessel in the form of a small watering pot with a long spout, with which the bung can easily be reached. (Figs. 7 and 8.) A good substitute is an ordinary tin funnel with a flexible rubber tube attached to the small opening. Where the casks are piled up in the cellar so that the bungs cannot otherwise be reached, a funnel called the Z funnel (fig. 9) is used, which is provided with a long spout or tube turning at right angles to the upper part, and whose tip turns down, and which can easily be passed between the casks to the bung. If, however, the bung cannot be reached, a small hole is bored in the upper part of the head of the cask, and the wine put in with a Z funnel whose tube turns at right angles but does not turn down at the tip (fig. 10.) The vent is opened in the highest part of the bulge, and wine is poured into the funnel whose tip is in the end hole till it rises to the vent, which is then closed, and the funnel is removed and the hole closed.

As some wine is liable to be lost in ulling a cask whose bung is out of sight, to avoid this, an instrument in the form of a watering pot, similar to figs. 7 and 8, has been devised, but whose top is entirely covered, the wine being poured into it through a tube which is closed with a cork when in use. The vent is near the tip of the spout on the under side, so that the wine will run as long as the cask is not full, but will stop as soon as the vent is covered by the wine rising in the cask. It is convenient to have a stopcock on the spout.

Many of these implements are provided with a socket to hold a candle.

Summary of the Rules for the Treatment of New Red Wines.

If the wines are bright, avoid fining, and so preserve their fruity flavor; but if they remain muddy after the second racking, fine them after the third drawing off with the whites of eggs, and leave them the shortest possible time on the finings.

Mr. Boireau says that by such treatment wines will be obtained limpid and free from secondary fermentations, and that grand wines will so preserve their fruity flavor; while if they are allowed to work again after the cessation of the insensible fermentation, they will lose their fruity flavor and mellowness, and become too dry. In order to avoid this dryness produced by secondary fermentations, which will considerably diminish the value of the wines, and especially of grand wines, some wine makers place the casks with the bung on one side after the June racking; this practice should not be followed, for the elevation of the temperature at that season is liable to set them fermenting.

The idea is in all cases to avoid mixing the lees with the wine, and if young wines are to be shipped before the arrival of the period of the first racking, they should nevertheless be carefully drawn off, if they have already become clear, for to mingle again the lees with wine, predisposes it to secondary fermentations, and renders it difficult to clarify.

Treatment of Old Red Wines.—Wines after the fourth racking are treated as old wines. When they have acquired a clean taste, are limpid and no longer ferment, the casks should be carefully filled and tightly bunged, and they should be stored in a suitable place, with the bung turned to one side. The bung being thus constantly wet swells and exactly fills the hole, the wine keeps better, there is less loss by evaporation, and constant filling up is avoided.

If it happens that by bad treatment the wines are not clear and behave badly, they should receive the necessary treatment, and be clarified before permanently put away with the bung at the side.

In cellars and other well closed places, old red wine, clean-tasting, bright and quiet, stored in good, well hooped casks, need only two rackings per year, one in March and the other in September, unless for some reason it loses its limpidity by entering again into fermentation, which will be discovered by tasting from time to time. In that case, it should immediately be drawn off without regard to the date of the former racking, and then fined.

Care should be taken not to leave ullage in the cask of old wine, by frequent samplings and tastings. And when it occurs, in order to avoid its effects, the wine may immediately be drawn into a smaller cask, and this is necessary more frequently in airy storehouses where the evaporation is greater than in cellars.

Boireau says that if these rules are carefully observed the wines will improve, and develop all the qualities which by their nature they are susceptible of acquiring. The greater or less degree of fineness which they acquire by aging under proper conditions results principally from two causes: The first is the deposit of coloring matter and divers salts which the new wine contains in dissolution, and which become insoluble by entering into new combinations, and which in their turn are removed at each racking, with the lees; the second cause is the transformation of the tannin, which gives the wine a certain degree of roughness, into gallic acid, and its extraction in the insoluble combinations which it forms with the different principles contained in the wine and with the finings which are introduced. It follows that old wine loses part of its color and soluble salts, and a great part of the tannin which it originally contained. Its taste is more delicate, its flavor, which was masked by these different matters, comes out better, its bouquet commences to develop, and its mellowness is more pronounced.

These remarks are more particularly applicable to grand wines, for in many of the ordinary ones the fruity flavor which they have when new is lost before the end of the first year, because the mucilages and pectine, which give them their mellowness, are either precipitated with the lees or are destroyed by insensible fermentation. In general these wines lack firmness, body and tannin, and many of them show a strong tendency to lose their color.

The time necessary for wines to remain in wood in order to acquire the highest degree of perfection which they can acquire in casks, depends upon the quality of the wine; wines of strength and body require more time than feeble ones.

Our author says that, on the average, the poorest wines of the Médoc become bright about the end of two years, and if they are kept longer, they lose their mellowness. But on the other hand, the firm and full-bodied wines of the same localities require to remain in wood a year longer to arrive at perfect maturity. Certain wines strongly charged with tannin, coming from certain localities, and those made from the verdot grape, are long in developing, but they keep so much the longer.

When they have attained their entire development and the separation of the lees is complete, they must be bottled, for they will lose their qualities if left in casks. In bottles they arrive at perfection; they acquire bouquet while they preserve their mellowness, but in casks, they finally lose their fruity flavor and velvety smoothness, and become dry.

And he gives the following:

Summary of Rules for the Care of Old Red Wines.

Thus will they acquire all the qualities of which by their nature they are susceptible.

But if they are kept in places to which the air has free access, the evaporation will be great; and if the casks are left with ullage caused by too frequent sampling, or too infrequent racking, they will work, become dry, lose their mellowness, and become slightly affected by acetic acid, produced by contact with the air.