144 PHILIPPINE RESINS, GUMS, AND OILS 



of oil from the castor-oil seeds and states that seeds from two 

 varieties grown wild in Australia contained 47 to 49 per cent 

 of oil. This yield is somewhat less than that obtained from 

 Calcutta and Java seeds, which give about 53 per cent of oil. 



The process of refining castor oil consists largely in removing 

 albumen by steaming the oil. The albumen and part of the 

 enzyme which has passed into the oil are thus coagulated and 

 removed by filtering. Castor oil keeps very well when refined 

 properly and does not easily become rancid. The percentage of 

 free fatty acids does not increase considerably on standing. Ac- 

 cording to Lewkowitsch * a sample exposed to the athmosphere 

 for four years contained only 1 per cent of free fatty acids. 



Castor oil has the following constants (Lewkowitsch) : 



Specific gravity (15.5°), 0.9591. 



Solidifying point -10° to -12°. 



Saponification value (Mgrms KOH) 176.7 to 186.6. 



Iodine value 81.4 to 90.6. 



Reichert-Meissl value (C.C.1/10 norm. KOH) 1.1. 



Acetyl value 149.9 to 150.5. 



Maumene test 46° to 47°. 



Refractive index (15°) 1.4795 to 1.4803. 



Oleo-refractometer (22°) 37 to 46. 



Butyro-refractometer (25°) 78°. 



Viscosity (Redwood's viscosimeter) 1160 to 1190. 



As shown by the figures above, the acetyl value is unusualb 

 high. Mitchell f states that castor oil has an acetyl value of 

 about 150 and emphasizes the fact that other oils and fats have 

 acetyl values ranging from about 2 (coconut oil) to 15 (cotton- 

 seed oil) and 19 (croton oil). 



According to Richmond and Rosario J castor oil could be man- 

 ufactured in a coconut-oil mill and, if the plant were cultivated 

 on a sufficient scale, there would be a possibility of the com- 

 mercial production of this oil for lubricating and illuminating 

 purposes. It could probably be sold as cheaply as coconut oil, 

 which is now used extensively in food products. 



Ricinus communis is a coarse, erect, somewhat woody bush 

 about 1 to 4 meters high. The leaves are smooth, alternate, 20 

 to 60 centimeters in diameter and palmately divided, with pointed 

 lobes. The leaves and stems are green or purplish. The fruit 



* Lewkowitsch, J., Oils, fats, and waxes, (1915). 



t Mitchell, C. A., Edible oils and fats, (1918). 



% Richmond, G. F., and Rosario, M. V. del, Commercial utilization of 

 some Philippine oil-bearing seeds: preliminary paper. Philippine Journal 

 of Science, Section A, Volume 2 (1907), page 448. 



