[136-138 



PART V 

 ANALYSIS OF FEEDING MATERIALS 



THE ANALYSIS OF OIL CAKES 



136. The examination of an oil cake may be divided into 

 two distinct parts : the quantitative and the qualitative. These 

 will be treated separately, as the first refers entirely to its feed- 

 ing qualities and the second to the purity and wholesomeness 

 of the seeds which it contains. 



Quantitative Analysis 



The substances usually estimated in a cake are moisture, 

 oil) albuminoids, woody fibre, ash, and sand. To these may 

 be added the carbohydrates, which are as a rule determined 

 by difference. 



137. Moisture. — Two grams of the ground sample of 

 cake are weighed out in a porcelain capsule, and heated in 

 a steam oven until of constant weight. Five hours is generally 

 sufficient time for this. 



138. Ash. — The portion used for the estimation of 

 moisture is removed to a weighed platinum dish — sweeping in 

 the last traces with a camel's-hair brush — and ignited, until the 

 weight is again constant. It must be remembered in perform- 

 ing this operation that some seeds, of which these cakes often 

 contain large quantities, have a high percentage of alkalis, and 



