A UMF does not identify the compound in the honey responsible for the special anti-bacterial activity of manuka honey. Batches of manuka honey are tested and any batch with a potency equal to 10% phenol (carbolic) solution will be given the active 15+ designation. Ratings of 10 or higher is considered to be medical grade honey anything less is not considered as antibacterial activity to be appropriate for medical use. MGO readings are based on the ingredient methylglyoxal content which is responsible for the special anti-bacterial activity in the Active Manuka honey. With this compound present in the honey and MGO reading equals 30 or more will mean that the manuka honey is Active and can be used for medical purposes.