A promising approach: honey-profilingTM
Honey – a natural product, consumed since thousands of years. But meanwhile, but also the methods for adulteration in order to improve profit. At first sight, consumers are the ones to suffer, but by losing trust into the honey producing industry, this eventually could work out as a disaster for all parties. Existing analysis methods work, but are quite tedious as an analysis for each type of adulteration is mandatory. So what are the options? Well, a very promising and already successful one is honey analysis by means of NMR spectroscopy.
Honey analysis by NMR spectroscopy
NMR spectroscopy is a new approach used by Quality Services International (Germany, Bremen, part of a consortium also consisting of Bruker BioSpin GmbH and ALNuMed GmbH) which allows honey profiling on a base of over 4.000 mono- and polyfloral honey samples taken from more than 45 countries around the world. A standardized platform, the Bruker Ascend 400 FoodScreenerTM from Bruker BioSpin GmbH (Rheinstetten, Germany), is used to collect results and with every further sample, the database evolves. These several thousands of samples made it possible to develop a precise quantile plot for honey analysis which can be superposed by the test sample – potential changes from normality can be detected very quickly visually. Those changes which cannot be seen easily in the quantile plot will be detected by comprehensive statistical analysis. Not much time is needed for data acquisition. One measurement takes just 20 minutes.
Interested readers will learn more about NMR spectroscopy in our QSI blog – visit http://qsi-q3.de/en/news-information/nmr-analytics/
Honey-profilingTM: Bright future ahead
NMR spectroscopy is already a reliable method to confirm the authenticity of food, especially for wine and juice. No doubt that this analysis method also has a bright future ahead concerning honey: Established in 2014, honey-profilingTM already offers the quantification of 38 individual parameters – from glucose and fructose concentration up to several organic acids like lactic acid or formic acid.
Today, the results are already remarkable, but research shows that there is still potential for some further development. As the database grows with each sample, experts from QSI create an excellent basis for future extensions of the statistical examination of geographical origins as well as for refined detection patterns and markers. The expected result is to gain a lot more than 38 parameters in order to detect adulteration in honeys even more comprehensive. One example is Manuka honey: For proving authenticity in this special case, it is presently necessary to evaluate several substances and their ratios to each other, which is done manually. The concentration ratio between them reveals a very unique finger print which facilitates the detection of potential adulteration. Once enough data has been collected the evaluation of the different substances can be combined automatically yielding only one parameter (adulterated/authentic).
Distinguishing unripe from adulterated honey
Another field of research is the question whether a honey is ripe or not – and if so, if it is adulterated. This phenomenon occurs in some Asian countries, where honey normally gets centrifuged before bees start capping the honeycombs. They don’t get capped until the nectar reaches a certain reduced water content. Enzymatic reactions, triggered by the bees, also take place during this ripening process. Especially in China, an unripe harvest is quite usual and unripeness does not mean adulteration automatically. But some competitors may use a post-treatment for unripe honeys which are too watery – what, of course, is prohibited by the European “Council Directive 2001/110/EC” (Official Journal of the European Communities).
Now, preliminary results confirm that NMR spectroscopy allow conclusions about the ripeness of honey. Fermentation parameters (e. g. acetic acid, lactic acid) provide a basis in this case, to give just one example: Fermentation causes a significant increase of these substances in watery, unripe honey (>20 %) in comparison to ripe honey with a low water content (<20 %).
Feel free to read more about this topic in q&more, a German scientific magazine (edition 01 2016), written by experts from QSI and colleagues: http://q-more.chemie.de/q-more-artikel/234/authentische-lebensmittel.html
It is one aim to integrate these observations into statistical models for being able to differentiate between ripe and unripe honey and also between unripe and adulterated honey.
Preliminary tests showed that NMR spectroscopy also works with parameters like water content, acid value and conductivity, which are further aspects of honey regulation. Honey-profilingTM reached a remarkable level up to now, but with these improvements, it will get more sensitive, detailed and significant. May this new approach help to strengthen the consumer’s trust into honey? Very likely. It has never been more efficient to detect false declarations whereby NMR spectroscopy could become number one in honey analysis methods very soon.
Source Council Directive 2001/110/EC: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2002:010:0047:0052:EN:PDF