About us | Advertise with us | Contact us
Posted: 9 December 2015 | Stephan Schwarzinger, Felix Brauer and Paul Rösch, Research Center for Bio-Macromolecules, University Bayreuth, ALNuMed GmbH / Bernd Kämpf, FoodQS GmbH, Markt Erlbach |
Honey – for thousands of years it has been the only source of sweet taste
and it still is the prototype of an all-natural
In particular with the growing trends for organic food and a healthy life-style honey has enjoyed steadily increasing popularity
The reasons for this are complex and interwoven and have their origin in bee diseases
climate change as well as agro-industrial production methods
an increasing number of honeys mixed with non-natural sweet syrups has been detected in the international trade
Such economically motivated adulteration is seen also in other foods such as fruit juice
and it is most reliably exposed by NMR-profiling
This technology is based on the comparison of hundreds of spectral features of authentic honeys with the sample to be tested…
Owed to its special role as sweet food in the development of mankind
honey today enjoys special protection by the law1
serious issues in honey production complement the rise in the demand for honey
including the Varroa mite putting stress on bee colonies by transferring other bee pathogens and the intensification of agricultural production with an escalating use of fertilizers
have led to a phenomenon called colony collapse disorder (CCD)
CCD resulted in losses of more than 80% of the hives in certain cases in the past years2
the changing climate impacts honey production
when long periods of rain in the flowering season resulted in a complete loss of production in some European countries
Economically motivated adulteration on the rise Production shortages lead to price increases
which in turn give rise to a growing number of adulterated honeys in the market
In the particular case of honey the authentic product is diluted with various sugar syrups
which are produced at industrial scales from
or wheat at a fraction of the price of honey
or products with the pollen being removed are strictly forbidden in the European market
but are accepted elsewhere and thus participate in global trade
Economically motivated adulteration not only includes mixing of honey with cheap syrups
but extends to disguising the geographic origin of a particular honey
Honey laundry became public recently in the ‘Honeygate’ scandal in the USA
where honey from China was wrongly declared on a large scale to obfuscate its country of origin
Lost excise duties were rumoured to be as high as USD 180 million3
To further obscure the product’s geographical origin – typically tested by analysing the pollen spectrum – pollen is now increasingly being filtered out of the honey
which – on the other hand – is simple to verify
Counterfeiting honey with plant-derived sugar syrups
honey consisting mainly of the two mono-saccharides glucose and fructose is adulterated with its main constituents
exhibit a different ratio of the stable isotopes of carbon
which can be proven by stable isotope ratio mass spectrometry (IRMS)
a method routinely used in honey analysis4
and other C3-plants cannot be detected by the same method
typically a combination of several analytical methods is applied today that includes IRMS
enzymes used in industrial syrup production
as well as small molecule markers for foreign syrups
dedicated substances can be used to test for authenticity requiring a set of different analytical techniques
All this takes a lot of time and is costly; more complex issues such as those involving a food’s provenance
cannot be answered at all by only quantifying a limited set of substances
authenticity and unveil adulteration in just one measurement
Remedy is provided by nuclear magnetic resonance (NMR) spectroscopy
a technique that is also applied in medical imaging (MRT)
which typically focus on the detection of specific
pre-selected markers (‘targeted analysis’)
an entire spectrum of the ingredients of the sample is recorded
high-resolution NMR spectroscopy permits the ‘non-targeted’ detection and – at the same time – quantification of typically several dozens of substances within a single measurement
the method is predestined for the efficient analysis of complex substance mixtures as found in food: unlike methods using
no time-consuming separation of the components in a mixture is required
the sample can also be measured without extensive chemical preparation (e.g
due to its unique dynamic range the reproducible retrieval of signals arising from substances at very low concentrations (ppm range) in the presence of highly concentrated compounds (% range) is possible
Since the plants are genetically identical
the same ingredients are to be expected in both cases
in the form of the plants’ metabolic products (metabolites)
Yet variations in climate and soil quality will lead to relative differences in concentration
the systematic differences in concentration of a range of metabolites can be aggregated into a pattern
