Almost every spice on your rack is a dried piece of a plant, and between them they cover nearly the whole thing: bark, seeds, fruits, flowers, underground stems and even hardened sap. The part a spice comes from explains why some spices only release their flavor when cracked or ground, why one is costly and another cheap, and why two jars with the same name can behave differently.
How Spices Differ From Herbs
The dividing line is the plant part, not the flavor. In the kitchen, herbs are the leafy green or flowering parts of a plant, used fresh or dried.1Wikipedia. Herb Spices are usually dried and made from other parts, such as seeds, bark, roots and fruits.2Wikipedia. Herb People have long used them both to season food and to help preserve it.3Joseph Flach & Sons. Difference between Botanicals, Herbs and Spices | Learn With JFS
One plant can give you both. The leaves of coriander are an herb (cilantro), while its round fruits are a spice. Dill works the same way: feathery leaves for the herb, seeds for the spice. Fennel fronds taste herb-like, while fennel seeds are a classic spice.
The words themselves cause some confusion. “Spicy” in the hot sense is not what makes something a spice, and many spices, like cinnamon and nutmeg, are sweet-warm rather than hot.
Bark Spices Like Cinnamon
Cinnamon is the bark of Cinnamomum trees, peeled and dried into curls or ground into powder. Its aroma is stored in special oil cells concentrated in the inner layer of bark, close to the growing tissue.4PubMed Central. Integrated transcriptomics and metabolomics analysis provides insights into aromatic volatiles formation in Cinnamomum cassia bark at different harvesting times The main flavor compound makes up about two-thirds to three-quarters of cinnamon’s aromatic oil.5Applied Food Research. Optimized HPLC-DAD method for quantifying Coumarin and Cinnamaldehyde in local cinnamon sample It is harsh to the tree’s own living cells, so those oil cells have toughened walls that wall it off.6Plant Production Science. Histochemistry and Cell Wall Specialization of Oil Cells related to the Essential Oil Accumulation in the Bark of Cinnamomum cassia Presl. (Lauraceae)
Getting from tree to stick takes some handwork. Young shoots are cut and the outer bark is scraped away. The inner bark is then peeled in strips, which curl as they dry.
Most cinnamon in supermarkets is cassia, while Ceylon, or “true,” cinnamon comes mainly from Sri Lanka. They are different species of Cinnamomum. In the US, a jar labeled just “cinnamon” is usually cassia, and the label rarely says so. You have to look for “Ceylon” or the Latin name, Cinnamomum verum, on the jar.
The two also differ in coumarin, a natural compound that can strain the liver in large regular amounts. It is under 0.004% in Ceylon cinnamon but can reach 1% in cassia.7Applied Food Research. Optimized HPLC-DAD method for quantifying Coumarin and Cinnamaldehyde in local cinnamon sample Still, coumarin in cassia varies widely, even between packages and within a single tree.8PubMed. Quantification of flavoring constituents in cinnamon: high variation of coumarin in cassia bark from the German retail market and in authentic samples from indonesia So if you eat cinnamon daily, in oatmeal or supplements, choosing Ceylon limits coumarin. Occasional baking with cassia is not a worry for most people.
The sticks look different too. Cassia is a single thick, hard, dark curl. Ceylon is made of thin, papery layers rolled like a cigar, and it crumbles easily. Ceylon tastes milder and more floral, while cassia is stronger and spicier, which is why cassia holds up in boldly flavored baking and savory braises and Ceylon suits custards, fruit and lightly spiced drinks. Ceylon is typically costlier, partly because its thin quills take so much labor to make.
Seed and Fruit Spices
Peppercorns are the berries of the Piper nigrum vine. White pepper is the seed left after the berry’s outer skin is removed,9PubMed Central. A review on conventional and biotechnological approaches in white pepper production and the usual way to do that is soaking the berries in water until the skin softens.10PubMed Central. A review on conventional and biotechnological approaches in white pepper production Black pepper keeps the skin, so white pepper often tastes earthier and less bright.
Ground pepper fades fast. Its aroma sits in volatile oils that escape into the air once the peppercorn is cracked, so a pre-ground jar has been losing aroma since it was filled. The sharp bite comes from a different compound that lasts longer, so old ground pepper tends to taste hot but flat rather than fully empty. A pepper mill gives you freshly cracked peppercorns at the table, and adding pepper near the end of cooking preserves more aroma than boiling it for a long time.
