382 The Philippine Journal of Science uu 



Table III. — Samples collected near Malolos, January 10, 1918. 



No. 



Length 

 of stalk. 



Brix. 



Sucrose. 



Purity. 





cm. 





Per cent. 





1 



75 

 60 

 68 



10.7 

 11.7 

 10.6 



7.7 

 9.4 

 8.6 



72 

 81 

 81 



2 . 



3 





75 



1L7 



10.0 



85 



5 



90 



11.7 



9.4 



81 



6 



105 



12.6 



10.5 



83 



7 



75 



12.9 



10.5 



81 



8 



75 

 100 

 105 

 45 

 30 

 25 

 30 

 15 

 15 

 20 

 60 



13.1 

 13.8 

 13.6 

 14.3 

 12.9 

 12.6 

 13.8 

 14.7 

 14.3 

 12.9 

 16.8 



11.3 

 11.9 

 11.0 

 11.5 

 10.6 

 10.4 

 11.1 

 11.7 

 11.7 

 10.8 

 13.4 



87 

 86 

 81 

 80 

 82 

 83 

 80 

 80 

 82 

 84 

 80 



9 



10 



11 



12 



13 



14 



15 - - 



16 



17. 



18 



19 - 



15 



16.6 



13.3 



80 



20 



25 



15.0 



12.2 



82 





13.3 



10.9 



81.5 







From the above tables and other analyses 4 it may be definitely 

 stated that nipa sap as it issues from the palm is exceptionally 

 well adapted to the manufacture of sugar. The acids, waxes, 

 etc. of sugar-cane juice are absent, the sap is free from invert 

 sugar, contains no debris, and is colorless. If it were possible 

 to transport the tuba without deterioration due to inversion and 

 fermentation to a mill, no difficulty would be experienced in 

 producing white sugar. 



DETERIORATION OF NIPA SAP 



The inversion of sucrose and subsequent fermentation take 

 place very rapidly after the sap drops into the bamboo tuquils. 

 These are always exceedingly dirty, as no effort is made to re- 

 move the accumulation of slime and sediment adhering to the 

 interior. It could not be expected under these conditions that 

 a sucrose solution would long remain unchanged in a tropical 

 climate. However, nipa sap begins to invert within about four 

 hours after leaving the palm, even when collected in sterile 

 bottles. 



Gibbs 4 has shown that a zymogen is present in solution in the 



4 This Journal, Sec. A (1911), 6, 99-206. 