which can be used as a marker for geographical origin or the absence of unlawful adulterations
the NMR-spectrum of an unknown sample can be compared with spectra from authentic reference samples by automatic methods
These mathematical procedures can then be used to classify new and unknown samples by comparison with the reference database
The procedure is already routinely used in the FoodScreenerTM (Bruker BioSpin
Germany) for fruit juice (SGF-ProfilingTM) and wine (Wine-ProfilingTM)
where a significant number of quantitative quality parameters required by regulatory bodies are obtained5
and processing can be recorded in full automation during a measurement time of just 15 minutes
Also in the case of honey NMR spectroscopy offers a versatile multi-parameter screening tool to test for quality
and adulteration with minimal time effort and cost
Precondition for such analysis is the establishment of a sufficiently large reference spectra database of material with proven authenticity
A consortium of several analytical laboratories specialised in honey analytics and the NMR-based instrument maker and solution provider Bruker BioSpin worked together to develop this database as major part of the new the Honey-ProfilingTM which works on the base of the well established FoodScreenerTM platform
Conventional analytics had been used to support conformity of data base entries
methods included mellisopalynology (pollen analysis) to verify botanical variety and geographical origin
classical quality parameters such as glucose
as well as the classical methods for detection of adulteration as above
A total of up to 18 different parameters were determined for each authentic sample
To ensure creation of a sufficiently large database covering many floral varieties as well as worldwide origins the Honey-Profiling consortium had to undertake an unparalleled collaborative effort in the honey business
to establish statistical models for discriminating adulterated from authentic samples a suitably large number of adulterated samples is required
a large number of samples were mixed with syrups and bee-feed at defined levels
the Honey-ProfilingTM Consortium has measured several thousand honeys
including comprehensive supplementary conventional analysis
This way a previously unmatched coverage of the natural variation of ingredients of authentic honey can be defined
which is indispensable to define the ingredient profile of authentic honey
The acquired knowledge builds the foundation for establishing a positive definition of how authentic honey should look like
Any deviation from the patterns found in the database that does not match any variety or geographical origin might be an indication for an adulteration
Inclusion of samples from different years of vintage secures that the statistical models generated are generally applicable
The large scatter in geographic origins further ensures that a large variety of poly-floral patterns are represented in the database
even annual changes in floral composition in a honey are covered
which may be due to climate change or changes in agro-culture
are surveyed by annual updates of the database by the members of the Honey-ProfilingTM consortium
at the same time leading to an increase of coverage by the database
For Honey-ProfilingTM a remote data analysis concept was established located and maintained by Bruker BioSpin
where the NMR spectrum of the samples is recorded at the user’s site and remotely evaluated has proven to be successful already in the case of fruit juice and wine testing: To ensure comparable and robust analytical results
both the modules for statistical testing as well as for targeted direct quantification of substances are also carried out as server-based services by Bruker BioSpin
which results in a straightforward interpretation of the data for the user
also allows fast implementation of new statistical models and targeted parameters as these become available
These central modules for quantification as well as the untargeted statistical testing for origin
and adulteration were accredited as apart of the Bruker BioSpin laboratory’s flexible accreditation early in 2015 according to the ISO 17025 standard for fruit juices
and also honey and are available to FoodScreenerTM platform users
For comparison of NMR spectra generated by third-party laboratories reproducibility of the spectra is of utmost importance as well as ease of operation
Honey is dissolved and samples were mixed with Bruker BioSpin Wine-Profiling buffer
and the pH was precisely adjusted utilizing an automated Bruker pH titration unit
NMR spectra are obtained by a standardized FoodScreenerTM platform from Bruker BioSpin
The system is operated in a push-button mode and automatically takes over all necessary steps for obtaining reproducible high-quality spectra
The system is under full control of a LIMS system which controls operation of the NMR spectrometer and communicates with the server at Bruker BioSpin
