Food Chemistry Advances (Oct 2022)
C4 sugar adulteration methodology: Understanding false-positive results for mānuka honey
Abstract
Mānuka honey produced in New Zealand by Leptospermum scoparium is a highly sought product around the world due to the presence of methylglyoxal (MGO). Exported honey is required to undergo a number of authenticity and quality tests to provide evidence that the batch of honey has passed certain market requirements. Assurance that honey has not been adulterated with sugar of C4 origin (e.g. high fructose corn syrup) is carried out by the internationally recognised AOAC 998.12 C4 sugar adulteration test. In the past decade there have been concerns around the testing of mānuka honey using this method due to honey with a high concentration of methylglyoxal (MGO, >250 mg/kg) often failing the test. It has been considered that a negative shift in δ13Cprotein causes false-positive fails due to a limitation in methodology. A review of the literature has been carried out to determine possible causes for this failure and identifies more suitable methods of analysis.
