Extract from The Straits Times, 22nd August 2017
In 2015, archaeologists reported that while excavating tombs in Egypt, they had found 3,000-year-old honey and it was perfectly edible.
This durability is due to the unique features of honey. As it is low in water content and high in sugar, bacteria cannot thrive in it.
Honey also contains small amounts of hydrogen peroxide which inhibits the growth of microbes. This is partly why bees produce it for the young - it is both food and protection.
Processing honey also helps as the sugars in honey are hygroscopic and tend to draw in atmospheric water, which is not ideal.
However, during processing and packaging, the heat treatment first removes water and then airtight lids keep the water out, helping it keep for a longer time.
Honey can go cloudy and crystallise when opened, as the sugars draw in water again, but physical change can be reversed by simply warming the honey.