How Aroma Affects Honey’s Sweetness

Honey has been used as a sweetener for thousands of years. Yet the mechanics of its sweetness have been a mystery.

There has been some research linking the sweetness of fruit with aroma compounds, says Emily Mayhew, assistant professor at Michigan State University’s Department of Food Science and Human Nutrition. “The sugars are obviously contributing to the sweetness of fruits, but also the aromas are playing a really big role,” she says.

She wondered whether the same would hold true for honey, and, if so, whether the sweetness-aroma combination could be exploited for healthier products. “If we can experience sweetness through a combination of sugars and aromas, then we can use those aromas to reduce the amount of sugar we need to still experience that pleasurable sweetness,” she says.

Research by Mayhew and her colleagues, recently published in the Journal of Food Science, aimed to answer two questions: How sweet is honey, and does aroma affect how sweet it tastes?

The research was supported by the National Honey Board because, surprisingly enough, they also didn’t know, and they were interested in data to support sugar substitutions, Mayhew explains.

“There was some conventional wisdom that honey was maybe sweeter than sugar, but it’s not clear in what units or what’s the appropriate substitution ratio to match the sweetness of sugar using honey,” she says.

Honey is mostly sugars (about 80%) and water, with a few minerals and vitamins. There are also more than 600 volatile organic compounds found in honeys, made up of flavonoids and phenolic acids. The aromas of honeys differ depending on the source of the nectar. Wildflower honey smells different than almond honey, for example.

“There are a lot of variables that can change the aromas that are present in honey,” Mayhew notes.

Aroma’s Role

The research she and her colleagues did incorporated both a tasting panel to see if there was a link between honey’s aroma and sweetness and chemical analysis to establish which volatile organic compounds might be responsible for sweetness.

Four honeys were used for the research—alfalfa, wildflower, orange, and clover, each of which was diluted with water. There was also a sugar-water mix control that used cane sugar. A panel of 55 tasters sampled each of the five mixtures twice, once with and once without nose clips.

For all the mixtures, the sweetness of sugar and honey was pretty much rated the same by the panel when sampled without the nose clips. But with the nose clips on, blocking the aromas, the tasters said the control sugar mixture was the sweetest.

“When people rated the sweetness intensity of the honey with their noses pinched, we saw that sweetness went down significantly,” says Mayhew. “What we found is that the aromas in honey are kind of bridging that gap.”

Because honey is about 80% sugar, subbing honey for sugar means a 20% lower sugar content. Yet because the honey’s smells are contributing to the sweet taste, the taste remains the same as if sugar was used. “Effectively, we’re getting 23% to 43% sweetness enhancement because of the aromas that are present in the honey,” says Mayhew.

The chemical analysis revealed that each of the honeys had 64 or more aroma compounds. Orange honey had the most, with 87 compounds, and clover the least, at 64 compounds. The researchers would like to know more about how specific compounds impact sweetness, by themselves and in blends.

They’re also doing follow-up work digging into the role of specific compounds and compound combinations in aroma and sweetness. They also want to look at the more complex interactions of ingredients and processes because the study used only isolated, water-based solutions. For example, aroma is affected by temperature, so heating up honey during processing would change the sweetness levels.

“I think there are some special considerations that a formulator should take, knowing that the aromas are fragile and the aromas are contributing a significant chunk of the sweetness,” says Mayhew.ft