— 71 — 



In some, but probably only isolated, instances, attempts are made to 

 reduce the loss in handling by distilling the expressed peel with water, 

 but, as stated, this method only yields an inferior oil. 



Recently, however, Patane and Carelli 1 ) have published a report on 

 a new method of working-up lemons which has been proposed by Pro- 

 fessors Peratoner and Scarlata. This process has been patented by the 

 two Professors and is published as an essay in the competition for the 

 prizes offered by the Agrumi- industry for the best solution of the problem. 

 It consists in cutting up the lemons into small pieces, and pressing them 

 so thoroughly that the juice, in exuding, carries with it the oil which is 

 liberated by the bursting of the cells in the peel. The acid liquid is then 

 subjected to distillation under diminished pressure at a distilling-tempe- 

 rature not exceeding 60°. The distillation-residue from which the oil has 

 been removed is worked-up for lemon-juice. 



Professors Patane and Carelli have applied their process experi- 

 mentally at the Chemico- Pharmaceutical Institute of the University of 

 Palermo, and have compared the results obtained by them with those 

 which they obtained by hand-pressure by the old method. Parallel-tests 

 yielded, by distillation 0,12 and 0,136%; by hand-pressure 0,115 and 0,16°/o. 

 So far as the yield is concerned there is therefore no very marked dif- 

 ference between the two methods. 



The idea of working at a low distilling- temperature is quite correct, 

 for when the oil evaporates between 50 and 60°, a temperature at which 

 not even the albumen in the cells coagulates, the distillate preserves the 

 pure aroma of the fruit. There will of course remain a slight, although 

 perceptible difference between the odour of this oil and that which has 

 been obtained by pressure, because the expressed oil contains several per 

 cent of non-volatile waxy substances in solution, which temper the sharp- 

 ness of the aroma. 



Being familiar with the injurious influence of high temperatures upon 

 the oils in question, we have for many years past only rectified lemon 

 oil, orange oil, and bergamot oil at the low temperature of 40 and about 50°. 



One objection, however, we must be allowed to make against the 

 process of Peratoner and Scarlata: the yield of oil is too low. In our 

 view it is a matter of prime necessity that, even if perhaps not all the 

 existing oil is recovered, at any rate the yield should be materially higher 

 than it is in the hand-pressing process which is now customary. On the 

 gther hand the simplification of the process, although it may also be 

 useful, is of decidedly secondary importance. 



With a view of obtaining positive information on the possibility of 

 an increased yield we have procured a large quantity of freshly-gathered 



x ) Bollettino del Ministero di Agricoltura, Industria e Commercio. Anno IX, Serie C, 

 Fascicolo 9, p. 21. 



