Exploring the Characteristics of an Aroma-Blending Mixture by Investigating the Network of Shared Odors and the Molecular Features of Their Related Odorants

Abstract

<jats:p>The perception of aroma mixtures is based on interactions beginning at the peripheral olfactory system, but the process remains poorly understood. The perception of a mixture of ethyl isobutyrate (Et-iB, strawberry-like odor) and ethyl maltol (Et-M, caramel-like odor) was investigated previously in both human and animal studies. In those studies, the binary mixture of Et-iB and Et-M was found to be configurally processed. In humans, the mixture was judged as more typical of a pineapple odor, similar to allyl hexanoate (Al-H, pineapple-like odor), than the odors of the individual components. To explore the key features of this aroma blend, we developed an in silico approach based on molecules having at least one of the odors—strawberry, caramel or pineapple. A dataset of 293 molecules and their related odors was built. We applied the notion of a “social network” to describe the network of the odors. Additionally, we explored the structural properties of the molecules in this dataset. The network of the odors revealed peculiar links between odors, while the structural study emphasized key characteristics of the molecules. The association between “strawberry” and “caramel” notes, as well as the structural diversity of the “strawberry” molecules, were notable. Such elements would be key to identifying potential odors/odorants to form aroma blends.</jats:p>

Why does that molecule smell?

“…[2,12] There are certain relationships between molecular structure and scent that are well-documented. [2,8,[13][14][15] For instance, it is known that esters tend to have a fruity and floral scent while thiols often are described as having a rotten or alliaceous scent. [8,14] Even though both tert-amyl acetate and n-amyl acetate have the ester functional group and are very similar in structure, tert-amyl acetate has a camphoraceous scent while n-amyl acetate has a fruity scent.…”

Analysis of the Ability to Produce Pleasant Aromas on Sour Whey and Buttermilk By-Products by Mold Galactomyces geotrichum: Identification of Key Odorants

“…However, it should be noted that the overall aroma of a mixture of many compounds is not just the sum of the intensity of their individual aroma descriptors [ 5 , 46 ]. The sense of aroma is influenced by olfactory coding (still poorly understood) and olfactory perception, the understanding of which has been greatly improved in recent years [ 47 ]. It has been shown that, for as little as four compounds that create the aroma mixture, a loss of their individual aroma notes can be observed.…”

Aroma Profile Development in Beer Fermented with Azacca, Idaho-7, and Sultana Hops

“…Seven of the top ten analytes were shared across all three single-hopped beers, although they varied in abundance (β-myrcene, 2-methylbutyl 2-methylpropoanoate, ethyl octanoate, ethyl trans-4-decenoate, ethyl decanoate, β-caryophyllene, and α-humulene). According to published odor descriptions of these analytes, the ethyl esters create a fruity, pineapple, pear, and brandy aroma while the monoterpenes and sesquiterpenes add woody, spicy, herbal notes at specific perception thresholds [17][18][19][20]. The aroma of 2-methylbutyl 2-methyl propanoate has been described as 'earthy' [19].…”

“…and sesquiterpenes add woody, spicy, herbal notes at specific perception thresholds [17][18][19][20]. The aroma of 2-methylbutyl 2-methyl propanoate has been described as 'earthy' [19].…”