The Raisin Industry / A practical treatise on the raisin grapes, their history, culture and curing

by Gustavus A. Eisen

There are several ways of stacking. The flat-stacking is used principally when the raisins are very dry, and when it is of importance that no air should enter the trays. In flat-stacking, one tray is simply placed on the top of the other, and the circulation of air thus brought to a minimum. In rainy weather, however, the roof-stacking is to be preferred. Instead of placing one tray on the top of another, the trays are placed in two piles joining each other in such a way that the inner end of every tray overlaps the edge of the tray in the adjoining pile. This lifting up of one edge of the tray gives to the whole pile a roof-like appearance, and the angle in which the trays join together becomes steeper the higher the pile grows, until, at the height of three or four feet, the trays slant so much that the raisins cannot rest on them, but are in danger of sliding off, when, of course, the pile should not be made any higher. It takes several times longer to stack the trays in roof fashion than to simply pile them up flat. The advantage of roof-stacking is that it admits more air, and sheds the rain better. In damp weather the piles should not be covered on the sides for any length of time, as the raisins will then mold more rapidly. If, instead of joining two piles of trays, three piles are made to join, the center stack will be flat, while much air is admitted to the raisins. In this stacking the first two trays are placed flat on the ground at almost the distance of one tray. Another tray is made to rest on the inner edge of the lower trays and cover the intermediate space, and so on. This method gives twice as much air space between the trays as regular flat-stacking, and is to be recommended when the weather is damp. A combination of this last method and roof-stacking is used by some, every grower almost having his favorite way to stack. It must be remembered that in very rainy weather no kind of stacking will be of any value, while, when the showers are few and far between, stacking may save the crop.

Stacking is especially valuable in conjunction with dryers, when protection during a few days only is all that is needed. One man can stack about five hundred trays an hour, and the regular picking gang can stack a whole vineyard in a few hours. Should the rain be very heavy and no dryer handy, it is of no use to try to save the crop after the mold has begun to make its appearance, and when the berries have begun to rot. It is then far better to dump the whole crop in the field rather than to spend time, money and anxiety on raisins which must in any case become a total loss.

Taking Up.

—When, at last, the raisins are sufficiently dried, they must be taken up as quickly as possible. This process again consists of three different labors,—the stacking, assorting and boxing. It is of great importance to know exactly when the raisins have sufficiently dried to be ready for the sweatboxes. This can properly only be ascertained by experience, still a few directions will materially help the inexperienced grower in his judgment. A perfect raisin should be neither too hard nor too soft. A raisin is too soft when, after rolling it between the fingers, the least particle of juice exudes through the cracked skin or meat. Such raisins will “sugar” in course of time, and not keep a year. If the raisins, or a majority of them, on a bunch are too wet, they should be spread to the sun for some time longer. If, however, there are only a few underdried raisins in a bunch, the bunch may be taken in, and the soft raisins clipped off afterwards. A raisin is too dry when, in pressing and rolling it between two fingers, the pulp does not move readily inside the skin. Such overdried raisins will not again become first-class raisins; their skin will always be tough, and their color will be somewhat inferior. If but slightly overdried, they may be brought out by equalizing. To know when the raisins are in a proper condition to take up is most important to every raisin-man, and he should never neglect to watch his trays early and late. Upon his good judgment and watchfulness depend the quality of his crop. To prevent too rapid drying out after the raisins are nearly ready, the practice now is to stack the trays in the field.

This stacking simply consists in placing the trays which contain the ready raisins on top of each other, in piles five feet high. On the top of every such pile are placed several loose trays crosswise, so as to shelter the pile from the sun, and possibly even from rain, and other trays are raised up against the sides of the pile in order to exclude as much air as possible. If, however, the raisins are rather underdried, the side trays may be left out so as to allow the raisins to dry more. It is always best to stack the trays before the raisins are fully dried, as they will finish drying and curing in the stack much better than in the sun. The underdried raisins will thus dry just enough, while the overdried ones, or those just right, will not dry much more.

