CANNING

Several recent technological developments in canning, our largest volume food-processing industry, are noteworthy. In the past decade, canners have made increasing use of an innovation called high temperature, short time (HTST) preservation. In aseptic canning, another new process, the product and can are sterilized independently. This not only maintains quality, but also reduces cost. Hydrostatic preservation has been used in Europe for some years but is a recent canning innovation in the United States. This continuous system saves steam, cooling water, and floor space.

Innovations, such as the use of aluminum and the zip-top, pop-open-top, and thin-tin cans, continually change the can market and keep it in a state of

transition.

FROZEN FOODS

The frozen-food industry, developed almost entirely since World War II, now produces an annual volume of over 10 billion pounds. Vegetables, poultry, concentrates, and prepared items have had the greatest recent growth.

Fluidized-bed freezing cuts down on freezing time for products such as green peas, beans, corn, and diced potatoes. It reduces investment, processing costs, and floor space requirements. Another important marketing innovation is the recent introduction of partly or completely prepared frozen items. Since these foods incorporate preparation, convenience, and "chef service," they improve the competitive position of the freezing industry. Boil-in-the-bag foods are an example. Processors add cream, white, butter, or other sauces before sealing the bag and freezing the food. This concept may be a major breakthrough in frozen food convenience.

Another innovation in the freezing industry is low-temperature freezing. This is truly "quick" freezing, with temperatures ranging downward to 320° F. below zero. The method allows freezing of such products as melons, mushrooms, avocados, and seafood that are difficult to handle under ordinary freezing conditions. At present, several companies are trying the process on a commercial basis, using nitrogen, freon, and other liquid gases.

DEHYDRATION

The primary advances in dehydration include new methods of heat injection and water removal, and improvements in packaging. Continuous belt tunnel driers have been replacing older atmospheric tunnel driers. Fluidized-bed drying of vegetables has become important. Drum drying has recently been adapted for drying sweetpotatoes, pumpkins, and applesauce.

Vacuum drying of whole milk powder may be a major innovation for the dairy industry. Currently, foam-mat drying, another USDA innovation, is being applied to citrus, tomato, and other juices. No products are yet on the commercial market.

Food preservation by freeze-drying had its early commercial beginnings in the late fifties but did not become economically practical until recently, as newer methods of applying heat and removing water lowered costs. Now, 50 or 60 products are on the market. Volume of freeze-dried foods in 1966 was more than 50 million pounds. In 1970, it may be 350 to 500 million pounds. Although an expensive method for preserving most foods, freeze-drying is applicable to specialty items and ingredients when a high-quality dried food is needed. Innovations, especially those lowering costs, will allow the new processing method to be used on more foods for more uses.

Explosive-puffing, long used in the preparing of grains for the breakfast cereal industry, is now an innovation in fruit, berry, and vegetable drying. Diced

carrots and beets, sliced apples, and blueberries are among the newer explosivepuffed dried foods, and driers now market several of them.

Reverse osmosis and osmosis combined with vacuum drying are new dehydration methods that offer future promise for fruits and vegetables.

OTHER PROCESSING METHODS

Irradiation has been discussed as a new processing method for years. Within the last 2 years, the U.S. Food and Drug Administration approved cured bacon, potatoes, and wheat for radiation processing, and the U.S. Army is now receiving bids for procurement of these items. Radiation may be used in highlevel treatments to sterilize (destroy all bacteria), or a milder or pasteurization treatment may be used to reduce the number of bacteria. Radiation is also used for sprout inhibition and to kill insects or larvae. Still another use is to extend shelf life of fresh, frozen, and canned foods. Fresh fish, for example, may have its shelf life extended by 12 to 24 days.

ADVANCES IN AGRICULTURAL RESEARCH AND TECHNOLOGY

ANIMAL DISEASES AND PARASITES

Animal diseases and parasite research has shown that bluetongue virus multiplies in the vector, Culicoides variipennis. This is the first time replication of an arbovirus affecting animals has been demonstrated in the insect vector and is an important fundamental step toward control and eradication of diseases caused by arboviruses.

