In a nutshell, well-stored Manuka Honey and most other honey never expires or spoils, even if its been previously opened. In fact, it's recognized as the only food that doesn't spoil.
Good storing conditions means out of direct sunlight, not exposed to direct heat
and isn’t frozen – in these conditions, your manuka honey will last well beyond it’s best before date.
So why is there a best before date on Manuka Honey jars if the honey doesn’t expire?
The best before date indicated on the jar is there as a food industry standard. The preferred date of consumption must appear on the packaging for any food items. Also, over time the honey might change its visual appearance, but it is still safe to eat.
Why Manuka honey doesn’t go bad?
Manuka Honey is antibacterial, which means nothing funky is going to grow in your manuka honey. Manuka Honey also has a low pH of about 3-4.5 - an environment bacteria doesn’t like.
Incorrectly Stored Honey and exceptions
When you don’t store honey properly, you risk lowering its antimicrobial properties. This will lead to contamination and degradation of the honey. When honey is left exposed to sunlight, its water content will increase, giving the microbes the resources to grow and multiply.
Other contamination by moisture can occur by directly adding moisture to your honey while consuming it.
Granulation and crystallisation can also lead to increase in moisture. That is another reason why our Manuka Honey is creamed. Once the honey changes state from liquid to creamed it will not crystallize or granulate.
And just we like it, scientific evidence why bacteria doesn't grow in Manuka Honey
Extract from NIH.gov article: "The production of Manuka honey as well as the storing process account for the presence of microorganisims. Most of these organisms are said to be in inactive forms as they can hardly survive in honey because of manuka honey's several properties including hygroscopicity, hyperosmolarity, acidity, peroxide content, antibiotic activities etc.
While honey easily gets contaminated during the process of its production by bees and microorganisms also get introduced into honey by activities of man including equipment, containers, wind and dust, the status of the microorganisms found in honey is dormant. It is the spore forming microorganisms that survive in honey by remaining dormant i.e suspended without growth.
Non-spore forming bacteria i.e. vegetative forms are not normally present in honey because they cannot survive. Ten species of non-spore forming intestinal bacteria inoculated into pure honey survived only a few hours. It is possible therefore to assert that the microorganisms found in honey undergo gradual extinction in honey due to its inhibitory properties as highlighted earlier in this discourse.