Requirements of Preteenage Girls for Specific 

 Nutrients 



In research focused on nutritional requirements 

 for preadolescent girls, two central human meta- 

 bolic studies and companion animal studies were 

 conducted. Major variables in the first study were 

 level of protein and calcium intake. Variables in 

 the second study were quality of protein and cal- 

 cium levels. Results revealed important interrela- 

 tionships among nutrients as influenced by the 

 dietary variables of low quality, vegetable protein 

 diets common to low income groups in the South, 

 and calcium level. Diets that contained little ani- 

 mal protein and whose major protein source came 

 from cereals and beans produced an imbalance of 

 essential amino acids, poor iron utilization, and 

 altered excretion of certain vitamins. When the 

 same diet also included a low intake of calcium, a 

 negative phosphorus and magnesium balance de- 

 veloped. The study also provided evidence that 

 the present National Research Council's recom- 

 mended daily allowance for protein for children 

 are minimal and do not contain a sufficient margin 

 of safety. 



Abernathy. R. P.. S. J. Ritchey. M. K. Korslund. J. C. Gor- 

 man and H. O. Price. 1970. Nitrogen balance studies with chil- 

 dren fed foods representing diets of low-income southern fam- 

 ilies. Am. J. Clin. Nutrition 23:408. 



Abernathy, R. P. and S. J. Ritchey. 1"J72. Protein require- 

 ments of preadolescent girls. .\m. J. Home Econ. 64:56(1972) 



Abernathy. R. P., S. J. Ritchey and J. C. Gorman. 1972. Lack 

 of response to amino acid supplements by preadolescent girls. 

 Am. J. Clin. Nutrition. 25:980. 



Abernathy, R. P.. S. J. Ritchey. M. K. Korslund, J. C. Gor- 

 man and N. O. Price. Nitrogen retention by children fed diets 

 typically consumed by low-income families. Fed. Proc. 27:679. 



Davis. E. Y. and Priscilla G. Day. 1972. Lipoprotein response 

 of preadolescent girls fed low protein diets supplemented. 

 Fed. Proc. 3!:70L 



Cabacungan. M. B., R. P. Abernathy, and S. J Ritchey. 1968. 

 Effect of Phenylketonuria and level of protein intake on ratio of 

 hydroxyproline to creatinine in urine of children. Va. J. Sci. 

 19:165. 



Gorman, J. C, R. P. Abernathy and F. Schofield. 1969. The 

 effect of levels of protein and calcium on fat absorption and 

 serum lipids in preadolescent girls. Fed. Proc. 28:561. 



Gorman, J. C. S. J. Ritchey. R. P. Abernathy, M. K. Kor- 

 slund. 1970. Influence of dietary protein and calcium on serum 

 lipids of preadolescent girls. J. Am. Diet Assoc. 57:513. 



McCoy. Harriet, H. Lewis, and S. P. Yang. 1968. Serum pro- 

 teins and tissue levels of vitamin A from rats fed two sources 

 of protein. 1967. Fed. Proc. 26:636. 



Packett. L. V., Jr.. G. M. Serski, Huei-Yveh Lu Chien. 1972. 

 Biochemical evaluation of nutritional status and protein quali- 

 ty. Summary, l.X International Congress of Nutrition. Mexico 

 City. Mexico. 



Packett. L. V. and C. E. Wells. 1973. Thiamine and riboflavin 

 excretion as influenced by amino acids and calcium supple- 

 mentation to low quality protein diets. Int. Kongress fur dia- 

 tetik. Hanover. Germany. 



Price, N. O., B. E. Bunce, and R. W. Engle. 1970. Copper 

 manganese and zinc balance in preadolescent girls. Am. J. 

 Clin. Nutrition. 23:258. 



Price. N. O. and B. E. Bunce. 1972. Effect of nitrogen and 

 calcium on balance of copper manganese and zinc in preado- 

 lescent girls. Nutrition Reports International. 5:75. 



Spence, Nikki, P., R. P. Abernathy and S. J. Ritchey. Sweat 

 nitrogen losses from preadolescent girls on low nitrogen in- 

 takes. Fed. Proc. .30: (1971). 



Southern Regional Technical Committee. 1968. Metabolic pat- 

 tern of preadolescent children. Description of the 1967 study. 

 Southern Coop. Series Bulletin No. 129. Blacksburg, Va. 



Southern Regional Technical Committee. 1971. Metabolic pat- 

 terns of preadolescent children. Description of 1970 study. 

 Southern Coop. Series Bulletin No. 170. Blacksburg, Va., 

 1971. 



Chemistry of Fructose 



In studies of the basic chemistry of fructose, it 

 has been determined that a solution of fructose 

 contains three isomers. Unlike glucose, the dis- 

 tribution of the three isomers varies greatly with 

 concentration and temperature. This variation 

 complicates the use of fructose in food applica- 

 tions. 



Basic studies have revealed the three isomers 

 present in solution are the usual 6-membered ring 

 form as found for crystalline fructose, and the two 

 possible 5-membered ring forms. Study of the 

 properties has shown that with increasing temper- 

 ature, the concentration of the 5-membered ring 

 forms increases and alters food properties such as 

 water activity of the sugar and its sweetness and 

 browning activity. By use of a gas chromato- 

 graphic technique and computer analysis of the 

 data, optical rotatory properties of all three fruc- 

 tose isomers have been described. Basic data such 

 as these make it possible to understand the chemi- 

 cal behavior of fructose when added to food sys- 

 tems. 



High fructose corn syrup (HFCS) promises in- 

 dependence from foreign sources of sugar. Basic 

 data on the properties of fructose will allow food 

 manufacturers to control sweetness, nutritive val- 

 ue, flavor, and energy values of HFCS-sweetened 

 products over a broad spectrum, giving consum- 

 ers greater discretion in choosing their food and 

 beverage products. 



Lindley. M. G., Shallenberger, R. S. and R. L. Whistler. 1976. 

 Comparison of the sweetness of glucose and fructose with 

 their ring-thio analogs. J. Food Sci. 41:575-577. 



16 



AGRICULTURE 