Foot-and-mouth disease virus has been found to have an affinity for the bovine skin and may persist in the skin for as long as five days after cessation of viremia in experimentally infected steers. A previously undetected component has been found that is apparently associated with infections of foot-and-mouth disease, but is not part of the virus which causes this disease. It has been tentatively termed "virus infection-associated antigen" (VIA), and since it does not appear to be type-specific, may be responsible for many of the difficulties encountered in the diagnostic typing of this disease agent. A technique for detecting trace amounts of foot-and-mouth disease virus using calf kidney cell cultures has been developed.

Ultraviolet radiation and the organism, Moraxella bovis, have been found to work together to cause pinkeye (infectious keratitis) in bovines. The finding that ultraviolet radiation plays an etiological role makes possible the further study of the disease under controlled conditions any time of the year.

A series of experiments showed that the earthworm is a significant agent in the transmission and epizootiology of blackhead in turkeys and chickens. CURRENT TRENDS IN BASIC RESEARCH

Animal disease and parasite research will continue its efforts to develop new and improved methods and information directed toward more efficient disease prevention, control, treatment, and eradication. This will be accomplished by investigations that will attempt to characterize disease agents, and elucidate the interrelationship of the disease agent, the animal host, and the environment. Parasitological investigations will emphasize the biological control of parasites with an objective being to reduce dependence on pesticides.

AGRICULTURAL ENGINEERING

STRUCTURAL BIO-ENGINEERING

Emphasis has been maintained on bio-engineering particularly with respect to obtaining information useful in the design of livestock and poultry shelters. Work on interaction of climatic factors and production has continued, including that of the relationships of climatic factors and poultry diseases.

Additional basic data on heat and moisture dissipation avenues and rates have been developed for design of ventilation and/or air-conditioning systems for controlled environment shelters.

Increased emphasis has been placed on developing economical and sanitary means for managing the increasing concentrations of animal wastes accumulating in confinement type operations.

A design has been developed for an automatic, low-volume, livestock sprayer that provides good control of biting flies and reduced hazard from chemical residues.

Study has been initiated on pesticides reaching farmstead water supply systems and on developing means for keeping pesticides out of farmstead water supplies.

A Phyto-Engineering Laboratory has been established to develop design criteria for structures and related equipment to control plant environments for research and commercial production.

Research to improve the quality and reduce the cost of housing for seasonal and migratory agricultural workers is being emphasized.

DIMENSIONAL ANALYSIS AND TILLAGE TOOLS

Engineers have been successful in applying dimensional analysis to tillage tools. This technique permits the analysis of experiments on varying sizes of tillage tools conducted under different soil conditions. It also permits testing of improved tillage equipment and comparison of new equipment with older equipment even though experimental conditions may vary considerably from older tests. Dimensional analysis also permits testing of scale models of tillage tools. The advantage of this type of analysis of experimental work is a great reduction in the number of tests required to make a complete comparison between two types of equipment. Also, use of scale models to predict performance of large equipment results in considerable savings in developing new equipment.

HARVESTING-PROCESSING FIELD CROPS

Engineering progress is continuing in the harvesting, handling, and processing of cotton, peanuts, tobacco, grain, feed, and seed crops. During 1965 work was closed out on castor beans and long vegetable fibers and publications are being prepared. Significant reductions are being made in the cost of harvesting and handling such crops as peanuts and fruit. For most crops, mechanical harvesting, handling, drying, and cleaning machinery are in an advanced stage of development.

BEE MANAGEMENT IMPROVEMENTS

Several contributions have been made by engineers in improving existing equipment or developing new equipment to reduce labor in the management of bees and handling of honey. Automatic controls have been developed for honey extractors and can fillers. Improved designs of uncapping equipment, honey filters, and honey heating and cooling equipment have provided beekeepers with more efficient units for processing the honey crop at the apiary.

ANIMAL HUSBANDRY

Trends in livestock and poultry production continue toward larger and fewer farm units. Output per animal and per unit of labor input continues to rise. New research findings and their application encourage these trends.

BROILER, EGG PRODUCTION

Broiler production continued to increase. Benefits result from application of research, bringing about increased pounds of meat per pound of feed. While egg production per hen continues to increase there is evidence of a leveling off due to genetic and environmental limitations. New knowledge of amino acid, lipid and other requirements of poultry continue to increase the effectiveness of poultry rations.

DAIRY BREEDING

Milk production per cow continues to increase at an accelerated pace. This is a reflection of application of research on genetic improvement, artificial insemination and increased rates of concentrate feeding. The introduction of techniques to estimate breeding value of cows, along with improved methods for evaluating sires, offers breeders the opportunity to double the rate of genetic progress for milk production. More than 20 percent of dairy cows are participating in the record of performance program. These cows produce at a 50 percent greater rate than the non-recorded cows.

