Agriculture Reference
In-Depth Information
months will accumulate more HMF than the same honey flash heated to 70° C for five
minutes and then cooled rapidly.
Temperature (ºC)
Time
30
100-300 days
40
20-50 days
50
4-10 days
60
1-2.5 days
70
3-5 hours
80
< 2 hours
Table 3.
Time for 30 mg/kg of HMF to accumulate (based on three samples).
Source: Kushnir and Subers (1964)
Detecting the level of HMF in honey
The following is a very rough but easy method of ensuring that your stored honey
is saleable or at least that it has a low level of HMF. This is accurate to within 95%
reliability and it is cheap. The test strips cost only 20p (approximately), although you
do have to buy them in packs of 25 minimum:
Mix 10 g of honey with 40 ml of
distilled
water at 20° C (i.e. room temperature).
Don't warm the liquid.
Leave the mixture for 1 hour, keeping it at the same temperature. The glucose
oxidase in the mix will give off hydrogen peroxide (H
2
O
2
).
Immerse a hydrogen peroxide strip (Merckoquant 110011 or 110081) into the
liquid for 1 second.
Wait for 15 seconds and then read off the colour against the colour scale. This scale
goes from 0 to 25 mg H
2
O
2
/per litre. The colour will indicate a number.
Multiply the number by 5. The result gives the amount of H
2
O
2
in micrograms
(µg) as determined by the glucose oxidase from 1 g honey in 1 hour at 20° C. For
