4 The Philippine Journal of Science i»is 



color and of high activity, could hardly be made by the native 

 process outlined above. An attempt is, therefore, made to meet 

 the requirements of London and Hamburg dealers by blending 

 No. 1 with No. 2. This gives No. 2 mixed (Plate II). The 

 two components may readily be recognized in such a mixture, as 

 the individual lumps are large enough to render separation by 

 hand picking a simple matter. The eflect of this blending is to 

 lighten the color considerably, but at the same time very greatly 

 to decrease the activity of the gum. It will be shown later that 

 the light-brown fragments of highly adulterated gum are prac- 

 tically inert, and as this grade frequently comprises from 30 to 

 50 per cent of an entire shipment it may be seen how seriously 

 the product is injured. Many dealers in Colombo informed me 

 that they were adverse to blending the two grades of papain 

 in this manner, but that dark-colored No. 1 was unsalable and 

 pure light-brown gum could not be made. The latter statement 

 does not correctly represent the situation, as Mexican papain is 

 lighter in color and the West Indian product resemble? dried 

 bread crumbs. 



Further difficulties have arisen during the past year. Many 

 shipments of Colombo No. 2 mixed have been refused admitt-ance 

 by the United States customs, because adulterated with starch 

 although invoiced as papain. Thus the sale of Ceylon papaya 

 gum has decreased considerably, but various brokers who have 

 dealt in this product for many years informed me that they 

 could readily sell at least a ton per month of high-grade papain 

 provided it were free from adulteration and light colored. 

 Quotations from various drug houses in the United States 

 indicate that properly prepared gum would find a ready market 

 at prices ranging from 11 to 13 pesos per kilogram (2.50 to 

 3 dollars per pound). 



This investigation was undertaken for the purpos.e of com- 

 paring papaya gums made in a variety of ways and, especially, 

 to ascertain whether it was possible to conserve the entire effi- 

 ciency of fresh latex by employing proper methods for drying. 

 Various means for detei-mining the digestive value of papain 

 have been suggested from time to time, and many firms handling 

 the gum employ arbitrary standards based upon what they con- 

 sider a satisfactory preparation. Graber- uses finely ground 

 steak in dilute hydrochloric acid solution, Rippetoe ' prefers 



'Journ. Ind. & Eng. Chem. (19in, 3. 919. 

 "Ibid. (1912), 4, 517. 



