448 SCIENCE PROGRESS 



explosives, waterproof goods, rubber substitutes, and printing 

 inks.^ 



Utilisation of Soya-Bean Cake and Meal 



For many centuries the sugar plantations of South China 

 have been treated with soya- bean meal ; its fertilising value 

 depends mainly on its store of nitrogen, but it contains also some 

 available phosphorus and potassium. The meal is employed in 

 Japan as a fertiliser for yams, rice-fields, and mulberry-trees. 



The cake and meal are in great demand for feeding stock 

 throughout the agricultural world. Analyses of both products 

 show a high food value ; feeding experiments with animals 

 prove that cattle, sheep, and pigs show very satisfactory growth 

 when soya-bean derivatives form a reasonable part of the daily 

 food ; injurious results, however, are obtained when the ration is 

 not well balanced. The meal and cake are as efficient as other 

 rich foods and are less expensive. 



Food Value of the Bean 



The high food value of the soya-bean is due to its oil and 

 protein content ; the oil when refined for edibl-e purposes is 

 well digested by the human body, and is useful for cooking 

 purposes. 



The protein content of the bean has formed the subject of 

 much investigation, especially in Japan and America. The 

 chief protein constituent, glycinin, contains both lysine and 

 tryptophane, which are recognised by students of nutrition as 

 essential for " growth " and " maintenance " respectively.* 

 Experiments on rationed animals have shown conclusively that 

 glycinin is superior for growing animals to gliadin, hordien, and 

 zein. Soya- beans compare very favourably with garden peas 

 and kidney-beans with regard to protein value and utilisation, 

 for the protein of peas and kidney-beans is of low biologic value 

 and badly digested.' Damets and Nichols^ hold that their ex- 

 periments indicate that soya-bean protein is as valuable as 

 the casein of milk. 



The exceptional position held by the soya-bean is sum- 

 marised by Osborne and Mendel as follows ^ : 



" So far as we are aware, the soya-bean is the only seed 

 hitherto investigated, with the possible exception of millet, 

 which contains both the water-soluble and in a limited quantity 



1 Table in Morse, U.S. Depi. Agr. Farm. Bull., 973, 1918. 



2 Osborne and Clapp, Amer. Journ. Physiol., 19, p. 468, 1907. 



3 Holmes. U.S. Dept. Agr. Bull., jij, 1918. 



* Journ. Biol. Chem., 32, p. 91, 1917. 



* Osborne and Mendel, Journ. Biol. Chem., 32, p. 369, 1917. 



