1901.] 



H. H. Mann — The Enzymes of the Tea L^.a/. 



163 



The amount of oxidase in A is here regarded as unity, and its type of 

 plant was " China", and all figures are given on the dry matter of the 

 leaf as plucked for manufacture. In each case a much larger amount of 

 enzyme was present in the leaf which made the better tea. 



From Garden B, I had three samples of leaf. No. 1 was from young 

 " Assam" plant producing excellent tea, No. 2 was from a low level 

 extension also of " Assam" plant but giving the worst tea in the garden 

 though still quite as good as the district average, No. 3 was from 

 *' China" plant producing tea of very high quality. Comparing, in pre- 

 cisely the same manner as above, all these samples of leaf with that from 

 garden A the following figures were obtained : — 











Relative amount of active 



Relative amount of 



active 











enzyme. 



enxyme. 











A. 



1-00 



1-00 





B. 



No. 



1 ... 





1-88 



103 





B. 



No. 



2 ... 



... 



1-17 



1-32 





B. 



No. 



3 ... 





1-83 



1-32 





In this case again it appears that the quality varies with the quantity of 

 ferment present in the leaf in an active form. It will be noticed that 

 the various amounts of enzyme are much closer together when the total, 

 including the supposed pro-enzyme, is considered, than when the active 

 form only is taken into consideration. It may well be that this difference 

 is a real one, and that there is some cause in certain places from soil, 

 climate or other consideration which may prevent the formation of 

 active enzyme, and such a cause would affect the quality. 



Another point remains in this connection. What effect has withering 

 on the amount of ferment ? The answer to this question has been exceed- 

 ingly interesting, and seems to indicate that this operation possesses a 

 function in the manufacture hitherto quite unsuspected, and which 

 leads to a very different conception of the process to that hitherto held. 

 The leaf from gardens A and B above considered, were allowed to 

 wither, and taking full account of the corresponding loss of moisture, 

 the enzyme again determined. Taking the oxidase in the fresh leaf at 

 garden A as unity (that is to say that the unit in the last table is the 

 same as unit in the following) we have :— 



1 



Relative amount 

 of active 

 enzyme. 



Percentage 



increase 



during 



withering. 



Relative total 

 amount of enzyme. 



Fercentage 



increase 



during 



withering. 



A. 



B No. 1 

 B. Na. 2 

 B. No. 3 



181 

 2-49 

 1-88 

 2-19 



sro 



319 

 60-7 

 197 



1-69 

 187 

 1-87 

 2-19 



69-0 

 43-8 

 41-6 

 65-9 