It is of pivotal importance to judge a honey by several criteria simultaneously
which Honey-ProfilingTM provides from a single measurement and in an automatically generated report interpretable by the food specialist
This shall be demonstrated in three examples
we demonstrate the power of Honey-ProfilingTM to verify a given country of origin
This is of growing importance as the country of origin is increasingly used in marketing and declared on the honey jar label
In many countries – if declared on the label – the honey must exclusively originate from this named country
when a non-EU honey is used in a blend this honey must not be labelled as originating from EU countries
Figure 1 (page 00) depicts an excerpt of the report for a honey
where the supplier has claimed Bulgaria as country of origin
first testing for the region of origin (here Europe)
the honey’s NMR profile is compared with authentic samples from the claimed country of origin
It can clearly be seen in the traffic-light summary of the report (Figure 1A) that the country of origin claimed does not match the reference database
the country of origin is not Bulgaria (Figure 1C)
Experience shows that falsely declared origin often is accompanied by additional manipulations
Honey-ProfilingTM also allows testing for the variety without the need of pollen analysis
a blossom honey labelled as honeydew can easily be detected (Figure 2
Not only statistical classification immediately identifies the fraud (Figure 2B)
Honey-ProfilingTM also provides numerous quantitative parameters strengthening the overall analysis
The comparison with the distribution of a parameter being looked at in comparison with the reference database has proven particularly useful
It can clearly be seen that concentrations for glucose and the sum of glucose and fructose are too high in comparison with all other honeydew honeys
while turanose concentration is too low when compared to the reference distribution for honeydew honey (Figure 2C)
At present Honey-ProfilingTM can classify honeydew and poly-floral honey as well as mono-floral varieties
which due to its anti-bacterial activity reached high prices in the market
specific marker compounds correlating with the value of this honey (MGO
phenyllactic acid) are determined allowing rapid analysis of this expensive honey
Testing for adulteration can also be done without this information as shown in Figure 3
The poly-floral honey tested was supplied without further information about its possible origin
the traffic-light summary of the Honey-ProfilingTM report immediately signals a possible addition of syrup
By systematic comparison of the ratio of a large number of NMR signals in authentic and proven adulterated honeys
a set of indices was derived that indicates adulteration
a corresponding remark is made in the report
which are absent in all authentic honeys (or vice versa)
are detected in the course of univariate analysis
the corresponding region in the spectrum is reported (Figure 3B)
In most cases of addition of syrup clear indications can be found in the spectra
such as the presence of elevated concentrations of oligo-saccharides or maltose or maltotriose (Figure 3C)
the deviation depicted in Figure 3C originates from the addition of rice syrup
using a highly automated NMR approach in combination with a carefully assembled centralised database of authentic as well as known adulterated samples it is possible by means of ISO 17025 accredited untargeted methods to establish quantitative molecular fingerprints characteristic for natural honeys from different varieties and different origins
An important advantage of this approach is the fact that even yet unknown adulterations can be detected by untargeted uni- or multivariate tests
as NMR is quantitative for all signals detected above a threshold intensity
it also permits a targeted approach with a multitude of parameters simultaneously
Since NMR covers the analytical statements of several methods conventionally used in quality and authenticity testing of honey it can contribute to saving time and costs as well as producing so far unavailable information on authenticity and adulteration
Bremen) for many insightful discussions and Britta Zimmermann (ALNuMed) for expert technical help
Council Directive 2001/110/EC of 20 December 2001
http://en.wikipedia.org/wiki/Varroa_destructor
(2010) The German bee monitoring project: a long term study to understand periodically high winter losses of honey bee colonies
(2012) Effects of neonicotinoid dust from maize seed-dressing on honey bees
http://www.foodsafetynews.com/2013/02/honeygate-sting-leads-to-charges-for-ille-gal-chinese-honey-importation/#.U-H6lVY4ywc
(2008) Improved detection of honey adulteration by measuring differences between 13C/12C stable carbon isotope ratios of protein and sugar compounds with a combination of elemental analyzer — isotope ratio mass spectrometry and liquid chromatography — isotope ratio mass spectrometry (δ13C-EA/LC-IRMS)
