Food would be boring without spices. They give aroma, color, flavor, and sometimes even texture to food. Each spice, chile, or herb has specific, unique chemical compounds that create the sensual qualities for which we value them. Aroma is inextricably intertwined with taste and flavor—which are often considered interchangeable terms, though here they are not—in the discussion of spice profiles. Taste, for the purposes of this discussion, revolves around the five flavors our tongues have receptors to identify: bitter, salty, sour, sweet, and umami. Flavor is the reaction that occurs when our tongue processes food via the taste receptors on the tongue in combination with the input from aroma.
According to food scientist Dr. Guy Crosby, humans are able to identify approximately 10,000 individual odors. There are receptors for smells in the nose, of course, but we also have smell receptors along the back of the mouth and into the sinuses; the fusion of information from physical taste and orthonasal (nose) and retronasal (sinus) receptors create the overall sense of flavor. This allows our palate to expand beyond the flavors physically detected by the tastebuds on our tongues.
Spices can exhibit essences of the five basic flavors of bitter, salty, sour, sweet, and umami. We’ve gone a step further and defined twelve other groups of flavors that feature prominently in our food repertoire. These 17 flavor and taste characteristics can combine in, literally, tens of thousands of ways. Thanks to the manner in which our senses work together to interpret our world we can enjoy spices with complex flavor profiles that can be simultaneously cooling, earthy, floral, fruity, herbaceous, hot, nutty, piney, pungent, spicy, sulfury, or woody.
The Sensory Characteristics of Spices - The Five Basic Tastes
Often described as pungent, acrid, or sharp, “bitter” is one of the five tastes for which we have receptors on our tongues. Food historians tend to believe that we developed the inherent ability to determine bitter tastes in self-defense—toxic compounds tend to give off bitter flavors, so tasting them would signal us to spit that food out. But not all bitter foods are toxic; when used judiciously in food preparation, a bitter element can bring balance to sweet food, enhance umami, and cleanse the palate by cutting through rich flavors, which then allows us to enjoy our food without being overwhelmed.
Bitter flavors can be found in a wide range of herbs and spices, and some of them may surprise you. Examples of bitter flavors include Ajwain Seeds, Bay Leaves, Black Cumin Seed, Celery Seed, Fenugreek Seeds, Greek Oregano, Horseradish Root Powder, Lavender, Mace, Marjoram Leaf, Mediterranean Thyme, Mustard, Turmeric.
We all know the brackish, prickly taste of salt, that serves to make other flavors pop. It is the only rock we eat, and it comes in a wide range of colors and sizes, from snowy white and finely ground to black and coarse. Color usually indicates the presence of external minerals, like the clay or rock from which it’s been harvested. Unless a flavor, like smoke, has been added to a salt, the difference in color doesn’t mean a difference in flavor. The most telling difference in salt relies on its structure; fine grinds dissolve easier and taste more “salty”, while coarser salts taste longer and disperse their flavor over a greater period of time.
Sour tastes, that pinch the sinuses and pucker the mouth, indicate the presence of organic acids. One of the five basic tastes, sourness serves as a warning that food might have gone bad or be harmful. Acidic tartness, when applied sensibly, can bring playful balance to food; think of how a squeeze of lime brightens up the heaviness of a beef enchilada.
Our tongues are wired to taste sugary sweetness. At its most basic form, sugar is energy, and our taste buds want sweetness because we want to find simple ways to ingest that energy. Sugar binds with chemical receptors in the mouth and goes directly to the gustatory cortex—the part of the brain that processes flavor and taste—triggering pleasant sensations and perceptions.
Some sweet spices include Allspice, Anise, Caraway, Cassia Cinnamon, Chervil, Cloves, Dill Seed, Fennel, Green Cardamom, Nutmeg, Poppy Seed, Sesame Seed, Star Anise, Granulated Honey, Granulated Molasses
Umami – The newest taste to be officially recognized, umami is generally described as the savory and deep quality that gives craveable richness to foods. It was originally linked to the presence of glutamic acid found in seaweed, but has also been connected to the compounds inosinate and guanylate, which are often present in high-protein food.
