A New Methodology Based on GC−MS To Detect Honey Adulteration with Commercial Syrups

TLDR

Honey adulteration can be carried out by adding inexpensive sugar syrups such as high‑fructose corn syrup and inverted syrup. The authors used GC and GC‑MS to analyze carbohydrate composition of 20 honey samples and 6 syrups, employing an enrichment step to remove major sugars and preconcentrate difructose anhydrides, and developed a yeast‑based treatment that enables DFA detection in honeys with as little as 5 % adulterant. DFAs were identified for the first time in HFCS and IS, with concentrations varying by syrup type, and their absence in all honey samples indicates that DFAs can serve as a marker of adulteration, detectable by the yeast‑based GC‑MS method at concentrations as low as 5 % (w/w). Keywords: Adulteration; honey; syrup; difructose anhydrides (DFAs); yeast; GC‑MS.

Abstract

Honey adulterations can be carried out by addition of inexpensive sugar syrups, such as high fructose corn syrup (HFCS) and inverted syrup (IS). Carbohydrate composition of 20 honey samples (16 nectar and 4 honeydew honeys) and 6 syrups has been studied by GC and GC−MS in order to detect differences between both sample groups. The presence of difructose anhydrides (DFAs) in these syrups is described for the first time in this paper; their proportions were dependent on the syrup type considered. As these compounds were not detected in any of the 20 honey samples analyzed, their presence in honey is proposed as a marker of adulteration. Detection of honey adulteration with HFCS and IS requires a previous enrichment step to remove major sugars (monosaccharides) and to preconcentrate DFAs. A new methodology based on yeast (Saccharomyces cerevisiae) treatment has been developed to allow the detection of DFAs in adulterated honeys in concentrations as low as 5% (w/w). Keywords: Adulteration; honey; syrup; difructose anhydrides (DFAs); yeast; GC−MS.