I chose a lilac tree to sit under while writing this article. The scent of lilac is completely exquisite, delicate, and evocative, and I wanted to use the perfume of the flower to create a memory trigger. At a very young age, I was seduced by the power of scent and taste. At age five, I would crush lavender seeds into water and, while sipping this delicately flavored beverage, would rub the oil onto my wrists. Now whenever I smell lavender, I feel calm and tranquil.
There is no doubt that scent elicits a powerful emotional response. Many of us are reminded of people in our lives or occasions from the past whenever we smell a particular fragrance. But as intriguing as scent is, taste is even more emotionally evocative and transportive, as it engages more of our senses. A delicious meal or even a piece of chocolate melting tantalizingly on the tongue can often be accompanied by exclamations of pleasure. Chefs and flavorists have the opportunity to use the senses to transport us somewhere magical.
The Science of Taste
Taste is a cumulative experience of what we see with our eyes, taste with our tongue, and smell with our nose. Visual cues set an expectation of delight or trepidation. Five basic taste receptors on our tongues detect sweet, salt, acid, bitter, and umami. More-complex taste sensations include the effects of heat, cooling, and carbonation. These are detected by the trigeminal system, or “free nerve endings,” in the mouth and nose. Finally, aroma is the characterizing part of taste and is created by a complex mix of many odor molecules.
There are some fascinating facts about the way we recognize aroma. Our brains are able to process thousands of odor molecules simultaneously and recognize the mix as one whole particular scent. The mechanism for identifying the molecules is not fully understood. Each of the odor molecules in the mix binds to a specific chemoreceptor in the olfactory epithelium—a group of cells on the surface of the nasal cavity. There are many theories to explain the bonding between odorant and receptor—from Amoore’s (1963) theory of molecular structure to Turins’ (1996) theory of molecular vibration. A simple explanation is that an excitation of the neuron occurs and triggers an electric charge to travel to the olfactory bulb. The olfactory bulb then transmits a signal to the brain’s limbic system, and the signal is interpreted by our natural database of odors based on past experiences.
A flavorist learns to reverse this magical process of the brain and breaks an aroma down into its individual constituents. Among these, there may be one component that is responsible for the character of the flavor. In herbs and spices, the characteristic aroma is commonly due to a single major component. For example, eugenol, whose odor is classified as spice, clove (see Wright, 2004, for discussion of the odor classification system used for flavor components) can be isolated from clove oil. Its odor is clearly recognizable as clove. Another example is vanillin (vanilla) in vanilla beans, a single recognizable chemical.
For the majority of food products, however, the aroma is an intricate mixture of components whose odors are quite uncharacteristic of the overall flavor. Alpha-ionone (floral, violet) is a key component of raspberry aroma but smells of violets. An analogy to flavor creation is a food product like mayonnaise. Mayonnaise is made from oil, vinegar, and egg. None of these ingredients have the characteristic flavor of mayonnaise, but when blended together in the correct quantity they transform into something we recognize.
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Connecting Emotion and Taste
Why do odors evoke an emotion or bring back past memories? Our odor memory is the first sense, at birth,to be activated. The limbic system, where olfactory pathways lead, is also responsible for controlling emotion and storing memories. The convergence of these neural activities explains why smell will often trigger a particular memory or a strong emotion.
At birth, the brain contains 100 billion nerve cells, or neurons, and this number decreases as we age. To start functioning, the neurons form interconnections. Each neuron can connect to 10,000 other neurons (Shatz, 1992). The strongest and fastest connections are made within the first six years of life and thereafter up to the age of 10. A child who grows up exposed to a rich sensory environment of tastes, smells, textures, and sounds will form a dense architecture. This is why learning a language or a musical instrument is easier during this part of our life.
Throughout life, we file positive and happy memories associated with smell, but this is much more apparent in early childhood. The emotional impact of experiencing a scent that connects us to early childhood is extremely evocative and intense.
Holiday foods are often aromatic, and the interconnections formed in the brain from the taste experiences are strong. Holiday flavors are a way in which we can connect the past with the present. Aroma memories of security and well-being experienced as a child are triggered. We particularly remember the good days from our childhood and obscure the bad days. Holidays tend to be a happy time, which explains why we become emotionally attached to certain foods and flavors. Our studies have revealed that food aromas evoke memories of events, while fragrance tends to trigger memories based on personal relationships.
