Most manuka honey sold today is raw or minimally processed. Unlike the regular honey you find on supermarket shelves, manuka honey typically isn’t pasteurized, because high heat would destroy the very compounds that make it valuable. That said, “raw” isn’t a regulated term, and not every jar of manuka honey meets the same standard. Understanding what happens between the hive and your shelf helps you know what you’re actually buying.
What “Raw” Actually Means for Honey
Raw honey comes straight from the hive with minimal intervention. A beekeeper filters out debris like bits of beeswax, pollen clumps, and other hive material, but skips the pasteurization step. Regular honey found in most grocery stores goes through pasteurization, which involves intense heating to kill yeast cells, improve appearance, and extend shelf life. The trade-off is that pasteurization destroys or reduces many of honey’s natural properties.
There’s no single legal definition of “raw” in most countries, which means producers can use the term loosely. For manuka honey specifically, the meaningful distinction isn’t just whether the label says “raw.” It’s whether the honey has been exposed to temperatures high enough to break down its signature compounds.
Why Heat Matters More for Manuka Honey
Manuka honey gets its strong antibacterial activity from a compound called methylglyoxal, or MGO. This is the molecule that sets manuka apart from other honeys, and it’s the basis for the MGO rating system printed on most jars. The problem is that MGO is sensitive to heat. Research published in Food Chemistry found that heating manuka honey to 90°C significantly decreased both MGO levels and another signature compound. The MGO reacts with naturally occurring amino acids in the honey, essentially being consumed by chemical reactions that accelerate at high temperatures.
This is a real, practical concern. Honey pasteurization can involve temperatures from 70°C to over 80°C sustained for 30 minutes to several hours. At those temperatures, the very compound you’re paying a premium for starts breaking down. Manuka honey candies processed at temperatures near 100°C have been found to contain wildly inconsistent MGO levels, ranging from mere traces to over 100 mg/kg, suggesting the heat destroys much of the original content.
This is precisely why most reputable manuka honey producers avoid pasteurization. Heating the honey would undermine the product’s core selling point.
Enzymes and Other Heat-Sensitive Components
Beyond MGO, honey naturally contains several enzymes, the most prominent being diastase, invertase, glucose oxidase, and catalase. These enzymes are fragile. Research shows that diastase activity drops steadily as temperature and heating duration increase. Gentle warming at 40°C to 60°C for a couple of hours has only a minor effect, which is why many producers warm honey just enough to make it pourable. But heating at 80°C for more than four hours can destroy diastase activity almost entirely.
The practical takeaway: manuka honey that has been gently warmed for bottling still retains its enzymatic activity. Honey that has been pasteurized at high temperatures for extended periods does not. Most quality manuka producers keep processing temperatures at or below 60°C for this reason.
How to Tell If Your Manuka Honey Is Truly Raw
One reliable chemical marker is a compound called hydroxymethylfurfural, or HMF. HMF forms naturally in honey over time, but levels spike dramatically when honey is exposed to high heat. The international Codex Alimentarius standard sets a maximum HMF limit of 40 mg/kg for honey (80 mg/kg for honeys from tropical regions). A low HMF level is a strong indicator that honey hasn’t been heavily processed. Some manuka brands include HMF testing results alongside their MGO ratings.
A few other things to look for:
- Texture: Raw manuka honey is typically thick, creamy, and slightly opaque. If it’s perfectly clear and runny like syrup, it may have been heavily filtered or heated.
- Filtration method: Quality producers use coarse straining, passing honey through a mesh to remove large particles while keeping beneficial components intact. This is different from ultrafiltration, which strips out pollen and other fine particles.
- MGO rating: A certified MGO or UMF rating on the jar means the honey has been independently tested. Since high heat reduces MGO, a verified high rating is indirect evidence the honey wasn’t overprocessed.
The Difference Between Raw and Unprocessed
Even raw manuka honey isn’t completely untouched. After extraction from the hive, it’s strained to remove debris, then gently warmed so it can be poured into jars. Some producers cream the honey, a controlled crystallization process that gives it a smooth, spreadable texture without adding heat. None of these steps compromise the honey’s beneficial compounds in any meaningful way.
What you want to avoid is manuka honey that has been pasteurized or blended with other honeys. Blending is a separate issue from heat processing, but it dilutes MGO concentration just as effectively. A jar labeled “manuka blend” or one without an MGO or UMF rating may contain only a fraction of actual manuka honey. Look for a monofloral manuka designation and a third-party tested MGO number to ensure you’re getting what you paid for.