From yogurt to cookies and lattes, the vanilla flavor is highly sought-after by consumers. But, it’s one of the most labor-intensive crops, making it the second-most expensive spice in the world. Some manufacturers produce imitation vanilla in order to lessen the time-to-sale as well as cost; but, there is typically a significant difference in quality between the two.
Now, researchers at Ohio State University have used a relatively new, innovative method called “flavoromics” to identify 20 key chemicals found in vanilla bean extracts, including several previously unknown ones. The work could help manufacturers and farmers develop better-tasting vanilla and quicken the curing process, which currently takes about 9 months.
“Most of the studies have been focused on analysis of volatile compounds, basically the compounds associated with aroma perception,” explained lead researcher Diana Paola Forero-Arcila during her presentation at the American Chemical Society meeting. “Among them, vanillin has been recognized as the single most characteristic compound. However, the flavor is like a complex sensation, and it includes a lot of different interactions around aroma, the taste and other sensations you perceive when you are eating. Thus, [we need] a more holistic understanding of the molecules that are contributing to this complexity of the vanilla flavor.”
To capture the complexity of vanilla, Forero-Arcila used flavoromics to analyze a wide range of metabolites present in 15 different vanilla bean extracts sourced from various countries. Employing a myriad of analytical techniques, including gas chromatography (GC), liquid chromatography (LC) and tandem mass spectrometry (MS/MS), the team was able to construct a chemical profile of each type of bean and identify which compounds were present.
The researchers also asked more than 100 volunteers to taste the samples and rate whether they liked or disliked the flavors. Forero-Arcila and her team then modeled the chemical data with the sensory data obtained from the consumers to generate highly predictive models of like and dislike.
“We were able to identify the main drivers of vanilla flavor liking,” said Forero-Arcila. “Some of them are well known to be present in vanilla, but this is the first time we are actually reporting these compounds as influential for the vanilla flavor liking. We also identified some unknown compounds that are not only reported for the first time in vanilla, but are also highly predictive of vanilla liking and disliking.”
For example, the researchers identified anisaldehyde, which has a floral aroma, as an extract that causes most people to dislike the vanilla flavor. Anisaldehyde is produced during the curing process from a previously unknown precursor.
Forero-Arcila and her team are still analyzing all the novel vanilla compounds to determine the final structures, but principal investigator Devin Peterson says they will be able to demonstrate their findings on flavor and overall consumer behavior in a novel way.
“This knowledge will allow us to improve the ability to tailor the vanilla quality and also add value by innovating the generation of the specific compounds that we know are impacting the liking or disliking,” said Forero-Arcila. “This information will give the tools to the whole vanilla supply chain from farmers to industry.”
For example, in the future, vanilla breeding programs and curing methods could focus on selectively producing the optimum compound profile for desirable flavor in vanilla plants.