U)lt) 



<il.l';AXIN(iS IN liKK (I 1/n UK 



259 



CHEMICAL COMPOSITION OF HAWAIIAN 

 HONEYS. 



BY W. P. KELI.Y. 



For many years the chemieal composition 

 of most products of commerce has, in a gen- 

 eral way, been known. In the manufacture 

 of some of these the entire process is subject 

 to the strictest control, and the finished prod- 

 uct made to conform very closely to a 

 given analysis. Included in the list of sub- 

 stances coming thus under chemical control 

 may l)e mentioned various food substances, 

 although theirchemical comi)osition former- 

 ly received only a general study. In recent 

 years, however, the chemical com})(isition of 

 foods has been more thoroughly investigat- 

 ed. It is a strange fact that while, for many 

 years, certain articles of connnerce received 

 the attention of expert analysts, a large per- 

 centage of the substances that go to form 

 human food were not so carefully investigat- 

 ed. The farmer, for instance, is much con- 

 cerned about the composition of tlie fertiliz- 

 ers which he api)lies to his fields, and often 

 quite exacting in his demands; l)ut the arti- 

 cles of food that he i)urchases are consumed 

 with little inquiry as to their makeup. The 

 average American has not taken the trouble 

 to inquire intothistjuestion. and in this con- 

 nection it may be stated that, at least until 

 recently, we as a nation were far behind the 

 more l)rogressi^•e Ki.n()))ean comitries in re- 

 gard to this i)oint. A general awakening of 

 the public conscience to a more intelligent 

 in([uiry concerning the ])urity of the sub- 

 stances of food, however, has led to a more 

 diligent and careful study of their chemistry. 

 Our Biueau of Chemistry of the Department 

 of Agriculture, led by the efficient direction 

 of Dr. H. W. Wiley, has devoted no small 

 l)art of its attention to this subject, and, as a 

 result, the American consumer is becoming 

 better acquainted with the comi)osition of 

 liis food stuffs. 



Among the food i)roductsthat'have receiv- 

 ed such attention may be mentioned honey, 

 although its conqjosition has, in a general 

 way, been known for many years. In bulle- 

 tin No. 110. of the Bureau of Chemistry, is 

 shown the chemical comixjsition of honeys 

 derived from a wide range of sources; like- 

 wise the sul)ject of Hawaiian honeys was re- 

 cently set forth in Bulletin Xo. 17 (if the Ha- 

 waii Experiment Station. From these and 

 other investigations it is evident that the 

 source from which honey is derived deter- 

 mines in a considerable measure its chemi- 

 cal comixisition. The differences between 

 the composition of nectar honey, such as 

 white-clover honey, alfalfa honey, and alga- 

 roba honey, are sliglit, being ])rincipally 

 those of color, aroma, and flavor; but the 

 composition of honey-dewhoney is striking- 

 ly different. 



There are small variations in the comiKisi- 

 tion of the same tyi)e of honey, as is shown 

 by analyses of samples drawn from differ- 

 ent places. This is due. in the main, to the 

 fact that the honev-bee does not conf'ne it- 



self wholly to any one source of nectar, and, 

 tlierefore, the a^■erage honey is a l)lend of 

 various nectars, and also usually contains 

 some honey-dew. As an a\erage of many 

 analyses, however, white-clo\er honey has 

 been found to contain the following }iercent- 

 age composition; Moisture, 17. OO per cent; 

 reducing sugar, 71.75 i)ercent; sucrose, 1.75 

 l)er cent; ash. .07 i)er cent; dextrine, .so per 

 cent; and free acid. .0(5 ])er cent. 



Honey derived from the nectar of alfalfa 

 contains 16.50 per cent moisture; 78.60 per 

 cent reducing sugar; 4.4 i)er cent sucrose; 

 .07 ))er cent ash; .;!4 per cent dextrine, and 

 .OS j)er cent free acid. The famous algarnba 

 honey, which is produced in such abundance 

 in Hawaii, has been found to contain 17.1 

 ])er cent moisture; SO.;! ])er cent reducing su- 

 gar; -1 per cent sucrose; .44 i)er cent ash; ;').57 

 l)er cent dextrine, and .1 i)ercent of free acid. 

 The aV)ove aiuilyses are for nectar honeys. 

 We will now consider the honey-dew tyi)e. 

 which is ])roduced so extensively in Hawaii. 

 This has been found to contain about 15.5 

 ])er cent moisture; 62.1 per cent reducing 

 sugar; 5.25 i)er cent sucrose; 1..'! per cent 

 ash; 10 per cent dextrine, and .15 })er cent 

 free acid. From theconq)arison of tlie abi)\e 

 figures, it is a])i)arent that honey-dewhoney 

 is (juite unlike nectar honeys in chemical 

 conq)osition. containing considerably less 

 reducing sugar, and \ery much more ash, 

 dextrine, and sucrose. 



There are, however, still greater differ- 

 ences between nectar honeys and honey-dew 

 honeys than are shown by the above analy- 

 ses. When i)olarized light i)asses through a 

 solution of nectar honey at a tenq)erature of 

 2<) degrees it is usually rotated to the left, 

 while lioney-dew honey rotates the jilane of 

 polarized light to the right. After nectar 

 honey undergoes "inversion," as it is called 

 in chemistry, rays of ])olarized light i)ass!ng 

 through its solution are again rotated to the 

 left at a tenq)erature of 20 degrees; while 

 honey-dew honey, on the other hand, con- 

 tinues to rotate to the right after inversion. 

 lUght-handed polarization in honey has long 

 l:)een regarded as evidence of adulteration 

 with commercial glucose or sucrose; but in 

 the case of lioney-dew honey this ex])lana- 

 tionwill not hold for its right-hand polariza- 

 tion, since samjiles of known origin, and 

 those free from adulteration. ])osse.ss tliis 

 characteristic quality. Its ex])lanation is 

 foimd in the high percentageof dextrineand 

 other gummy-like IXKlies which are always 

 found in honey-dew honey. 



Xotwithstanding the material ditference 

 in chemical comi)osition between honey-dew 

 honey and nectar honey, botli are natural 

 products, collected and stored by the hoirey- 

 bee, and as such are free from adulteration 

 in the usual sense of the word, and may. 

 therefore, be used without fear of their con- 

 taining commercial glucose or other added 

 sugars. 



Algaroba is tlie source of one of the most 

 beautiful honeyson the market. It isalmost 

 white in color, and ])ossesses a very delight- 

 ful flavor and aroma; and, although it is but 