After the stacking is done, the assorting is in order. This consists in taking out every bunch that is not sufficiently dried to go into the sweatbox, and placing them on new trays to dry more. At this time, also, the bad or inferior and red berries may be taken out, if present in a very large quantity on good bunches; but when there are only a few on, it is better not to touch the bunch, as, in handling it, it is only too apt to break. Any further picking out of bad berries had better be deferred to the packing-house. The boxing and assorting, which may be considered together, consist in transferring the different grades of the now dried raisins to separate sweatboxes. This is done in two ways. The number one bunches, which have been placed on separate trays, may now simply be slid into the sweatbox, by a dexterous movement of the tray. Between every two layers of these first-class bunches should be placed a stout manilla paper cut so as to exactly fit the box. It is of importance to have the paper just fit the box, and not be too large nor too small, as in either case the raisins are apt to become mixed and the bunches broken. But, if the grapes have not been assorted from the beginning on separate trays, more work will be required to get them into the sweatboxes. Every bunch must be carefully taken up by hand from the tray, and then placed on the paper in the box. But in doing so many bunches are necessarily broken, as even careful hands cannot help frequent mishaps, while ignorant and careless workmen may do an immense injury to the crop. Too few manilla papers are generally used. Some packers require only two papers in every box, while six or eight, or at least five, papers should be the proper number for every box of very choice or even ordinary layers. We must remember that, the more papers we use, the less apt are the bunches to be injured, but even the best layer bunches will not suffer if placed two layers high between every paper. On top and in the bottom of every box must be one paper, so as to keep out dust. The loose and inferior raisins, which either have been left on the tray after the layers are picked out, or which from the beginning have been placed on separate trays, may now, when perfectly dry, be simply dumped in sweatboxes without any paper.

We have thus at least two kinds of sweatboxes. One kind contains those raisins which are destined to make layers, and which require sweating and equalizing before they can be packed. The other kind contains the loose and drier berries, which are to go immediately to the stemmer and grader, and which would not separate from the stems if they were made to equalize.

Covering.

—If the weather has been favorable, the raisins may have been dried and cured in twelve days. Of these twelve days, the first seven or eight were used for drying the upper side of the raisins. On the seventh or eighth day they were turned, and on the twelfth day they were ready to put in the sweatboxes. But this is fast drying, and drying under favorable circumstances, with a dry wind blowing gently all the time. But sometimes it takes a much longer time to dry, say from fourteen to twenty-one days. In Fresno, where the weather is less favorable, the drying of the first crop may require from two to three weeks. In El Cajon it always takes two or three weeks for the raisins to dry, and in Orange county the drying sometimes requires from thirty days to five weeks. In Malaga the drying is accomplished quicker than in California, because there they cover the raisin floors every night with canvas, and in the morning, when the canvas is unrolled, the raisins are yet warm. The drying, then, has been continued all night, and the raisins have not had time to cool when they meet the first rays of the sun. In California, again, our raisins are cold, possibly even wet with dew or rain, and it sometimes takes the sun until noon to dry up the moisture accumulated through the night.

To counteract this absorption of moisture, many of the raisin-growers in Orange county, California, especially around Santa Ana and McPherson, cover the trays with canvas every night. This method is to be recommended wherever there is any difficulty in curing either the first or the second crop. If this method is employed, I am satisfied that raisins could be grown and properly cured in localities where otherwise no raisin cult is possible. The method of covering the raisin trays at Santa Ana is as follows, varied by different growers, but in the main the same everywhere. The trays are placed together in long rows; about twenty yards long is found to be most convenient. The width of the row is just the width of two trays, or five feet. Thus the row of trays laden with raisin grapes is about sixty feet long by five feet wide. Along the north end of this long row of trays are driven down small posts every six or ten feet, and left extending about two feet above the ground. Along the south side of the row of trays smaller posts are driven down at the same distances, but not allowed to extend so high above the surface of the soil. These pegs or small posts may best be slanting outward, or from the trays. Along the high posts is strung a wire in such a way that it cannot easily get loose. To a long canvas cover are now secured small rings for running on the wire, and on the other side larger rings to hook over the smaller posts in front. If the canvas is only one yard wide, two widths must be sewed together so as to make the canvas six feet wide. The trays, which are two and one-half feet by three feet, when placed side by side will just form a drying floor of five feet, large enough to be covered by the canvas six feet wide. The cost of canvas is six and one-half cents a yard by the bale.