PART VI.
VEGETABLES, CONDIMENTS, FRUITS.
SUCCULENT VEGETABLES.
The term vegetable as applied to food in the broadest sense of the word means that class which distinguishes it from animal food. In a narrower sense, however, the term vegetable is used to denote a certain class of food which is of a succulent or juicy nature. While cereals and fruits are vegetables in the broadest sense of the word they are not in the narrow and common meaning. The term “vegetable” in this section therefore refers to those substances commonly known as vegetables upon the market and which are characterized by their high water content. On account of this abundance of liquid or juice the term succulent is applied to them. The common vegetables which are included in this class consist of lettuce, spinach, potatoes, cauliflower, beets, radishes, turnips, cabbage, green Indian corn, peas, beans, tomatoes, yams, etc. These vegetables contain in a fresh state from 70 to 95 percent of water. Many of them can be kept for a length of time without deterioration, especially the potato and beet, and for a short time cabbage, radishes, etc., if kept cool and moist. Other kinds of vegetables are not easily preserved for any length of lime except in cold storage, such as lettuce, peas, beans, tomatoes, etc. If the potato and other starchy tubers are kept out of account these vegetables do not have a very high nutritive value, as will be seen by the analysis which follows. They have, however, an important part in the ration because of their palatability and the effect which they have upon the general activity of the alimentary canal. For instance, there is very little nourishment obtained in eating a turnip which perhaps is 95 percent water,—yet its palatability, its condimental character, and its general salutary effect upon digestion is such as to make it worth while to pay even a high price in proportion to its nutriment. For this reason, as well as for their nutritive value, the use of succulent vegetables is to be very highly commended.
In general, as has been said, these vegetables are eaten in a fresh state or after being kept for a considerable time in cold storage or otherwise. The potato, for instance, can be kept by properly covering it in the earth or in bins through the winter. Cabbages are also kept in the same way and many other vegetables without apparent deterioration. These vegetables are often desiccated, and in this way can be kept for a much longer period. Unfortunately no method of desiccation has been developed which preserves entirely the palatability of the vegetable, although its nutrient properties, which are perhaps the least important of its properties in many respects, are preserved to a certain extent by desiccation.
We may, however, leave out of consideration the desiccation of fresh vegetables. Certain of the vegetables above mentioned naturally become desiccated on maturity as in the case of peas and beans, but then they are removed from the category of succulent vegetables. Green Indian corn is also often dried, but in this process its palatability is to a certain extent impaired even when it is prepared for cooking in such a way as to restore practically all of the water which has been lost. Succulent vegetables are eaten either in a raw state or after cooking. For instance radishes and vegetables of this class are rarely cooked. On the other hand, potatoes, peas, and beans are always cooked and practically never eaten raw. Green Indian corn is also universally cooked before eating. There are other vegetables which are sometimes eaten raw and sometimes cooked, as, for instance, the turnip, while on the other hand the beet, which is very sweet and naturally would be considered a suitable food for eating in a raw state, is always cooked before it is consumed.
Artichoke.
—This vegetable, while not very extensively grown in the United States, is cultivated to a very extensive degree in Europe. The tubers of the artichoke (Cynara Scolymus) are essentially a carbohydrate food, growing underground, and thus belong, in a measure, to the same class as the potato, the yam, and the beet. The carbohydrates which are present in artichokes do not contain very much starch. In this respect they differ from the potato and the yam. When the starch of the potato and yam is converted by fermentation or otherwise into sugar it forms chiefly dextrose or maltose. On the other hand, when the carbohydrates of artichokes are converted into sugar they form chiefly levulose. The principal part of the carbohydrate is known as inulin or levulin. The artichoke can be easily kept over a long period of time, and may remain without much detriment in the ground, where the winters are not severe, from autumn until spring. After harvesting it may be kept for some time without any very great loss in its food value.
In the following table are given the data showing the composition of the artichoke, harvested in the autumn and also in the spring:
| Spring: | ||
| Water, | 79.03 | percent |
| Inulin or levulin, | 17.76 | „ |
| Protein, | 1.27 | „ |
| Ether extract, | .18 | „ |
| Ash, | .99 | „ |
| Fall: | ||
| Water, | 79.70 | percent |
| Inulin or levulin, | 16.93 | „ |
| Protein, | 1.48 | „ |
| Ether extract, | .14 | „ |
| Ash, | 1.08 | „ |
| (Behrend, J. für Landwirtschaft, vol. 52, p. 134, 1904.) | ||
The above data show that the artichoke, like the potato, is a food product poor in protein and in fat and rich in carbohydrate material. In so far as known the carbohydrates of artichokes are equally as digestible and nutritious as those of other tubers.