(2009) NMR-based multi parametric quality control of fruit juices: SGF profiling
(2013) Targeted and nontargeted wine analysis by (1)h NMR spectroscopy combined with multivariate statistical analysis
Differentiation of important parameters: grape variety
Stephan Schwarzinger studied technical chemistry in combination with business administration at the University of Linz
This was followed by a period of post-doc work at The Scripps Research Institute
before joining the Department of Biopolymers at the University of Bayreuth in 2000
where he completed his habilitation in 2006 in biophysical chemistry
he served as interim head of the Department of Biochemistry at the University of Bayreuth
A member of the BIOmac research centre since 2010
he has been adjunct professor there since 2013
His research interests include NMR methods for the characterisation of flexible proteins
and the application of combined analysis methods
Bernd Kämpf studied food chemistry at the FH Isny
Since 1999 he is head of the laboratory and head of quality assurance at Breitsamer and Ulrich
2014 he was appointed executive manager at FoodQS
His interests lie in the field of honey analytics
Felix Brauer completed his graduate studies in biochemistry and a master’s in biochemistry and molecular biochemistry at the University of Bayreuth
He has worked as a research assistant at ALNuMed GmbH and doctorand at RC BIOmac since 2013
His research interests include NMR-based food analytics and the integration of methods used in metabonomics and spectroscopic profiling
Paul Rösch studied physics at the universities of Karlsruhe and Heidelberg before receiving his doctorate at the Max Planck Institute for Medical Research in Heidelberg
This was followed by a post-doc at the University of Pennsylvania Medical School in the USA
and a post as research assistant at the Max Planck Institute for Medical Research in Heidelberg
he completed his habilitation in biophysics at the University of Heidelberg
He has been head of the Department of Biopolymers since 1990 and Executive Director of the Research Centre for Bio-Macromolecules (RC BIOmac) at the University of Bayreuth since 2007
His key areas of research are NMR-based biomedical structural research
focusing in particular on the molecular basis of food allergies
and research into bacterial transcription as a target for new antibiotics
Issue 6 2015
Food Fraud, Nuclear Magnetic Resonance (NMR)
All subscriptions include online membership
giving you access to the journal and exclusive content
By Perten a PerkinElmer company
By Dr Timothy Wilks, Evangelia Zavitsanou, Prof Saskia Van Ruth, Selvarani Elahi MBE
By Professor Chris Elliott
By Ian Westcott
Thank for this technogy we are interested to send our Raw Black and green honey for NMR Honey profiling
I am a Scientist and setting up Quality Assurance Lab for Honey Testing in India for export purposes
This new innovation seems to be more reliable than LC-EA-IRMS
I have got few samples analyzed from Intertek
may i know terms and conditions including financial aspects
Comment * document.getElementById("comment").setAttribute( "id"
"a21162013566d5f6766ea417beb17f02" );document.getElementById("de5d8d4fb7").setAttribute( "id"
Write for us | Advertise with us
New Food is published by: Russell Publishing Ltd.Court LodgeHogtrough HillBrasted
© Russell Publishing Limited, 2010-2025. All rights reserved. Terms & Conditions | Privacy Policy | Cookie Policy
Website design and development by e-Motive Media Limited
Necessary cookies are absolutely essential for the website to function properly
This category only includes cookies that ensures basic functionalities and security features of the website
These cookies do not store any personal information
CookieDescriptioncookielawinfo-checkbox-advertising-targetingThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Advertising & Targeting".cookielawinfo-checkbox-analyticsThis cookie is set by GDPR Cookie Consent WordPress Plugin
The cookie is used to remember the user consent for the cookies under the category "Analytics".cookielawinfo-checkbox-necessaryThis cookie is set by GDPR Cookie Consent plugin
The cookie is used to store the user consent for the cookies in the category "Necessary".cookielawinfo-checkbox-performanceThis cookie is set by GDPR Cookie Consent WordPress Plugin
The cookie is used to remember the user consent for the cookies under the category "Performance".PHPSESSIDThis cookie is native to PHP applications
The cookie is used to store and identify a users' unique session ID for the purpose of managing user session on the website
The cookie is a session cookies and is deleted when all the browser windows are closed.viewed_cookie_policyThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies
It does not store any personal data.zmember_loggedThis session cookie is served by our membership/subscription system and controls whether you are able to see content which is only available to logged in users.