Changes in Quality of Honey Caused by Heating and Storage

Part II. Changes in diastatic activity (diastase number: DN) of honey

Abstract

Changes in diastatic activity of different honey samples during heating and storage were examined.
(1) Diastase numbers of domestic, imported and commercial honey samples were measured.
(2) Changes in diastase number (DN) of honey samples during heating at 50, 60, 65 and 70°C were investigated. At 65°C they showed a low DN already after 3 hours, while at 50 and 60°C their DN did not show any significant change after 10 hours, although they reached a low level after one or two days.
(3) Many honey samples showed DN less than 8 when stored at 36°C for about 5 months. When stored at room temperature, their DN decreased slightly. Change in DN was variable depending on the kinds of honey samples. Samples showing a high pH level and a strong buffering action were found to show relatively slight decrease in DN.
(4) Based on the results it was concluded that the DN of honey sample can be used as a criterion of the extent of addition of quasi-honey as well as the extent of heating of the sample.