C&EN A N N U A L
REVIEW—1951
A trend toward food supply
higher nutritive quality
in the
has m a r k e d the year's progress
general in
Foods a n d Nutrition C. G . K I N G , Scientific
Director
and Professor of Chemistry,
J. w o features of m o d e r n living are un mistakable—the population as a whole does less m a n u a l labor, and, having dis covered h o w to p r e v e n t or cure most of the acute infectious diseases, survives into a higher age bracket. Both of these trends point toward a n e e d for higher nutritive quality in t h e general food supply. Among nutrition investigators and the medical profession t h e r e is agreement that the body's n e e d for proteins, many of the vitamins, a n d most of the mineral ele ments does not increase proportionately when the w o r k o u t p u t is raised. Hence, an office w o r k e r expending 2500 calories per day, c o m p a r e d w i t h an individual ex pending 5 0 0 0 calories per day, requires a food intake of higher nutritive quality to accomplish a c o m p a r a b l e level of health— especially t o have a n e q u a l chance of warding off t h e risks of degenerative dis eases such as h a r d e n i n g of the arteries, obesity, h i g h blood pressure, tooth decay, glandular imbalances, and diabetes, in creasingly associated with overeating and accelerated aging. Vitamin M e a s u r e m e n t and Functions T h e n e w vitamin, lyxoflavin, was re ported in 1951 as a n essential nutritive factor for microorganisms a n d albino rats. T h e new vitamin a p p a r e n d y differs from vitamin Ba (riboflavin) only in the con figuration of a single carbon atom. Thus far no e v i d e n c e h a s been published in regard to t h e possible role of t h e vitamin in human nutrition. Identification of t h e "citrovorum factor" represented another a d v a n c e d u r i n g the year. This n e w vitamin form, studied through several years as a n essential nu trient for microorganisms, was shown to be active in a role similar to t h e other forms of folic acid in b o t h h u m a n and animal nutrition—a protective agent against macrocytic anemia. 18
o f the Nutrition
Columbia
University,
Foundation New York, Ν. Y.
Distinct progress was also m a d e during meat, eggs, fish and related p r o d u c t s ) , t h e year in identifying a n d measuring t h e ( 2 ) green leafy foods, ( 3 ) citrus fruits, multiple forms of pantothenic acid ( c o bananas, t o m a t o e s and berries, a n d ( 4 ) enzyme A ) . T h e steadily expanding n u m requisite s o u r c e s of calories, represent b e r of instances in which a vitamin occurs the types that a r e increasingly important. in natural products, linked with many dif T h e y can readily-- furnish all the nutrients ferent a n d interchangeable groups, r e p r e in proportions t-hat a r e well a d a p t e d to sents o n e of the most active aspects o f the protection o F health. biochemical research. Among microorgan D u r i n g t h e pa_st year, interrelationships isms, t h e differences in assay response t o were extended notably, relating c, /iifeeding the various forms o f a single to vitamin Bi2, folic acid, a n d asc Drbic vitamin such as folic acid or p a n t o t h e n i c acid, and these in turn to t h e amin· Ρ ids acid m a y be almost absolute, but fortu methionine, cystine, phenylalanine. d nately the various conjugates generally tyrosine. Additional p r o g r e s s Ά a simi* h a v e about equal value for the higher a n i nature has extended t h e r a n ^ e of q u a n t i mals, including m a n . W e r e it n o t for t h i s tative and functional interrelationships b e capacity of the higher animals to utilize tween niacin, pyridoxin, t r y p t o p h a n , gly efficiently multiple forms of m a n y vitamins cine, and other amino acids. In c o m m o n a n d reconstruct t h e m into their own essen feeding s i t u a t i o n s there are m a n y a p tial enzymes, the problems of maintaining proximate intercliaiigeabilities, as b e t w e e n a satisfactory food supply would be i m methionine and -choline a n d b e t w e e n folic mensely more difficult. acid and v i t a m i n B12, b u t t h e substitutions Chemists naturally prefer t o use p r e are not absolutes. cise names for individual substances, b u t Earlier r e p o r t s t h a t cobalt-deficient it is a great advantage to h a v e a single lambs w o u l d n o t respond t o injections of name to cover the multiple forms of Q. vitamin B u - s u r p r i s i n g at t h e time—were particular nutrient. Hence, the long-estab found to h a v e soi explanation in t h e fact lished practice of referring to a group o f t h a t the supplied, dosage of vitamin Bu» h a d nutritionally interchangeable