Compare honey authenticity tests

12 methods, in no order of merit.

• Stable carbon isotope ratio analysis (SCIRA, EA-IRMS (AOAC 998.12))

  Status: Official method

  Can support

  • Addition of sugar from C4 plants such as cane and maize, at about 7% of the honey or more

  Cannot alone establish

  • That no syrup was added: syrups from C3 plants such as rice, beet and wheat have carbon isotope ratios close to nectar's and are not detected
  • C4 addition below the method's level of detection
  • The honey's floral or geographical origin

  Depends on

  • The protein extracted from the same honey, used as its internal standard
  • Syrups not engineered to match honey's isotope ratio — such syrups are on the market

• Isotope analysis of individual sugars (LC-IRMS)

  Status: Validated in peer-reviewed work

  Can support

  • C4 sugar addition at lower levels than bulk analysis, by comparing the isotope ratios of the honey's individual sugars

  Cannot alone establish

  • Addition of C3 syrups whose sugars carry nectar-like isotope ratios
  • Origin of any kind

  Depends on

  • Chromatographic separation of the sugars before the isotope measurement
  • Reference ranges for the differences between sugars in genuine honey

• Sugar profiling (HPLC, GC)

  Status: Official method

  Can support

  • Whether the sugars meet the compositional limits — fructose plus glucose, sucrose
  • A sugar balance unusual for the declared honey type

  Cannot alone establish

  • Absence of syrup: syrups are now made to mimic honey's sugar composition
  • That an unusual profile is fraud — some honeys are naturally high in sucrose or low in fructose

  Depends on

  • Published compositional limits and typical values for the honey type

• Syrup marker screening (HPAEC-PAD, LC-HRMS (targeted))

  Status: Screening technique

  Can support

  • The presence of markers of manufactured syrup — mannose, foreign oligo- and polysaccharides — that genuine honey is not expected to contain

  Cannot alone establish

  • How much syrup was added: the markers say present or absent
  • Absence of syrup: a syrup without the markers sought passes
  • On its own, a regulatory finding: the Commission describes these methods as useful for suspicion and not yet validated

  Depends on

  • A library of known syrup markers, which lags each new syrup
  • Knowledge of which oligosaccharides occur naturally in which honeys

• Nuclear magnetic resonance profiling (1H-NMR)

  Status: Screening technique

  Can support

  • That a sample's profile is unusual compared with authentic honeys described the same way
  • Classification by type or origin, within the scope of the reference set

  Cannot alone establish

  • Adulteration or a false origin on its own: an unusual profile has innocent causes, and a rare genuine honey can sit outside the reference set
  • Anything about honeys the reference set does not represent

  Depends on

  • A reference database of authentic honeys — its scope, representativity, metadata and validation
  • The statistical model built on it, and whether that model was tested on samples it had not seen

• Untargeted metabolomics (LC-HRMS (untargeted))

  Status: Experimental or emerging

  Can support

  • Discovery of candidate markers for a honey type or region
  • Classification of samples by a model, in the study that built it

  Cannot alone establish

  • A routine finding: most classifiers have been built and tested on one study's samples
  • Origin for honeys, regions or years outside the training samples

  Depends on

  • The training samples, the instrument and the processing settings
  • External validation on independent samples, which many studies lack

• Infrared and Raman spectroscopy (NIR, MIR/FTIR, Raman)

  Status: Screening technique

  Can support

  • Rapid first-line sorting of samples by type or origin, for follow-up

  Cannot alone establish

  • Adulteration or origin on its own: pure and adulterated honey give similar spectra, and the result is only as good as the model
  • A finding about a portable or one-off reading without laboratory confirmation

  Depends on

  • A calibration model and the reference samples behind it
  • The instrument and its calibration, which do not transfer automatically between instruments

• Pollen analysis (Melissopalynology)

  Status: Validated between laboratories

  Can support

  • Whether the pollen spectrum fits the declared floral source, read with sensory and physico-chemical results
  • That a pollen assemblage contradicts a declared region
  • That pollen has been largely removed

  Cannot alone establish

  • A plant's share of the nectar from its pollen share: some plants are over-represented in honey pollen and others under-represented
  • The country of origin on its own: it shows which plants the bees met, and many grow in more than one country
  • Anything after heavy filtration has removed the pollen

  Depends on

  • An analyst who knows the regional flora, and a reference collection of pollen types
  • Honey-type-specific criteria: there is no single pollen percentage that makes every honey monofloral

• DNA metabarcoding (NGS)

  Status: Experimental or emerging

  Can support

  • Which plant taxa are present, complementing microscopy
  • Detection of taxa that are hard to tell apart by pollen shape

  Cannot alone establish

  • Each plant's share of the nectar: read counts reflect DNA extraction and amplification, not nectar contribution
  • Taxa present at low levels, which are less likely to be detected
  • Authenticity in general, or a substitute for pollen microscopy

  Depends on

  • Sequence reference libraries for the region's flora
  • DNA that survived processing, filtration and storage

• Elemental and trace-element profiling (ICP-MS, ICP-OES)

  Status: Single-study research

  Can support

  • That a sample's elemental profile fits, or does not fit, authentic samples from a claimed region

  Cannot alone establish

  • That one element proves one country: elements reflect the plant as much as the soil, and regions overlap
  • Origin where no authentic samples from the region exist to compare against

  Depends on

  • Authentic regional reference samples, which for much of the world do not exist
  • Freedom from contamination: tools and galvanised storage can add iron and zinc

• HMF and enzyme activity (HMF, diastase, invertase)

  Status: Official method

  Can support

  • Heating or long or warm storage, where HMF is high and enzyme activity low
  • Compliance with the compositional limits for HMF and diastase

  Cannot alone establish

  • Adulteration: high HMF is a heating and storage indicator, not proof that a honey is fake
  • Origin of any kind

  Depends on

  • The honey's age and storage temperature, and its natural enzyme level, which is low in some genuine honeys

• Water content (Refractometry)

  Status: Official method

  Can support

  • Whether the honey is within the water limit, and so how likely it is to ferment

  Cannot alone establish

  • Authenticity: water describes ripeness and keeping, and some genuine honeys, heather among them, are naturally high
  • That a fermenting honey is fraudulent: fermentation is a condition, not evidence of fraud

  Depends on

  • A calibrated refractometer and temperature correction

Sources: Methods for verifying honey authenticity; AOAC Official Method 998.12 — C-4 plant sugars in honey: internal standard stable carbon isotope ratio method; Frequency of honey adulteration; Standard for Honey (CXS 12-1981); Adulteration of honey; Detection of honey adulteration by liquid chromatography–high-resolution mass spectrometry: results from an EU coordinated action; EU coordinated action 'From the Hives' (honey 2021–2022); Framework for interrogation of honey authenticity databases (IHAD); The use of SPME-GC-MS, IR and Raman techniques for botanical and geographical authentication and detection of adulteration of honey; Harmonized methods of melissopalynology; Using DNA metabarcoding to identify the floral composition of honey: a new tool for investigating honey bee foraging preferences; Honey: inorganic composition as possible marker for botanical and geological assignment; Directive (EU) 2024/1438 amending the 'breakfast directives', including honey. The method guide explains each in depth: How honey is tested.