Food - Vegetable Oils
( Originally Published 1917 )
An important food element. Oils and fats form one of the most important parts of our food. Many of these, such as butter and fat meats, are obtained from animals, but many others come from vegetable products. These last, because less expensive than animal fats and oils, are becoming more and more important as a part of our daily diet.
Chief among the fruits and seeds that yield edible oils are olives, peanuts and other nuts, corn, and the soy bean.
Olive oil. There are a great many varieties of olives. Those used for the purpose of making olive oil are produced chiefly in Italy, France, Spain, and California.
If your father's apple or pear trees were to bear only every second year he would be greatly disappointed. Yet this is all that the growers of the olive can expect. The fruit comes but once every two years. The tree flowers in the spring and the fruit appears toward the end of July. The olive is green until it attains full size. Then as it ripens it gradually turns from green to yellow, and by November, when the harvest begins, it is a rich purplish brown. The picking lasts until spring, although the best oil is said to be secured from the olives gathered in January and February.
After being picked, the olives, in order to make the fruit give up its oil more readily, are spread out and slightly heated for about twenty hours. Next they are ground into a pasty mass which is subjected to heavy pressure until all the oil is extracted.
The use of olive oil as a food is rapidly increasing in this country. It is over thirty times as nourishing as beef soup and twenty times as nourishing as milk. It is generally superior to lard or butter for cooking purposes and it is less expensive.
Most of the olive oil imported into this country comes in large casks or hogsheads and is put into cans and bottles after it reaches the United States. There are also many gallons imported each year in bottles and cans. Some of the largest wholesale grocery houses and other importers have the oil bottled in France and Italy and Spain especially for their use and under the supervision of their agents. In a normal year Italy sends us 4,000,000 gallons, France nearly 1,000,000 gallons, and Spain about 350,000 gallons. California alone makes more than 200,000 gallons and is making more each year. The finer grades of California olive oil are noted for their flavor and purity.
Cottonseed oil. Less than a hundred years ago the cotton growers of the world found it difficult to dispose of the seed cleaned from the "lint" or cotton. Until recent years the seed of the cotton plant was practically sheer waste. But to-day the oil pressed from the seeds of the average American cotton crop is an important addition to the food resources of our country, being valued at about $100,000,000.
Thus many million dollars each year are snatched from the waste heap and turned into the pockets of the growers and handlers of our cotton crop. But the fact that the cotton plant, which has for centuries done so large a share of the work of furnishing the clothing for mankind, has added to its usefulness by joining the ranks of the food producers `is possibly still more important.
The contribution of the cotton plant to our food ' resources is not, however, confined to the wholesome oil taken from the seed and directly consumed by man. The pulp from which the oil has been pressed has become one of the staple foods for the fattening of live stock, especially in the South, and millions of tons, in the form of cottonseed cake and meal, are used for this purpose each year. Great quantities of this by-product are also used in the manufacture of fertilizers for the feeding of crops.
Making cottonseed oil. In expressing or extracting cottonseed oil, the seeds are thoroughly cleaned, then crushed in machines resembling those in sugar-cane mills. This pulp is then put into woolen press bags and subjected to strong pressure. After the oil has been extracted, that which is left is called cottonseed cake.
The oil from the presses is pumped into large tanks, from which it is either sold in the crude state or passed on to the refiner. In the refinery, caustic soda is added at a temperature of from 110° to 120° F., with the result that the undesirable fatty acids are neutralized and drop to the bottom of the mixture. The oil is then washed free of this sub-stance and allowed to clarify. It comes out of the clarifier a beautiful lemon yellow.
Cottonseed oil is used in the packing of sardines and other products; as a substitute for olive oil in cooking; and in combination with olive oil for salad dressings. It is also used as a lubricant for machinery.
The fatty acid portion, or cottonseed "stearin," is employed in the manufacture of compounded lard, the lower grades being manufactured into soap. The seed yields a maximum of about 35 per cent oil.
Cottonseed oil exports and imports. Cotton is grown mainly in the United States, Egypt, India, and South America. Cotton seed is exported from all these countries to Europe, where it is made into oil.
