New Uses for Farm Crops

by H. T. HERRICK

CONGRESS in 1938 authorized the establishment of four regional laboratories to work on new scientific, chemical, and technical uses for agricultural raw materials. Commodities in surplus and important to each area were assigned to the laboratories, which, named for the four points of the compass, are located in Peoria, Ill.; Wyndmoor, Pa., adjoining Philadelphia; New Orleans, La.; and Albany, Calif., near San Francisco. The buildings were completed and work was started in 1940 and early in 1941.

In the few years since, the results of research in the laboratories have made a deep impression on the life of the Nation. From them have come a process for the production of penicillin; a way to make sweetening materials from wheat flour; rutin; sweetpotato starch, and many other products and processes that are described elsewhere in this volume. Many other pieces of work are going on or have been finished. They are being fitted into the mosaic of the industrial utilization of agricultural raw materials and into the lives of all citizens.

Northern Regional Research Laboratory

The Northern Regional Research Laboratory in Peoria is assigned the task of finding new uses for corn, wheat, and the less important cereal crops; soybeans and other oilseed crops of the area, and agricultural residues. This last project is more national than regional, because it deals with agricultural residues of all kinds straws, stalks, corncobs, hulls, and such wherever found in the United States.

Just as cereal crops are the most important commodities in the laboratory, starch is the most important component of the cereal crops. Focused on it are many lines of research fibers, adhesives, industrial fermentations, and chemicals of industrial importance. There is a starch acetate fiber, for instance, that has certain properties all its own, although it resembles the cellulose acetate material that is prepared from cotton linters and other cellulosic raw materials. There is saccharic acid, which may find wide use as a food acid, and there is a family of products that stem from the action of micro-organisms on starch or the corn sugar manufactured from starch. Penicillin is the outstanding product of fermentation. Another part of the work with fermentation is making alcohol from the starch found in the cereal grains of the Midwest. The studies include work on a laboratory and a pilot-plant scale. A pilot plant is an experimental production unit equipped to work with industrial materials and processes on a scale somewhere between laboratory and full industrial size. Much information on the production of alcohol from wheat was made available to industrial users at a time when the properties of wheat as a raw material for alcohol were unfamiliar to many persons.

Two processes were developed for the production of starch from wheat and wheat flour. Conversion of the wheat starch commercially produced by these processes into glucose sirup and dextrose sugar provided millions of pounds of sweeteners. Some day the processes may provide an outlet for surplus wheat.

Besides starch, all cereals contain proteins of various types. When starch is manufactured from corn, these proteins are found in the so-called corn gluten, which is ordinarily used for cattle feed. This gluten is treated industrially with alcohol to extract an alcohol-soluble protein known as zein. Research in the Northern Laboratory has indicated the possibility of using zein in the production of a promising industrial fiber which, in both wet and dry strengths and in other properties, compares favorably with fibers prepared from other protein materials. Zein has also found wide industrial use in shellac, printing inks, and adhesives.

The growing of soybeans, a more recent crop than corn and wheat in our national economy, has increased rapidly during the past generation. Soybeans contain an oil that lies midway between the more commonly used food oils and the so-called paint oils. There are great possibilities in both directions. Much of the research at the Northern Laboratory on soybeans has been devoted to improving the properties of soybean oil to a point where it can meet the competition of other oils in their own particular fields. For example : Soybean oil in storage may develop unpleasant flavors that make it undesirable for use in cooking fats, salad oils, and other foods. Research workers at the laboratory have studied the problem several years and have made progress in correcting the difficulty. For paint, soybean oil has desirable and undesirable qualities. It is more or less immune to the yellowing that has been objectionable with interior linseed oil finishes, but it does not dry fast and hard enough to be used for the best type of surface coatings. Research has indicated that a new chemical treatment can cut the drying time of the oil without affecting its other properties. The new process has been made available to the industry.

Other materials produced from soybean oil are Norepol and Norelac. (Names of many products of the laboratory contain the first syllable of Northern and Regional, and another syllable that describes the product.) Norepol, a rubber substitute, filled a gap during the early days of the war before synthetic rubber was in large-scale production. Norelac, a thermoplastic resin, was in industrial pilot-plant production for more than 2 years before it came on the market as a full-fledged commercial product. Norelac is largely used as a heat-sealing and waterproof coating for paper and food packaging.

Tons and tons of cornstalks, corncobs, straw, hulls, and similar materials are wasted or poorly used on United States farms. To put them to good use is a national problem. They can be used unchanged or modified by chemical treatment. One use for some of them is to make a substance that replaces sand for cleaning machine parts, castings, and so on. It is expected that with the increase in the cost of wood, agricultural residues, like straw and stalks, will find a wider use in making paper. Much research has been devoted to this development.

The difficulties are largely economic. The question always is, Will it pay? With the working out of proper procedures that will collect the residues and deliver them to the factory at a reasonable price, there is no reason why these materials may not take their place in the manufacture of paper.

With a new process perfected in the Northern Laboratory, it is possible to produce from agricultural residues furfural, a colorless, oily liquid used in purifying butadiene and making plastics, that has great promise as the basis for a new chemical industry; glucose, from which alcohol can be made cheaply; and lignin, a material that is now used as fuel but has great possibilities for chemical development. All this is done in a continuous chemical process. Agricultural residues also are used in making Noreseal, a product that may replace cork in seals and tops for bottles, plastics, and building materials.