352 



PROCEEDINGS OF SECTION B. 



passed over. The ammonia in the distillate is estimated by Nessler's 



solution, and the amount found multiplied by 5*2 gives the amount of 



albuminoids present. 



Diastase. 



The diastasic power was determined by the method recommended 



by the Malt Analysis Committee to the Council of the Institute of 



Brewing, December, 1905. A 5 per cent, solution of the extract is 



taken, from 2ccs. to 7ccs. of this (the amount depending upon the 



diastasic power) is added to lOOccs. of 2 per cent, solution of soluble 



starch in a 200ccs. flask. This is allowed to act for one hour at 20° C. ; 



N 

 lOccs. of-^^ — NaOH are then added to stop further action, the liquid 



cooled to 15° C, and made up to the mark. This solution is then 

 titrated against 5ccs. of Fehling's solution, using the starch iodide 

 indicator. After allowing for the reducing power of the extract added, 

 the number of ccs. of liquid required for the reduction of 5ccs. of Feh- 

 ling's can be calculated — the L° = -^ L° = diastasic activity ; 



X Y 



X equals the number of ccs. of malt extract per lOOccs. of diluted starch 

 conversion liquid ; and Y equals the number of ccs. of the same liquid 

 required to reduce 5ccs. of Fehling's solution. 



SVECTFIC RoTATioi^r [a] 



was determined in a lOOnim. tube by means of a Schmidt- Haensch 

 half-shadow polarimeter; the 10 per cent, solution being used after 

 decolorising by means of animal charcoal. 



From these results it is obvious that the method of determining 

 dextrin from the rotatory power after deducting that due to maltose 

 and dextrin does not give correct results. The oxidation method 

 gives results which, though they may not be quite correct, owing to 

 the presence of a large percentage of maltose, certainly give results 

 nearer the truth. 



In conclusion I should like to thank the firm of Messrs. Felton, 

 Grimwade, & Co. for permission to communicate the results of this 

 work, which was done in their research laboratory. 



