PART II. CHEMICAL COMPOSITION OF HAWAIIAN HONEYS. 



By Alice R. Thompson. 



During 190G forty-nine samples of Hawaiian honeys of known 

 origin were collected by the station entomologist and analyzed by 

 the writer. The honeys consisted of two t}^pes, a floral and a honey- 

 dew product. As explained in Part I of this bulletin (p. 9), the 

 floral honey is derived mainly from the flowers of algeroba and the 

 honey dew is chiefly a secretion of certain insects in the sugar-cane 

 fields. The composition of these two types and the natural mixtures 

 of them were determined and compared. The source, general char- 

 acter, and composition of the honeys examined are shown in the 

 table on the next page. 



ALGEROBA HONEY. 



The composition of algeroba honey, as determined in the laboratory, 

 resembles that of a normal honey with the exception of its high ash 

 content. The ash varies between 0.44 and 0.59 per cent, while ac- 

 cording to the present official standard a pure honey should not exceed 

 0.25 per cent. 



An analysis of a sample of algeroba honey (sample No. 43) gave 

 0.446 per cent of ash, containing potash 0.258, phosphoric acid 0.008, 

 calcium 0.013, magnesia 0.004, alumina 0.003, and chlorin 0.003 per 

 cent. 



As is seen from the analysis reported on page 9, this honey meets 

 the requirements of the standard with the exception of the ash. Its 

 direct polarization is to the left ; its indirect polarization deviates 

 only a few degrees further to the left ; at 87° C. its polarization is but 

 slightly to the right ; the sucrose content is low and the percentage of 

 reducing sugar is high. The acidity (0.064 per cent, calculated as 

 formic acid) was found to be low. On addition of methyl alcohol to 

 the honey the precipitate formed was but 0.23 per cent. In another 

 honey of the same type whose direct polarization was — 18.4 the pre- 

 cipitate amounted to 0.195 per cent. The precipitate was slightly 

 soluble in water and the solution of the soluble part, made up to 



Bui. 17 



(13) 



