& 



50 



ing his results at the disposal of the Board of Agriculture, it is now 

 possible to form some definite opinion as to the possibilities of cassava 

 starch as an industry for Jamaica 



The experiment at Longville has been of a tentative character and 

 the actual possibilities of the industry when established on a reasonable 

 commercial scale and with the best machinery Hnd m magement are 

 far in excess of those directly indicated by Mr. Middleton's preliminary 

 results. 



Agricultural Y^eld. 



The returns of tubers per acre at Longville as recorded by Mr W. 

 J. Thompson, varied considerably. Where the cassava had beea 

 planted between bananas or under shade the yield was not satisfactory. 

 Eight tons of tubers per acre were obtained on one piece of land, and 

 there is every reason to believe that by thorough tillage and the propa- 

 gation of the best varieties of c ssava a return of 10 tons per acre can 

 be reasonably expected. Mr. Joseph Shore finds that this is a fair 

 return from lands in cassava on the northside. 



The cost of production at Longville was 10/6d pr r ton with an 8 ton 

 crop allowing £1 per acre for rent. I estimite that the cost of produc- 

 tion can be reduced to 8/- per ton by reasonable economies and improve- 

 ments in the cultivation. 



The Florida factories pay 18/- per ton for the tubers in the field, the 

 cost of digging and delivery to the factory being about 6/- a ton in 

 addition. 



Cost of Manufacture. 



At Longville 6 tons of cassava tubers pulped in a small St. Vincent 

 rotary grater yielded one ton of air-dried starch hj the West Indian 

 process. The cas-ava contained ab ut 29 per cent, of starch. The 

 actual cost of production of the starch including the growing of the 

 cassava, amounted to £8 per ton. 



By-Products. 



The bitty or residual pulp, when dried to a content of L5 per cent, 

 of moisture amounted to a return of 1^ tons of dry material to each 

 ton of starch The composition of this product closely corresponded to 

 that of the meal from the whole tubers sun-dried. Cassava bitty is 

 therefore a valuable food-stuff for cattle or pigs. If we deiuct 30/- 

 per ton fur the cost of expressing the excess of moisture, drying and 

 ! aggii g the bitty, its net value cannot be less than 30/- per ton to the 

 facte irv, on a low selling price of £3 per ton. A deduction of £2 per 

 ton on the cost of the cassava starch is therefore apparent. 



The cost of production of a ton of cassava starch with a process that 

 only recovers 60 per cent of the total starch in the tubers, is therefore 

 only 6 per ton. 



'^"ommercial I'rospects. 



The starch prepared by Mr. Middleton at Lon-iville was of variable 

 quality at the outset until a satisfactory method of working had been 

 arrived at. 



By careful neutralisation of tt e crude starch with soda, using litmus 

 papers as an indicator, it was found possible entirely to neutralise the 

 organic acids of fermentation that ai e inseparable from any process of 



