HONEY, ANALYSIS OF 
467 
Glucose 
per cent 
Honey 
per cent 
Direct 
Polariz. 
20% 
1 
Invert l 
at 20 
Polariz. 
at 87 
Polariz. 
difference 
between 
20 and 87 
Invert 
before 
inversion 
Sugar 
after 
inversion 
% glucose 
found by 1 
the above 
formula 
100 
+ 153.8 
+ 153.34 
+ 144.32 
30.02 
30.45 
50 
50 
+ 67.0 
+ 65.67 
+ 73.81 
8.14 
53.67 
54.50 
56.9 
20 
80 
+ 15.4 
+ 13.42 
+ 33.00 
19.58 
69.00 
70.35 
19.2 
10 
90 
— 2.4 
— 4.84 
+ 18.59 
23.43 
74.42 
74.12 
8.8 
5 
95 
— 11.5 
— 14.30 
+ 11.66 
25.96 
75.74 
77.80 
3.8 
3 
97 
— 14.2 
— 16.94 
+ 9.13 
26.07 
76.62 
78.01 
3.7 
2 
98 
— 16.0 
— 18.70 
+ 8.14 
26.84 
76.64 
78.34 
1.2 
i 
99 
— 18.2 
— 20.90 
+ 6.93 
27.83 
77.20 
78.87 
.0 
0 
100 
— 19.5 
— 22.11 
+ 5.94 
28.05 
77.68 
78.93 
.0 
liquid, and dissolve the dextrin in hot 
water, then treat with iodin. By this means 
as low as 2 per cent glucose can be de¬ 
tected. 
To determine the quantity of commercial 
glucose the following method by Browne 
gives fair results. It is better than other 
proscribed methods. 
METHOD FOR ESTIMATING GLUCOSE FROM 
THE POLARIZATION. 
The invert polarization at 20° is sub¬ 
tracted from the invert polarization at 87°, 
and the result multiplied by 77 (the aver¬ 
age per cent invert sugar after inversion in 
pure honeys). This product is divided by 
the per cent invert sugar after inversion 
found in the sample under examination. 
This figure is multiplied by 100 and the re¬ 
sult divided by 26.7. The result so ob¬ 
tained is the percentage of pure honey in 
the sample under examination. This per¬ 
centage subtracted from 100 gives the per 
cent glucose. 
The table at the top of page gives results 
by this method on mixture of honey with 
varying percentage of glucose. 
The percentages actually found agree 
fairly well with those added. However, it 
is not safe for the percentage of glucose 
in mixtures with less than 10 per cent. Its 
presence in small quantities is easily told 
thru the qualitative test described above. 
ENZYMES. 
Enzymes are bodies of varying chemical 
nature (considered to be albuminous in 
nature) which occur in the constitution of 
animals and plants and effect decomposi¬ 
tion of certain chemical compounds occur¬ 
ring in association with them without being 
used up themselves. They are all destroyed 
by high heat, but at lower temperatures are 
more or less affected. In honey, both in- 
vertase and diastase are present and are 
the principal ones. Invertase is capable of 
breaking up sucrose into dextrose and lev- 
ulose while diastase is capable of changing 
starch into dextrose. All honeys contain 
these enzymes. Boiling a honey destroys 
them. Heating a honey to 170° or 180° F. 
(a temperature above that recommended 
for liquefying a honey) destroys the action 
of invertase and weakens but does not de¬ 
stroy diastase. To destroy the activity of 
the latter it is necessary to bring the tem¬ 
perature up to 200° F. 
The test for enzymes is then important 
in assisting in the determination of adulter¬ 
ation with commercial invert sugar. A 
color reaction (See below Browne’s or 
Bryan’s modification of Fiehe’s test) and 
a positive diastase test would signify com¬ 
mercial invert sugar. 
The method of carrying on the test is as 
follows, “Moreau method.” 
Ten grams honey with 2 to 3cc. of water 
are added drop by drop, shaking constant¬ 
ly to 100 cc. absolute alcohol. Allow to 
stand, then decant, and add cold recently 
boiled distilled wmter to the precipitate and 
filter. Repeat this process on a second 10 
grams of the honey, boiling the filtered so¬ 
lution a few minutes. According to an¬ 
other method use the same amount of 
honey, but add 250cc. of 95 per cent alco¬ 
hol, shake and centrifuge, then wash the 
precipitate repeatedly with 75 per. cent al¬ 
cohol to remove all sugars, next dissolve in 
cold water and neutralize the solution to 
methyl-orange, using tenth normal sodium 
hydroxide, then add 1.5cc. of one per cent 
formic acid. 
The invertase is determined by adding 
5cc, of ten per cent sucrose solution to a 
