Manual of American grape-growing

by U. P. Hedrick

Over-production, with the attendant losses caused by glutted markets, is a factor which, like frosts and freezes, is ever in the mind of the grape-grower. No season passes but that some of the grape regions of the country suffer from over-production. Not uncommonly the grape industry in a region is better off in a season when the crop is small and prices high, than when the crop is large and prices low. In every part of the country where grapes are grown, over-production has been a great deterrent to viticulture; this, in spite of the fact that grape-growers have availed themselves of the opportunity to manufacture products from this fruit. Thus, wine and raisins are made from the grape in California, and a large part of the harvest in the East goes into wine, champagne and grape-juice. But the growth of prohibition now threatens the wine and champagne industries of the country, in fact may be said to have driven them to the wall, making the need of new outlets in manufactured products a greater necessity.

Under these conditions, grape-growers must seek in every way to enlarge the sale of the crop to manufacturers with the hope that thus, together with more perfect distribution of his commodities, the inroads made by prohibition on the industry may be offset and the over-production of table-grapes be better prevented. With this brief emphasis on the importance of manufactured products of the grape, we approach the discussion of the several possible outlets to over-production in this fruit.

Wine

The manufacture and use of wine in America, as has been intimated, is likely to cease through prohibition. Therefore, whatever may be said of this product of the grape is of less and less interest to grape-growers. However, a few years of grace probably remain for the making of wines in America, and since wine-making yet offers the greatest outlet for the grape crop, next to table-grapes, wine must be considered as a factor in the grape industry.

Since the demand and price for grapes depend very largely on the kind of wine to be made, it is necessary to characterize the wines made in America. Wine, it should be said, is the product of alcoholic fermentation of the grape. Alcoholic fermentations made from other fruits are not, strictly speaking, wines. Natural wines are divided into three broad groups; dry, sweet and sparkling wines. Dry wines are those in which sugar has been eliminated by fermentation; sweet wines those in which sufficient sugar remains to give a sweet taste; and sparkling wines are those which contain sufficient carbonic acid gas to give a pressure of several atmospheres in the bottle. The carbonic acid gas is produced in sparkling wines by fermentation in the bottle of a dry wine.

The color in these three classes of wine may be red or white, depending on whether or not the color is extracted from the skins in the process of fermentation. To make red wine, of course, the grapes to be fermented must have red coloring matter in skin or juice or both. Each of these groups of wine includes a very large number of kinds distinguished by the name of the region, the locality or the name of the vineyard in which a wine is made. Wines are still further distinguished according to the year of the vintage.

Wine-making.

There are four distinct stages in the making of wine after the grapes are grown. The first is the harvesting of the grapes when they have reached the proper stage of maturity, which is known as "wine-making ripeness." This stage of ripeness is determined by means of a must-scale or saccharometer. The wine-maker squeezes the juice from a number of bunches of grapes into a receptacle into which he drops the must-scale, whereupon the sugar-content of the juice is indicated on the scale, determining whether the proper stage of ripeness has been reached. Suitable varieties of grapes having been grown, it is necessary that they be permitted to hang on the vine until the proper degree of ripeness is developed, after which they are delivered at the winery as free as possible from injury or decay.

The second stage is the preparation of the grapes for fermentation. The grapes are weighed on arriving at the winery and are then conveyed either by hand or more often by a mechanical conveyor to the hopper or crusher. The ancient method of crushing, which still prevails in some parts of Europe, was to tramp the grapes with bare feet or wooden shoes. Tramping has been superseded by mechanical crushers which break the skin but do not crush the seeds. The best mechanical crushers consist of two-grooved revolving cylinders. As the grapes pass through the crusher, they fall into the stemmer, a machine which tears off the stems, discharging them at one end, while the seeds, skins, pulp and juice pass through the bottom to the presses usually on the floor below. There are several types of wine-presses, all of which, however, are modifications of screw, hydraulic or knuckle-joint power. In large wineries, the hydraulic press has almost driven out the other two forms of power and when great quantities of grapes must be handled a number of hydraulic presses are usually in operation. The grape pomace is built up into a "cheese" by the use of cloths and racks variously arranged. The "cheese" is then put under heavy pressure from which the juice or "must" is quickly extracted.