The Sensory Characteristics of Spices - The Supporting Flavors
Cooling flavors don’t actually drop the temperature in your mouth. The cool sensation you get from herbs like mint is known as chemesthesis, a reaction that occurs when certain chemical compounds in food activate certain receptors in your mouth. The protein TRPM8, which responds to the presence of menthol, tricks your mouth into feeling cool, even though a thermometer wouldn’t register a physical change.
Earthy flavors are rich and minerally. They originate from an organic compound called geosmin, that is present in soil and can impact the foods that grow closely in it, like potatoes and beets. We are particularly sensitive to the presence of geosmin, and are able to detect it at concentrations of 400 parts per trillion.
Floral flavors tend to be sophisticated and elegant, and surprisingly strong. They can be tart, or bitter, or peppery, but share aromatic qualities that trigger the smell receptors that line the nose and throat. Their smell is a profound factor in their flavor and we are wired to detect florals—we smell one of the chemical compounds in the aroma of roses at concentrations of 5 parts per billion—so they are easy to over-use. Used wisely, they bring ethereal fragrance and gentle sumptuousness to food.
Fruity – Fruity flavors are generally bright and bracing. They can be juicy and berry-like, or tart and citrusy. Fruit flavors are often the result of the presence of esters, a compound that develops from the synthesis of organic alcohols and acids.
Herbaceous – Herbaceous flavors are full of personality. They don’t rely on one particular chemical compound for definition but rather, express the overall presence of an herb. The flavors can range from clean and grassy, like parsley, or warm and peppery, like sage, with a welcoming perfume that lingers as the flavor fades.
Hot spices work the same way that cooling spices do, triggering a reflex reaction—chemesthesis—rather than changing the physical temperature of your mouth. The chemical that causes the change is, most often, capsaicin, the active heat compound in chile peppers that gives it that fire, though there can be other compounds that elicit similar reactions. Piperine, in black pepper, is what gives that spice its signature bite.
When a food tastes nutty—rich, a little fatty, with a savory woodsiness that’s perhaps even a little buttery—it indicates high concentrations of Strecker aldehydes, a compound that develops as amino acids degrade. This flavor is often found in high-fat, high-protein seeds.
The aromatic, biting, balsamic pine flavor that can be found in various herbs and spices is the result of a volatile organic compound called—perhaps unsurprisingly—pinene. This compound is found in a wide variety of plants, which are not necessarily related to pine trees. It easily aerosolizes, which means that plants that express pinene have a rich fragrance.
Pungency is not the cause of one specific volatile compound but rather, a way to describe boldly flavored spices and herbs. It’s not particularly hot, acrid, sharp, or biting, though it can be any or all of these. Pungent flavor providers, like garlic, tend to keep delivering the pungent flavor through the course of a meal and, sometimes, beyond that.
Spicy foods are piquant and bold. They are often hot but are most notable for delivering a flavorful, one-two punch that’s dominated by the zingy way it lifts the palate. Spicy flavors tend to mellow fairly quickly into a gentler finish on the tongue.
Some of the world’s most beloved ingredients, like onion and garlic, get their distinctively sharp and aggressively aromatic flavor profiles from the presence of sulfur compounds. On its own, sulfur can smell off-putting and almost egg-y, but when these compounds are treated with heat they become savory and alluring. Sulfur is an essential mineral for the human body, as it plays roles in DNA repair, cell protection, and the metabolization of food.
Woody flavors are not beholden to one particular chemical compound. Instead, they evoke the idea of a damp, fragrant wood, like mellow cedar. They are often robust and warm, with a sprinkling of piquancy.
While there are only five “tastes” that our tongues process independently, thanks to the interplay between nose, tongue, throat, and brain, we can perceive many, many more flavors. Some rely on chemical compounds to distinguish them, while others are defined by their aroma. At the personal level, flavor can trigger memories, creating another way to perceive herbs and spices and define one’s personal palate. But the best way to understand the flavors discussed above, is to simply try them. Get ready to dig in and expand your perceptions of food and flavor!
Hungry for more information?