Spice Flavor and Aroma Guide: Sweet, Hot, Earthy, Smoky, Citrusy and More

Taste and aroma are two different things

Your tongue picks up only a few basic tastes: sweet, salty, sour, bitter and savory (umami). [1] Everything else you notice when you eat, such as telling an apple from a pear, comes from smell. [1]

While you chew, tiny aroma molecules travel from your mouth up the back of your nose to the smell receptors. This is called retronasal smell. It is different from sniffing, which brings smells in through the front of the nose. [1] Your brain blends the two signals into what we call flavor. [1] That is why food tastes flat when you have a blocked nose. [1]

Spices are mostly an aroma story. A teaspoon of cumin adds almost no taste on the tongue, but it adds a lot of smell. Only a few spices add a real basic taste, such as the bitterness of fenugreek.

Heat is a third thing

The burn of chili and the bite of pepper are not tastes. Capsaicin, the compound in chilies, switches on a receptor called TRPV1 on pain-sensing nerves, and the brain reads this as burning even though nothing is actually hotter. [2] Piperine, the compound in black pepper, switches on the same receptor. [3] The sources we read describe this as a nerve sensation, not a taste.

Some other "hot" spices work differently. Horseradish and wasabi release their sharp compound only when cut or grated, and wasabi is felt more in the nose than on the tongue. Our horseradish and wasabi page explains why that heat fades quickly.

The ten flavor labels on this site

Each spice page lists up to four labels, with the strongest first. The labels come from the flavor notes written for each spice page, which are sourced there. The list below includes only spices whose finished page carries that label.

The "smoky" label is kept for spices where smoke is part of the character, such as smoked paprika. Plain paprika says only that smoked types smell of wood smoke.

Sweet spices: taste or smell?

Many "sweet" spices are sweet mostly in the nose. Cooks often call cinnamon, cloves, vanilla and star anise sweet, yet the sources we read do not describe any of them as containing sugar.

Research helps explain this. In a Penn State study, blind tasters rated milk with vanilla aroma as sweeter than its sugar level would predict. The researchers link this to a learned bond between the smell of vanilla and sweetness. [4] A separate lab study found that some food odors can raise how sweet a sugar solution seems, even at levels too faint to notice. [5]

So a spice that smells sweet can make a dish seem sweeter without adding sugar. That is useful in baking, and it is why vanilla and cinnamon feel at home in desserts.

What we could not confirm: we found no source that measures whether cinnamon, cloves or star anise taste sweet on their own tongue, apart from their smell. Our vanilla page says the bean tastes sweet and creamy, but the Wikipedia vanilla article we read does not describe its taste or say it contains sugar. [6] Treat "sweet" on this site as how the spice seems when you smell and taste it together. Star anise gets its licorice note from anethole, the same compound as in anise. [7]

Why heat, toasting and grinding change flavor

The aroma compounds in spices are volatile, which means they escape into the air. They fade in pre-ground spices before the jar is opened. Toasting and grinding whole spices just before cooking releases them while they are fresh. [8] Toasting also adds new flavors through browning of the spice's proteins and sugars. [8]

Here are examples from our spice pages. Each has its own sources.

• Cumin smells deeper and nuttier after toasting, because toasting forms new aroma compounds called pyrazines.
• Fenugreek loses some bitterness when the seeds are roasted whole before grinding.
• Asafoetida smells harsh in the jar and turns mellow when cooked in hot oil.
• Sichuan pepper loses its tingle with long cooking, so many cooks add it near the end.
• Horseradish and wasabi lose their bite when exposed to air and heat.
• Cloves give up their flavor faster when ground than when whole.

Different spices react differently. Heat can deepen one spice and ruin another. Check the page for the spice you are using.

Pairing flavors in practice

Think of a dish as having a few jobs: something warm, something bright, something with bite, something earthy. A curry might use turmeric and cumin for earth, ginger for brightness and heat, and cinnamon for warmth. This is a cooking idea, not a research finding.