Can Mixing Strawberry and Caramel Aromas Create a Pineapple Note?

A strawberry-like aroma and a caramel-like aroma. If you mixed them, would the result smell like a sweet strawberry confection? With one particular combination, researchers have reported that the mixture smells more like pineapple than either ingredient smelled on its own.

The materials were not fruit or caramel themselves, but odorants with different characteristics. In a study published in 2012, Barkat and colleagues examined odors made from two or three components and showed that the pineapple quality of the mixtures depended on both the combination of components and the experience of the person smelling them.

When do we perceive an odor as a unified whole?

When we smell coffee, we generally recognize it as coffee rather than counting its many components one by one. Yet we may also pick out a burnt note or an off-odor within that overall smell. Both perceiving a unified odor and extracting individual characteristics are part of everyday olfaction.

The researchers wanted to know whether even two or three components could blend into a whole that smelled more like a particular odor than the individual ingredients did, and whether people trained to analyze odors would perceive the same effect.

Instead of asking participants to identify the ingredients, they therefore asked them to rate how closely the overall smell resembled pineapple. This allowed them to investigate the coherence of the mixture without directing too much attention toward searching for its components.

Combining two strawberry-like and caramel-like components

The two central odorants were ethyl isobutyrate and ethyl maltol. In this line of research, ethyl isobutyrate is treated as a fruity, strawberry-like odorant, and ethyl maltol as a caramel-like one.

The researchers mixed these two at specified concentrations and proportions, and also prepared a three-component mixture with allyl alpha-ionone added.

For comparison, they prepared another mixture using a different fruity component, ethyl caproate, and the caramel-like odorant furaneol. This made it possible to ask whether any fruity and caramel-like pairing would similarly enhance pineapple likeness.

The participants evaluated 10 samples in all: these three mixtures, the five individual ingredients, and two pineapple-like comparison samples.

For 20 untrained participants, the mixtures smelled more like pineapple

The first experiment involved 20 students without special training in olfaction or sensory evaluation. They smelled paper strips carrying the samples inside numbered test tubes.

They first ranked the 10 samples by how pineapple-like they smelled. The presentation order was then changed, and they rated each sample on a nine-point scale from not at all pineapple-like to extremely pineapple-like. Their reference was their own memory of pineapple odor, rather than a fruit placed in front of them.

Both the two-component mixture of ethyl isobutyrate and ethyl maltol and the three-component mixture containing allyl alpha-ionone were rated as more pineapple-like than their individual components. Ranking and numerical ratings pointed in the same direction.

In the two-component mixture, combining a strawberry-like fruity odor with a caramel-like odor increased the resemblance to a different fruit: pineapple. However, the mixtures scored only around 5–6 on the nine-point scale. The findings do not mean that they were indistinguishable from real pineapple.

Another fruity-plus-caramel combination did not produce the same effect

The combination of ethyl caproate and furaneol gave a different result. The mixture was more pineapple-like than furaneol alone, but less pineapple-like than ethyl caproate alone. Mixing the two did not produce a rating higher than both ingredients.

This comparison illustrates how difficult it is to predict a blend’s impression from odor labels alone. Even when the broad categories are the same, fruity and caramel-like, different molecules can change how the whole is perceived.

Another example of a difference between an odorant’s individual smell and its role in a mixture appears in Can Adding a Green Note to Vanilla Make It Smell Like Rum? That article examines different combinations, including vanilla odor and 3-octen-2-one.

People trained in wine evaluation rated individual components differently

The same samples were then evaluated by 32 oenology students learning wine tasting and the verbal description of aromas. They were not all professional perfumers: the relevant expertise here was in wine sensory evaluation.

In this group, there was no significant difference in pineapple likeness between the two- and three-component mixtures containing ethyl isobutyrate and ethyl isobutyrate alone. The untrained group’s finding that mixing produced a more pineapple-like odor than any individual ingredient was not reproduced here.

Importantly, this does not mean that the trained participants stopped perceiving the mixtures as pineapple-like. They too rated both mixtures at around 5–6. The substantial difference concerned ethyl isobutyrate on its own: the untrained group’s mean was 3.5, whereas the trained group’s was 5.0. The trained participants perceived greater pineapple likeness even in the single component.

The authors noted that ethyl isobutyrate is used as an example of a fruity aroma in wine training. Familiarity with it may have made the similarities between the individual component and the mixtures easier to recognize. The groups may also have held different mental reference points for pineapple odor.

However, the experiment did not compare the same people before and after training. It compared two groups with different prior experience, so training alone cannot be identified as the cause of the difference in ratings.

Can we say that an entirely new odor emerged?

In this study, the individual components already had some pineapple likeness, even if it was weak. The authors therefore discussed the result as incomplete blending: some component characteristics remained while the whole became more pineapple-like, rather than the ingredients’ characteristics disappearing completely and turning into a different odor.

An alternative explanation also remains possible: combining several pineapple-like features may simply have made the mixture seem more convincing. These evaluations did not directly identify where in the nose or brain the change occurred, or establish how well the ingredient odors could be recognized within the mixtures.

The samples were also tested at specified concentrations and proportions. The same findings do not necessarily apply to a dish made with strawberries and caramel, commercial strawberry and caramel flavorings, or formulations with different proportions.

Summary

When ethyl isobutyrate and ethyl maltol were mixed under the specified conditions, untrained participants rated the mixture as more pineapple-like than either component alone. The three-component mixture showed the same tendency, but a different fruity-plus-caramel pairing did not exceed both of its components.

Participants studying wine sensory evaluation, meanwhile, more readily perceived pineapple likeness in a single component, narrowing the difference from the mixtures. To understand how odors form a coherent whole, we need to consider not only what is mixed and in what proportions, but also which odors the person knows and what reference they use. This experiment, built around a familiar fruit, shows that a small number of components can change the overall impression, and that the change is not uniform across people.

References

Barkat, S., Le Berre, E., Coureaud, G., Sicard, G., & Thomas-Danguin, T. (2012). Perceptual Blending in Odor Mixtures Depends on the Nature of Odorants and Human Olfactory Expertise. Chemical Senses, 37(2), 159–166. DOI: 10.1093/chemse/bjr086 / Full original article.

For the strawberry-like and caramel-like descriptions of the odorants: Agence nationale de la recherche. MULTIMIX: A MULTIdisciplinary approach to decipher the first step of aroma MIXture perception. Project summary by the principal investigator (accessed October 12, 2026).