What moisture, HMF and diastase actually mean

Every DAY21 batch page publishes a set of laboratory figures. This page explains what each one measures, so the numbers are useful to you rather than decorative.

Moisture (%)

What it measures: the water content of the honey.

Why it matters: honey resists spoilage because it is too dry for most microorganisms. Above roughly twenty percent, naturally occurring yeasts can ferment it. Below that, honey is effectively shelf-stable indefinitely.

What a good figure looks like: premium Sidr is typically well under seventeen percent. Lower generally indicates honey that was left in the comb until the bees capped it, rather than harvested early.

The caveat: low moisture can also be achieved industrially, by drying honey that was harvested wet. Moisture alone does not prove careful harvesting. Read it alongside HMF and diastase, which is where industrial processing usually shows up.

HMF (mg/kg)

What it measures: hydroxymethylfurfural, a compound that forms as sugars break down.

Why it matters: HMF is close to zero in fresh, unheated honey and rises with heat and with time. It is the single most useful indicator of whether honey described as raw has in fact been heated — commonly done to delay crystallisation, ease filtration, or reduce moisture after an early harvest.

What a good figure looks like: lower is better. Internationally, forty milligrams per kilogram is a widely used upper limit for honey, with a higher allowance for honey from hot climates. Good fresh honey sits far below that.

The caveat: HMF rises slowly during normal storage, particularly in warm conditions. A moderately elevated figure in older honey is not necessarily evidence of heating. The date of the test matters, which is why we publish it.

Diastase (Schade units)

What it measures: the activity of diastase, an enzyme bees add to nectar.

Why it matters: enzymes are fragile. Diastase degrades with heat and with age, so it is the mirror image of HMF: heating pushes HMF up and diastase down. The two together are far more informative than either alone.

What a good figure looks like: higher is better. Eight Schade units is a common international minimum. Well-handled raw honey commonly reads considerably higher.

The caveat: natural diastase content varies by floral source. Some genuinely raw honeys are naturally low. This is a reason to read it in context rather than as a pass mark.

Pollen analysis

What it measures: the proportion of pollen grains from each plant species, counted under a microscope.

Why it matters: this is what establishes that Sidr honey is actually Sidr. A high proportion of Ziziphus spina-christi pollen indicates the bees were foraging predominantly on Sidr. A low proportion indicates they were not, regardless of what the jar says.

What a good figure looks like: a dominant Ziziphus percentage. We publish the actual figure rather than the word 'monofloral'.

C4 sugar (IRMS)

What it measures: isotope-ratio mass spectrometry detects the distinct carbon signature of sugars from C4 plants — cane and corn.

Why it matters: cutting honey with cane or corn syrup is the most common and most profitable form of adulteration. This test is how it is caught.

What a good result looks like: a pass. This is a gate, not a score. Honey either shows evidence of C4 sugar adulteration or it does not.

Safety panel

What it measures: screening for antibiotic residues, pesticides and heavy metals.

Why it matters: these relate to how hives were managed and where they were sited, and they are not detectable by any other means.

What a good result looks like: a pass on every parameter.

Total phenolic content (mg GAE/kg)

What it measures: the concentration of phenolic compounds, expressed as gallic acid equivalents.

Why it matters: it is a compositional measurement, and it varies meaningfully between honeys.

An important note: we report this as composition only. UAE regulation governs health and nutrition claims on both labels and advertising, and we do not describe physiological effects of any figure on this page. A measurement is a fact about the honey. A claim about what it does to you is a different kind of statement, and one we do not make.

Reading a batch page

No single figure carries the verdict. Read them as a set: pollen establishes what the honey is, C4 establishes that nothing was added, moisture indicates how ripe it was at harvest, and HMF and diastase together indicate whether it was heated afterwards. A batch that reads well on all five was harvested carefully and handled carefully.