compounds n o t been a d e q u a t e t o m e e t the animal's b y a single name is likely to continue. n e e d . W h e n t:he injected quantity of vitamin B12 was raised to 150 micrograms, Interrelationships a n d B a l a n c e s t h e r e was a distinct c u r a t i v e effect upon As t h e multiple functions of nutrients t h e cobalt-induoed anemia. Extensive foo-ds assays led to t h e con b e c o m e more clearly identified, it is e v i d e n t t h a t the interrelationships between i n clusion t h a t cereals, fruits, and vegetables dividual vitamins, amino acids, sugars, a r c characteristically low in vitamin Bia fatty acids, and even the mineral elements, ( 1 to 3 m g / g j , in contrast to t h e animal that are generally good a r e so intricate and so significant in t e r m s protein foods of requirements, that defining dietary r e sources ( 3 6 to 4380 m g / g ) . quirements becomes exceedingly difficult. Yet approximate figures are valuable i n M i n e r a l B a l a n c e s many practical situations. T h e R e c o m Practical a n d theoretical aspects of t h e m e n d e d Dietary Allowances d o not l o s e interplay b e t w e e n c o m m o n mineral ele their broad significance. I n appraising m e n t s h a v e be-en developed further, in h u m a n food supplies, for example, ( L ) c l u d i n g several reports on sodium, potas high quality animal protein foods (mille, sium, a n d magnesium. W o r k in this field CHEMICAL
A N D
ENGINEERING
NEWS
DEVELOPMENTS I N THE CHEMICAL A N D PROCESS INDUSTRIES has had increased interest in relation to the functions of ACTH and cortisone and in relation to nutritional therapy in the treatment of burns, trauma, radiation injuries, and severe hemorrhage. Further evidence was developed also, concerning the close interrelationship between molybdenum, copper, and phosphorus in animal arsd plant nutrition—extending the known interdependence between copper, iron, and cobalt. Nutrition and Development Of the Central Nervous System Folic acid had been identified curlier 9« a protective agent against hydrocephalus in experimental animals (rats). Two interesting extensions in this area of research developed during the year. Mar-
ible or irreversible injury to the central nervous system. Cholesterol Extensive research programs are under way both with experimental arrimais and with human patients in relating cholesterol formation and deposition to the degenerative diseases. Abnormal deposits of cholesterol in the blood vessel walls and in many other body tissues represent a frequent feature of such diseases as poorly controlled diabetes, hardening of the arteries, and high blood pressure. There is a tendency for such deposits to accompany the processes of aging, b u t they are not essential characteristics of old age. Many types of nutritional deficiency exaggerate the tendency to deposit choles-
Tooth Decay A greatly increased amount of evidence indicates that fluoridation of public water supplies, under good technical control, represents a major contribution to the prevention of tooth decay. It appears that a large fraction of the total American population will benefit from this new development. Thus far there have been no indications of injury to health as a result of fluoridation. In a few communities there have been objections to the fluoridation program, based primarily upon either misrepresentation or misunderstanding of the most elemental principles in physiology as related to human health. An interesting report from Oregon emphasized a factor that has been given only minor consideration in recent years, namely a lessened incidence of tooth decay in areas characterized by a greater incidence of sunshine. Presumably the effect resulted from a more generous supply of vitamin D. An important feature of nearly all of the recent findings is the evidence that good nutrition during the very early stages of tooth development is particularly important—including both prenatal and postnatal periods. Antibiotics Continued reports furnish evidence of practical advantages from the use of antibiotics as constituents of feedstuffs for hogs, chickens, and turkeys. Because of the many variables, including the composition ot the ration and îhe bacterial flora in the intestinal tract, it is not surprising that there is great variation in the responses gained in different areas. On the whole the picture is a substantial one when interpreted in terms of practical advantages from a more favorable intestinal flora, thus giving rise to greater availability of essential nutrients (by greater synthesis or less destruction) and less injury to the organism resulting from toxic products of bacterial action.