More than 45 percent of the dairy cows are bred by insemination. LIVESTOCK RESEARCH

Artificial insemination is rapidly increasing in beef cattle. Research has demonstrated the advantages of crossbreeding to increase reproduction and growth rate in commercial beef cattle. Better cattle and more efficient rations are increasing the numbers finished in feed-lots. Increasing numbers of steers from the dairy herd are being fed out for beef, thus increasing the meat supply. Increasing use of non-protein nitrogen provides a cheap source of protein in the rations of ruminants.

Numbers of sheep continue to decrease. Research is placing emphasis on increasing the lamb crop by more multiple births and more frequent lambing. Progress is being made in developing more suitable meat-type hogs carrying less fat. Methods have been developed to synchronize estrus in sows, thus making artificial insemination with superior performance tested boars possible. Research programs with all classes of farm animals continue to emphasize: increase in feed efficiency; increase in reproduction rate; improving genetic ability; reducing the effects of stress; reducing or eliminating hazards to and residues on animals and animal products; improving herd and flock management systems; and improving consumer acceptability of animal foods. CURRENT TRENDS IN BASIC RESEARCH

Basic research continues to receive increased emphasis. About 35 percent of the USDA animal husbandry research effort is in basic research. This includes quantitative and biochemical genetics; immunogenetics; basic endocrine and reproduction physiology; energy metabolism and nutritional chemistry.

OVERSEAS RESEARCH

Overseas research is conducted under some 30 grant projects on various basic and applied production problems. Coordinated studies on blood typing of dairy cattle are conducted with some 20 foreign laboratories.

CROPS

PEARL MILLET LEAFAGE

The relative effectiveness in light utilization of different layers of leafage in a field of pearl millet has been determined. At a density of three plants per square foot at moderate and high light intensities, the lower leaves lost more by respiration than they gained through photosynthesis and growth was reduced. The highest growth rate was found with one plant per square foota density that intercepted 88% of the incoming light and allowed enough to reach the lower leaves to assure a maximum net photosynthetic rate for the field. Lower densities wasted incoming light.

SOYBEAN CYST NEMATODE

Control of the soybean cyst nematode is being accomplished by growing the resistant variety "Pickett" in infected areas to which it is adapted. Research has shown that susceptible varieties can be grown if they are used in the rotation only one year in four or five.

ALFALFA WEEVIL

Using new techniques, large numbers of alfalfa plants are being evaluated for resistance to the alfalfa weevil in breeding programs. First, seedlings are exposed to feeding by adult weevils until only 1 or 2 percent survive. Next, leaf discs from these are tested individually to confirm resistance to adult feeding. Selected plants are then tested to determine larval weight and survival on them. A final test is for difference in oviposition on plants surviving the three previous tests.

HERBICIDE APPLICATION TECHNIQUES

Two new methods of herbicide application are expected to increase effectiveness of treatment and reduce hazards to crops. In one, spray is directed to weeds growing above the crop and is prevented from falling on the crop by a recovery device which collects and returns the excess to the spray tank. The method is especially useful on tall growing weeds such as cocklebur and sesbania. Soil residue problems are practically eliminated and possibility of damage to the crop being sprayed is minimized.

The second method involves a device which converts the spray into a relatively thick foam which can be directed to the soil surface to give improved coverage and low drift hazard.

CURRENT TRENDS IN BASIC RESEARCH

Crops research involves continuing work on methods of lowering costs of production. A large part of the effort is on pest control with increasing attention being given to the biochemical nature of resistance to diseases and insects, and to basic research on weed control. Other work will be on plant physiology in relation to efficient production. Crop quality, especially protein content and composition, will receive greater emphasis in several of the grain and pulse crops.

OVERSEAS RESEARCH

Approximately 135 crops research projects are conducted in 18 foreign countries under the Public Law 480 program. These projects cover almost as wide a range of activities as those in the domestic research program.

Two overseas projects are conducted for the Agency for International Development (AID). One involves improvement of pulse crops in some Near Eastern and Asian countries. The second is concerned with improvement of sorghum, millet, and maize in Africa. There is participation also in the crop program being initiated in Vietnam.