Mapping Emotional Response
The Sense of Smell Institute looked at the connections between odor and psychology and developed aromachology, the science of studying and measuring behavioral responses to aromas. Aromas activate the olfactory pathways that lead to the limbic system, the primitive part of the brain associated with the emission of neurotransmitters. Neurotransmitters such as endorphins, which can inhibit pain, and serotonin, which produces a relaxing effect, affect the brain and influence our mental and emotional state.
Aromachology is quite different from aromatherapy. In the latter, an aroma produces a therapeutic or healing response to the body. It is interesting to imagine that the brain’s interpretation of aroma may be able to trigger a chemical reaction resulting in an emotional response of our mind and body. Although a relatively new science, aromachology has had a significant impact on the development of fragrance products.
International Flavors & Fragrances (IFF) has developed a global database devised by Stephen Warrenburg, called ScentEmotions®, that provides emotional response data on flavor and fragrance materials. The Mood Mapping™ technique developed by him was used to collate positive and negative responses on more than 1,500 materials in many regions of the globe. The system documents the emotional, rather than strictly hedonic, responses to specific fragrances. The result is a database from which perfumers can draw informed inspiration.
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Eight major categories of mood adjectives are used in Mood Mapping, four positive (happiness, sensuality, relaxation, and stimulation) and four negative (irritation, stress, depression, and apathy). Each fragrance is evaluated by 80 or more panelists, who choose the best-fitting mood from the eight categories. This “voting” method allows panelists to focus their attention on these major categories of emotion, providing clearer differentiation among fragrances than “grading” methods where each mood is rated on a scale.
The database has been a valuable tool in our development of flavors. Understanding the emotional impact of aroma materials enables the flavorist to develop flavors that have the power to unleash emotions and memories through brain interpretation.
Crème orange fleur, from IFF’s Fine Flavors collection, is a unique blend of magical floral accords, together with the deep balance of cream. It sends even the most hardened of us into a trance as the ingredients penetrate the limbic system. The flavor has orange flower (Citrus aurantium) as a key ingredient. The perfume of this material is pleasurable and evokes happiness and relaxation.
Marrying Sight with Taste
IFF collaborated with Visionaire, a marketing and publishing company, to create Visionaire 47 Taste, an art book launched to the public at the Art Basel Miami Beach art show and exhibit last December. The creative talents of contemporary artists, chefs, athletes, and photographers were paired with IFF’s flavorists and perfumers to create works of art that stretched the sensual boundaries of imagination by marrying the senses of sight with taste. Mood mapping was used for some of the fragrance ingredients. People attending the event viewed the art work and tasted the flavor that evoked the emotions portrayed in the art work.
Twelve images representing various concepts were accompanied by specially made tastes to expand the sensory experience. Some of the tastes were traditional, some literal, and some completely abstract. Among the contributors were chefs Ferran Adría and Heston Blumenthal.
The flavors were delivered on taste strips similar to breath-freshener films (see sidebar “Flavoring Edible Films”). It was important that the chosen delivery system could not be spit out—the viewer had to experience the taste whether it was liked or not. The edible films fit this criterion nicely. They dissolve in the mouth very quickly, enabling one to move from one taste to the next in a fairly short length of time. They also have very few other active ingredients that interfere with the delivery and hence the experience.
Among the 12 concepts were the following:
• Luxury (image by Solve Sundsbo) is the taste of a pine cone tip, rarer than white truffle and more exquisite than caviar, that evokes the concept of “luxury” because the taste is so different, refined, and rare. The key to the luxurious fresh pine cone tips is the ripeness of the pines (Pinus Pinea). Only available in May and June, the fresh tips are picked from the trees around El Bulli Restaurant in Roses, Spain. A combination of pine needle, nutty, fatty, and fresh notes gives a sophisticated feeling in the mouth.