The "consumer" is the final judge of a ration. Here, soldiers in the field take time out for warm food from their 5-in-l ration, a product of research ginal deficiencies were shown to have a deleterious effect upon the maze-learning capacity of experimental animals. In addition, structural defects in the central nervous system were clearly evident. A closely related study resulted in finding that a synthetic analogue of folic acid (acting as an antivitamin) could exert striking effects upon the embryonic development of albino rats. Such "induced deficiencies" during gestation resulted in gross malformations in the offspring. The gross anatomical defects were very similar to those observed earlier as a result of riboflavin or vitamin A deficiency during gestation. Although the results with experimental animals are striking, there is little evidence at hand to indicate their possible bearing upon human nutrition. It is well known, however, that oxygen deficits for short periods in infants either after or before birth can result in reversV O L U M E
3 0,
NO.
1
»
»
terol, but perhaps the most striking of these is the relationship to choline. The general relationship includes other vitamins in the B-complex, however, and some of the amino acids. The influence of cholesterol intake, as against abnormal synthesis and faulty utilization, represents an area in which practical interpretations are difficult to make at the present time. Labile acetate groups, readily derived from excess fatty acids and sugars, represent a major common unit in cholesterol synthesis that can overshadow the effect of cholesterol ingested as food. The long years of patient research in studies of the intermediate fragments in burning common foodstuffs, and the related studies of the catalytic role of many of the vitamins, can be seen currently as a contribution to perhaps the most important problem in which nutrition is related to public health.
J A N U A R Y
7,
1952
Enrichment Gains One of the most striking demonstrations • of gains in public health as a result of cereal enrichment is evident from surveys conducted in The Philippines. Addition of thiamine, niacin, and iron to white rice in the Bataan area has been followed by distinct gains in health. The findings in^» eluded a widespread rise in hemoglobin values ( indicative of the response to increased intakes of iron ), higher blood and urinary concentrations of thiamine, and a lessened incidence of beriberi. During the period there was no evidence of other major changes in the dietary pattern nor in the incidence of other nutritional deficiencies beyond those corrected in the enrichment program. Widespread vitamin C deficiency, for example, remained practically unchanged and low blood carotene values indicated a continued low intake of green leafy and yellow vegetables. The food faddists have staged a jamboree during the year, with apparent great 19
C&EN A N N U A L
REVIEW—1951
financial gains for themselves. On the other hand, reliable educational measures have also been outstandingly successful, and there has been an u n p r e c e d e n t e d demand for good cook books—a valuable gain, surely! T h e public does not have the benefit of protection in press and radio such as provided b y industry a n d by regulatory agencies in t h e field of labeling and advertising. O n e of t h e substantial contributions in the public interest has come irom t h e Food a n d D r u g Administration in the following quotation from Commissioner C. \V. Crawford: "A small army of food faddists is abroad in t h e land p e d d l i n g nutritional nostrums. W e in America have the most a b u n d a n t a n d nutritious food supply and are enjoying t h e best health of any nation in history. But the food faddists are spreading t h e false doctrine that our staple foods are debased and deficient . . . then comes the gimmick—we can't get well and stay well unless we supplement our diets with some outlandish food or start dosing ourselves with a particular concoction of minerals, vitamins or what have you. A vigorous campaign of truth about nutrition a n d diet, as well as law enforcement, is n e e d e d . "