According to United States government figures, in a single year this country exported 47,457,000 gallons of cottonseed oil; in the same year the United Kingdom exported 6,099,000 gallons and Belgium exported 1,341,000 gallons. But in the same year the United Kingdom imported 7,587,000 gallons and Belgium imported 2,876,000 gallons.
This means that the United Kingdom and Belgium raise no cotton but simply act as refiners of cotton-seed oil.
The largest consumers of the oil are Germany, Italy, and France. In one year Germany imported 7,900,000 gallons, Italy 5,388,000 gallons, and France 3,697,000 gallons. Of these three countries, France was the only one to export any considerable amount of cottonseed oil, sending 172,000 gallons abroad.
Nut oils. A wide variety of nuts are important as the source of large quantities of oils. The oil pressed from the raw peanut ranks commercially with cottonseed and olive oils. It is used in making oleomargarine, and to take the place of butter and lard in cooking. It is also valuable in the packing of olives and sardines. Large quantities of oils from the almond, the coconut, and the walnut are used in cooking and confectionery, chiefly as flavoring. Other nut oils are those secured from beech nuts, Brazil nuts, ground nuts, and hazel nuts.
We used to import most of our peanut oil from France and Germany, where great quantities of African peanuts are pressed for oil each year. But in late years American peanut growers have learned the value of peanut oil and we are now producing large quantities of it. A bushel of peanuts weighing thirty pounds will yield about a gallon of oil. While the African peanut in the amount of oil it contains is richer than our southern nut, yet American peanut growers are finding the cultivation of peanuts for oil a profitable business. The production is now about 40,000,000 bushels a year but this does not supply the demand.
Corn oil. Corn oil, an increasingly important item in our food supply, is made from the germ of the Indian corn kernel. In the making of corn products, starch, sirup, sugar, and gluten, the germ, which contains a large proportion of oil, is separated from the remainder of the grain. These germs are dried, ground, and then pressed to secure the oil.
By refining and filtering, a valuable oil is produced. useful as shortening for bread and pastry, for frying and cooking, and as a salad oil. The unrefined oil is used in the manufacture of soap, lubricating oil, and a substance that can be used as a substitute for rubber.
In the United States we make about 75,000,000 .pounds of corn oil and 90,000,000 pounds of corn-oil cake a year. The corn-oil cake, which is made from the substance that remains after the oil has been pressed from the germ, is a valuable food for fattening live stock.
Bean oil. An important source of oil that has come into notice in recent years is the soy bean, a product originally grown in Eastern countries, especially in Japan, China, and Chosen. The plant is an annual, growing chiefly in bush form with a tendency to climb.. It bears pods containing from two to five beans. The beans vary in color, but are chiefly yellow, green, and black. The plant is raised successfully in the United States, in North Carolina, Tennessee, and other southern states, where it is grown with corn. Besides being of great value as forage, the plant resembles peas, beans, and alfalfa in its nitrogen-storing properties and hence is valuable as a soil improver.
Soy bean oil is imported from China, Japan, and India. Its value as a substitute for lard in cooking and as an ingredient in the manufacture of salad oil and oleomargarine is being recognized more and more. The plant is marvelously prolific and the oil, so valuable that agricultural and commercial circles in the United States are now devoting increasing attention to the cultivation of the plant. The oil cake that remains after the oil has been pressed from the bean has proved a valuable food for dairy cattle. The use of bean oil in the United States and Europe in the manufacture of oleomargarine and salad oil is steadily increasing. The oil is extracted in much the same way as olive oil. The beans are crushed, heated slightly, and then subjected to-steam pressure. Soy bean oil, in various degrees of refinement, can be put to the same uses that other vegetable oils are put. It may be used as a lubricant, as an illuminating oil, in the manufacture of soap, and in making a substitute for rubber.
In Eastern countries the beans themselves are an important food resource. They are eaten boiled with meat. They are made into a meal which is used in bread making. A sauce known as shoyu or soy sauce is made by boiling the beans with an equal quantity of barley, then allowing the mass to ferment, after which it is salted and strained. This product is an important ingredient of certain popular meat sauces.