Manuka may not be the bee’s knees after all, research shows

Consumers may want to think twice before paying a premium for manuka and other monofloral honeys. Research from New Zealand’s Lincoln University has shown that a number of honeys from NZ are not true to label.

Lincoln University PhD candidate Patchanee Boontaganon undertook a comprehensive physical and chemical analysis of 74 NZ honeys and found that 29 out of 64 monofloral honey samples from supermarkets were not true to label, based on pollen count.

Boontaganon used standard industry analytical methods to confirm the floral identity and nutritional contents of the honey. Analytical methods were used to quantify hydrogen peroxide content and antioxidant activity in the honey.

Hydrogen peroxide occurs naturally in honey and plays a major role in its antimicrobial activity while antioxidants protect against free radical damage.

Boontaganon found that the majority of the honeys had similar results, except for manuka honey and manuka honey blends, which had much higher antioxidant and hydrogen peroxide levels and was a darker colour than clover honey.

The New Zealand Guidelines for Mono-floral Varieties of Honey produced by the Bee Products Standards Council contain the minimum percentage of pollen needed from a specific plant before a honey can be marketed as a named (monofloral) honey. In this study, fewer than half the manuka honeys were true to label.

The Lincoln study and other research has shown that manuka honey contains high levels of several beneficial compounds, so consumers are willing to pay extra for these properties.

“However, in view of my results, it is essential that the honey industry invests funds into ensuring all honey is true to label to maintain consumer confidence in this delicious food,” said Boontaganon.

“Readers may be aware of publicity around another issue in the honey industry in regard to incorrect UMF (unique manuka factor) levels being put on manuka honey labels,” said Associate Professor Geoffrey Savage, who was Boontaganon’s supervisor. “While this is unrelated to Patchanee’s research, it highlights the importance of the honey industry, ensuring the integrity in the identification of all honey - not only highly prized varieties like manuka.”

Boontaganon presented the results of her research at the NZ Nutrition Society conference in Queenstown.