H e a t Effects InteiiM\ e r o e a r c h to lessen t h e changes in food products induced b> excessive heating, has contributed to relatively n e w developments, especially in demonstrating the possibility of continuous flow sterilization and sealing in sterile containers, so that a short-time-high-temperature sterilization can replace the long-continued heating in enclosed containers. A second development in the same direction is the increased prospect of accomplishing more efficient stirring ( e n d - o v e r - e n d ) of t h e contents of canned products during both sterilization and cooling, with resultant superior retention of nutritive quality, flavor, color, a n d other qualities essential to good acceptance. Sterilization of food commodities b y special forms of radiation has been studied actively with some progress b u t as yet little practical application. G a m m a radiation from cobalt 60 has offered considerable promise, especially because of t h e high penetration characteristics and t h e possible availability of radioactive b y products irom atomic piles. T h e work is still in a very exploratory stage, but with the combined interest of t h e Atomic Energy Commission, t h e food industry,
Price rises in natural synthetic
capacity
rubber
produced
«nd university research laboratories, it is evident that information of a basic and technologic nature will accumulate rapidly in t h e immediate future. Dehydration Defense measures have included a greatly accelerated research program dealing with the dehydration of vegetables, fruits, meat, milk, a n d eggs. Frozen Juices T h e great success of frozen concentrated orange juice has b e e n followed by vigorous research on other comparable products. Lemon juice a n d lemonade have enjoyed extensive acceptance quickly. Interest continued also in developing frozen concentrated grape juice a n d apple juice. Frozen milk h a s also h a d continued interest. Pectin Growing recognition of t h e importance of different types of intestinal flora has stimulated increased interest in t h e value of pectin a n d related products in the food supply.
and reactivation
of
a turbulent
in
year
Rubber J O H N T A T U M C O X , JR. f Consulting Chemical Engineer, Washington, D. C
R UBBER, one of man's most useful hydrocarbons, h a d a t u r b u l e n t year during 1951 'inside and outside the continental lines of the I nited States. Its price rose a n d d e clined u n d e r a series of impacts revolving a r o u n d t h e desire of the Government to assemble a n d maintain a large stockpile of natural r u b b e r for defense purposes. T h e mechanism of o b t a i n i n g stockpile objectives w a s through government-enforced product specifications and allocations of existing available supplies of both natural a n d synthetic r u b b e r , with the preponderance of t h e b u r d e n of U. S. consumption b e i n g carried by t h e synthetic r u b b e r industry, w h i c h is operated b y the Government. N a t u r a l ruibber p r o d u c t i o n for t h e year w a s approximately 1,850.000 long tons, 20
which included approximately 72.000 long t o n s of natural rubber latex. United States synthetic rubber production for the year \v.i> 848.000 long tons tor all types of rubbers, a n d broken down this gives 699.000 long tons of C.R-S: 7-3.000 long tons of butyl; 16,000 long tons X-types; and 60,000 long tons of neoprene. T h e U. S. consumption figure for all types was approximately 1,280,000 long tons. Reactivation Gets "Well D o n e " In reactivating the idle capacity of synthetic rubber, the Government has done an exceedingly fine a n d p r o m p t job. It was forced to raise GR-S prices from 18.5 cents t o 24.5 cents, a n d finally to 26 cents per p o u n d to cover t h e costs of reactivation, a n d to cover the use of high-priced C H E M I C A L
alcohol-based b u t a d i e n e . Butyl prices w e r e raised from 18.5 cents to 20.75 cents per pound. At die year's e n d the program was operating at an approximate rate or 800,000-ton capacity. T h i s capacity can b e raised almost immediately to 860,000 tons by t h e addition of certain easily obtained a n d quickly installed heat exchangers in the copolymer plants. T h e r e is synthetic r u b b e r production outside t h e United States of well established b u t unknown dimension. Exact figures of tlie reactivated G e r m a n production are not accurately known. W h a t "Professor Joe" a n d his cohorts are doing b e h i n d his curtain is a m a t t e r of mystery, w h i c h is p a r for t h e course on all matters t h a t Professor Joe deals with. However, it can safely be said t h a t a n y synthetic AND
ENGINEERING
NEWS
