xii, a,* Brill, Parker, and Yates: Copra and Coconut Oil 



79 



However, it did appear possible that there might be a mechan- 

 ical carrying over of the oil with the escaping moisture, espe- 

 cially if the drying temperature were high and the driving off 

 of moisture rapid. Experiments were made by examination 

 of the gases from a mechanical dryer. The type of machine 

 used was similar to the ordinary oven dryer, but provided with an 

 arrangement for the circulation of hot air. The experiment 

 was carried out in the following manner : 



A weighed amount of coconut meat was distributed over the 

 trays and dried at various temperatures. The volume of air 

 passing through was calculated, and the temperatures at the 

 entrance and exhaust were noted. An aliquot part of the air 

 was withdrawn from the oven by means of a vacuum pump at 

 the rate of 1,200 liters per hour, measured by means of a gas 

 meter. " The air in passing to the pump and gas meter was con- 

 ducted through two series of four bottles, each containing chloro- 

 form immersed in a freezing solution in order to free the air of 

 oil. Four separate determinations were made, using drying 

 temperatures varying from 70° to 100° C, and in no case was 

 n qualitative test for oil obtained. 



Tablb XVIII. — Data on oil loss in mechanical dryer. 



Tem- 

 per- 

 ature. 



Freih 

 meat. 



Weight 

 loss. 



°C. 



Kilo*. 



P. cent. 



70 



100 



40.0 



80 



104 



42.0 



90 



102 



41.0 



100 



86 



44.0 



Determinatio* 1 ...'. 



Determination I . 



Determination J 



Determination 4 I 



Per cent. 

 0.0 

 0.0 

 0.0 

 0.0 



The results recorded in Table XVIII are opposite to the belief 

 of the Ceylon planters, as reported by Pratt : 1S 



The amount of copra from a given quantity of fresh nuts depends to a 

 considerable extent upon the rate of artificial drying. Ordinarily, from 170 

 to 200 nuts give about 50 kilograms (110 pounds) of copra. The two 

 extremes are encountered in comparing the output of sundried copra with 

 that of desiccated coconut products. * * * The decrease in time re- 

 quired for expelling the water is, therefore, coincident with increased Joss 

 of oil, and all methods of preparing copra must represent an economical 

 balance between these factors. It is unquestionably possible to make copra 

 in much less time than is required by either the sundrying or grill-drying 

 processes, but experiments made by planters in Ceylon have not impressed 

 them with the advisability of adopting such changes. One of the most 

 progressive coconut planters in the island constructed a drying house with 

 brick heating flues and produced paper-white copra in less than twenty-four 



Pratt, D. S., This Journal, Sec. A (1914), 9, 181. 



