Screening method for the determination of peroxide acumulation in honey and relation with HMF content
J D Kerkvliet
A fast semiquantitative screening procedure is described for the determination of peroxide activity in honey. Upon dilution of honey with water, hydrogen peroxide is released by the action of the enzyme glucose oxidase. After 1 h incubation time at 20°C, one peroxide test strip (Merck) is dipped into the honey solution for one second and the blue colour obtained is read after 15 s by means of the colour scale. The obtained value, multiplied by five, gives the amount of hydrogen peroxide in micrograms per g honey per hour at 20°C. A zero value may result from heated honey or prolonged storage by low natural enzyme content, by chemical interactions or by the action of the enzyme catalase. Vitamin C (ascorbic acid) also reduced hydrogen peroxide formation. After analyzing about 500 honey samples, it was found that if the peroxide accumulation was ≥ 10 µg/g/h (20°C) HMF was ≤ 40 mg/kg and/or the diastase index was ≥ 8 with a probability of 95%.