Food fraud: Testing honey with NMR-profiling
9 December 2015 • Author(s): Stephan Schwarzinger, Felix Brauer and Paul Rösch, Research Center for Bio-Macromolecules, University Bayreuth, ALNuMed GmbH / Bernd Kämpf, FoodQS GmbH, Markt Erlbach
Rapid testing of variety, geographic origin, and absence of adulteration by NMR-profiling
Honey – for thousands of years it has been the only source of sweet taste, and it still is the prototype of an all-natural, healthy food. In particular with the growing trends for organic food and a healthy life-style honey has enjoyed steadily increasing popularity. Unfortunately, while demand is on the rise, supply is short. The reasons for this are complex and interwoven and have their origin in bee diseases, climate change as well as agro-industrial production methods. As a consequence, 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, olive oil or wine, 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. However, serious issues in honey production complement the rise in the demand for honey. A complex combination of factors, 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, pesticides, and insecticides, 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. In addition, the changing climate impacts honey production, as observed, e.g., in 2014, 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, e.g., corn, rice, or wheat at a fraction of the price of honey. Mixed products, 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, a type of fraud known as ‘honey laundry’. 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.
ABF Ingredients ANDEROL EUROPE BV Armfield Ltd Avantes Berndorf Band GmbH BIOTECON Diagnostics GmbH Cargo Oil AB Elea GmbH Engilico FUCHS LUBRITECH GmbH GLOBALG.A.P. Foodplus GmbH InS Services (UK) Ltd IONICON Analytik GmbH JAX INC. JBT Corporation LUBRIPLATE Lubricants Company NETZSCH Pumpen & Systeme GmbH NSF International Ocean Optics PCE Instruments UK Ltd R-Biopharm Rhone Ltd Randox Food Diagnostics Stancold SteriBeam The Tintometer® Group TOMRA Sorting Food Uhde High Pressure Technologies GmbH Verder UK Ltd Verner Wheelock Vikan UK Ltd