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• Exotic (image by Nobuyoshi Araki) is a blend of mangos, orange blossom, and hot pepper. The painting of an exotic flower sets up an expectation of rarity and uniqueness. The flavor is completely balanced and transports one into a dream of a place and time spent somewhere exotic and beautiful. As we taste Exotic, we feel the flesh of the fruit, smell the scent of the flowers, and soon find ourselves transported to somewhere extravagant and beautiful. We begin to feel the warmth of the sun and then realize that it is the heat from the pepper. This is another example of utilizing the flavor of orange flower to evoke happiness and pleasure.
• Orgasm (image by Vik Muniz) is a seductive mélange of chocolate, black truffle, honey, vanilla, musk, sweat, and other body secretions that penetrates the senses and marries well with the amazing image created using chocolate as the paint. The musk note is used in a number of different flavors to provoke relaxation and emotional attributes of sensuous/sexy and relaxing. The major components of the musk note are ambrettolide (musk, berry), cis-5-tetradecen-1,14-olide (musk), and farnsyl acetate (floral, lily).
• Guilty (image by Richard Phillips) combines luxury and indulgence, using creamy milk chocolate with an undertone of leather, evoking “sinful.”
The overwhelming response to Visionaire 47 Taste has convinced us further of the value of exploring the emotional aspects of flavor. Understanding flavor chemistry and knowing how materials evoke responses creates unbelievable taste experiences. The future looks exciting as the emotional element of taste becomes valued. The time is right in the marketplace, as there is a big drive to develop new products for health and wellness.
In the future, we will see more new products that not only benefit health but also provide tastes that enhance our mental well-being.
In the late 1970s, the Japanese introduced a novelty product called Leaves of Freshness, a film product similar in shape to the breath-freshener products in today’s marketplace. The products were citrus-flavored with strong floral notes and were used as breath-fresheners.
The primary ingredient in the manufacture of edible films and capsules is the carrier. Three major carrier systems are used—starch, proteins, and polysaccharides. Many companies use combinations of carriers to obtain their desired tensile strength and dissolution properties. Taste-film systems in North America utilize pullulan, sodium alginate, and hydroxypropyl methylcellulose, alone or in combination.
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The basic steps in manufacturing the film strips are as follows:
Ingredients, consisting of, but not limited to, water, food-grade polymers (e.g., hydroxypropyl methylcellulose, alginates), starches, sweeteners (acesulfame-K, aspartame, saccharin), surfactant (polysorbate 80), plasticizer (glycerin), color, and flavor, are added to a jacketed tank, blended, and emulsified into a consistent slurry.
The emulsion slurry is fed slowly to a holding pan at the beginning of a production belt. The slurry is fed thru sizing bars (rollers), designed to control the thickness, onto a slowly moving belt, typically of Mylar, approximately 3 ft wide by 100 ft long (width and length can vary with different manufacturers). The slurry travels at a controlled speed through various stages of drying, which may include steam, hot air, or a combination of both. At the final stage of the belt, the dried film is exposed to cool air to help it cool down before being released and wound onto spools. After analysis and clearance, the spools are cut and packaged.
In 2001, Warner-Lambert Co. (now owned by Pfizer Inc.) introduced the first edible film in the marketplace and revolutionized the delivery of flavor and active ingredients. The product, Listerine PocketPaks, experienced phenomenal growth, with sales of $160 million in 2002. With a product so successful, other companies quickly followed suit. Kraft Nabisco quickly introduced Altoid films, and Wrigley introduced films bearing the names of Extra and Eclipse, two of the company’s extremely popular and successful chewing gum brands.
Although the oral-care-film market has peaked and the confectionery-film market has dropped to a very small fraction of what it once was, the market with the most potential for growth is for films delivering functional ingredients, such as vitamins, supplements, and drugs.
by John Sondrup, Manager of Confectionery Applications, International Flavors & Fragrances Inc., 521 W. 57th St., New York, NY 10019.
Amoore, J. 1963. Stereochemical theory of olfaction. Nature 198: 283-284. Shatz, C 1992. The developing brain. Scientific American 267(3): 60-67.
Turin, L. 1996. A spectroscopic mechanism for primary olfactory reception. Chem. Senses 21: 6773-6791
Wright, J. 2004. Sensory subjects. Chpt. 5 in “Flavor Creation,” p. 196. Allured Publishing, Carol Stream, Ill.