Understanding Drivers of Flavor Quality Using Flavoromics

May. 22, 2017

A core commitment of the Flavor Research and Education Center (FREC) is to support the advancement of the flavor quality of healthy food options. Flavor quality is considered one of the main product attributes that influences food choice. Healthier foods options are often inferior in flavor quality, which impedes consumption and thus health impact. Historically, flavor research has focused on improving flavor by reducing levels of specific undesirable flavors, or increasing levels of desirable attributes. The general scientific approach has been to define the flavor profile by a sensory panel, then attempt to identify the chemistry which drives those attributes. This methodology involves separating out the chemical constituents by chromatography and tasting or smelling them individually and in isolation to determine which compounds evoke the attributes of interest. While these methods are unquestionably effective at identifying sources of off-flavors, or for finding characteristic flavor compounds, they have limited ability to define sensory interactions or complexity. To advance our understanding of flavor perception, driven by many chemical factors, a holistic approach which considers the sum and the interplay of those factors and their relationship to the sensory attributes of interest is needed.

To accomplish this goal, the Flavor Center has developed an extension of untargeted metabolomics for studying small molecule flavor chemistry, termed flavoromics. In a flavoromics experiment, samples from different groups or expressing different levels of an effect of interest (e.g. fresh vs aged citrus extracts) are chemically profiled to obtain as much information as possible on their constituent chemistries. Chemical profiles from many different samples are analyzed using multivariate statistics or machine learning techniques to build models predictive of the effect of interest. By interrogating these models, we can determine compounds which are well correlated to the effect of interest, and thus can hypothesize that they may be chemical drivers of the sensory attribute(s). To test this hypothesis, we then isolate these compounds and recombine them back into the food system, to evaluate their impact on perception. For compounds which have flavor impact, formation pathways are elucidated in order to provide manufacturers with insight on how to modify ingredient selection, processing techniques, or breeding strategies in order to naturally produce better tasting products.

Geoff Dubrow, a PhD candidate in the Flavor Research and Center, is focused on further developing and applying flavoromics towards understanding the chemical drivers of flavor in fruit spreads, such as jams. Research to-date has focused on understanding how sugar reduction impacts product chemistry, and thus flavor quality. By profiling and modeling differences between fruit spreads of varied sugar content, novel flavor-modulating compounds have been identified which appear to lend a sensation of “fullness” or “rounded flavor” to sugar-free spreads when recombined at the levels which they are present in traditional spreads. Interestingly, many of these compounds are themselves flavorless when tasted in isolation, suggesting that traditional techniques would have been unsuccessful in identifying them and thus supporting the effectiveness of flavoromics in uncovering the drivers of perception. Through this research, FREC aims to help the food industry provide delicious low-sugar fruit spreads to consumers seeking to maintain their dietary goals while still enjoying the foods they love.