UMF, MGO, and the rest

The UMF system

The Unique Manuka Factor (UMF) is a quality trademark managed by the UMF Honey Association (UMFHA) in New Zealand. It grades Manuka honey on a scale that combines three chemical markers:

Methylglyoxal (MGO) — the primary antibacterial compound
Leptosperin — an authenticity marker unique to L. scoparium nectar
Hydroxymethylfurfural (HMF) — a freshness and quality indicator (must be below 40 mg/kg)

A UMF rating of 10+ means the honey has been independently tested and meets minimum thresholds across all three markers. Higher numbers indicate higher MGO concentrations.

The MGO system

Some producers grade by MGO concentration alone, measured in mg/kg. This is a direct, transparent measurement — but it tells you nothing about authenticity (leptosperin) or freshness (HMF). A honey labelled "MGO 400+" contains at least 400 mg/kg of methylglyoxal, roughly equivalent to UMF 13+.

How they compare

UMF	MGO (mg/kg)	Tier	Typical use
5+	83+	Table	Daily sweetener
10+	263+	Everyday	Immune support
15+	514+	Active	Throat, skin
20+	829+	High-potency	Clinical
24+	1,122+	Ultra	Therapeutic

What to watch for

Not all grading is equal. Look for the UMF trademark (independently verified) or MGO certification from an accredited lab. Claims like "bio-active" or "raw" without a specific MGO or UMF number are marketing, not science.

Hana Sterling

Frequently asked questions

What's the difference between UMF and MGO grading?

UMF is a trademark managed by the UMF Honey Association in New Zealand that combines three markers — methylglyoxal (MGO), leptosperin, and HMF — into a single quality grade. MGO grading uses methylglyoxal concentration alone, in mg/kg. UMF tells you about authenticity and freshness as well as potency; MGO alone tells you only the antibacterial concentration.

What MGO concentration is equivalent to UMF 10+?

UMF 10+ corresponds to roughly 263 mg/kg of methylglyoxal. UMF 15+ is about 514 mg/kg, UMF 20+ is about 829 mg/kg, and UMF 24+ is about 1,122 mg/kg.

Why does leptosperin matter?

Leptosperin is an authenticity marker unique to Leptospermum scoparium nectar — it's how UMF certification distinguishes real Manuka honey from blends or counterfeits. MGO grading on its own does not check for it.

What is HMF and why is it tested?

Hydroxymethylfurfural (HMF) is a marker for freshness and storage conditions. UMF certification requires HMF to remain below 40 mg/kg. High HMF can indicate excessive heat exposure or long storage.

Are 'bio-active' or 'raw' claims meaningful without a UMF or MGO number?

No. Without a specific UMF rating or MGO concentration backed by an accredited lab, these terms are marketing language rather than verifiable potency claims.