Mustard turns hot only when crushed. Whole seeds store mild, stable compounds in one set of cells and an enzyme in separate compartments.11CSIR NET LIFE SCIENCE COACHING | NTA NET LIFE SCIENCE | CSIR LIFE SCIENCE. Why Mustard Seeds Become Pungent Only When Crushed Crushing breaks the barriers, letting the enzyme turn those compounds into the sharp, nose-tingling ones.12PubMed. The effect of processing on the glucosinolate profile in mustard seed Dry whole seeds therefore taste mild, while ground seed mixed with water develops heat.
Letting ground mustard stand a few minutes in cold water builds the sharpness. Adding vinegar or heat halts the reaction, so a mustard mixed with vinegar from the start stays milder than one mixed with water and left to develop. Cooking whole seeds in hot oil, a standard Indian technique, gives a nutty, mellow flavor instead, and you hear them pop as they go.
Nutmeg is the seed of the Myristica fragrans tree, and mace is the lacy red coat wrapped around it.13PubMed Central. Does fixed oil impart more antioxidant potential to spices than essential oils? A comparative study with seed (nutmeg) and aril (mace) oil from the spice myristica fragrans A whole nutmeg grated on a fine grater is far more fragrant than the jarred kind. The lacy red coat tastes like a gentler, more delicate nutmeg, so use them in similar dishes, saving the mace for light sauces.
Cardamom hides its seeds. Each pod holds about 15 to 20 small dark seeds,14Diaspora Co.. How to Use Cardamom Pods in Every Dish and almost all the flavor is in those seeds, while the husk adds little.15Diaspora Co.. How to Use Cardamom Pods in Every Dish Crack the pods before adding them, or grind just the seeds. For seeds like cumin and coriander, dry-toast them in a pan until fragrant, let them cool, then grind in a spice grinder or mortar.
Flower Spices Like Saffron and Cloves
A clove is a dried flower bud of a tree in the myrtle family.16PubMed Central. Clove Buds Essential Oil: The Impact of Grinding on the Chemical Composition and Its Biological Activities Involved in Consumer’s Health Security The nail shape is the bud’s stem, with the closed petals forming the round head. Fresh cloves feel slightly oily and release scent when pressed. Old ones are dry, brittle and faint.
Saffron is the dried red stigmas, the threads at the center, of the Crocus sativus flower.17PubMed Central. Detection of Saffron’s Main Bioactive Compounds and Their Relationship with Commercial Quality Its color, taste and aroma come mainly from three compounds: crocin, picrocrocin and safranal.18South African Journal of Botany. Nutraceutical and cosmetic applications of bioactive compounds of Saffron (Crocus Sativus L.) stigmas and its by-products It colors and flavors dishes such as Spanish paella, Milanese risotto and Swedish saffron buns.19PubMed Central. Detection of Saffron’s Main Bioactive Compounds and Their Relationship with Commercial Quality
Hand labor drives the price. One kilogram of dried saffron takes 110,000 to 165,000 flowers.20PubMed Central. Detection of Saffron’s Main Bioactive Compounds and Their Relationship with Commercial Quality That means about 50 hours to pick the flowers and 200 more to pull out the threads.21PubMed Central. Detection of Saffron’s Main Bioactive Compounds and Their Relationship with Commercial Quality Saffron sells for roughly 1,500 to 2,200 euros per kilogram.22PubMed Central. Detection of Saffron’s Main Bioactive Compounds and Their Relationship with Commercial Quality The plant is also sterile and must be grown from bulbs, which adds to the work.
The color and aroma compounds dissolve into liquid, so a small pinch can flavor and tint a whole pot of rice for several people. Recipes usually call for a few dozen threads at most, and using more wastes money and risks the flavor. Too much tastes bitter or medicinal.
To use it well, steep the threads in a few spoonfuls of warm water or broth before adding them. The liquid turns deep golden-orange as the color releases. Whole threads are easier to judge than powder because you can see their deep red color and uniform shape, and very cheap saffron is a warning sign of fakes like dyed safflower.
Ginger and Turmeric Are Not Roots
Turmeric is often called a root, but that is technically wrong.23McCormick Science Institute. Turmeric It is a rhizome, a stem that grows sideways underground with small roots growing from it.24McCormick Science Institute. Turmeric New branches sprout from a rhizome, which sets it apart from true roots like carrots or beets.25Willy Street Co-op Reader. Where Do Spices Come From: Bark, Seeds, and More Ginger is the other rhizome most grocery stores sell.26Willy Street Co-op Reader. Where Do Spices Come From: Bark, Seeds, and More
At the store, look for knobby “fingers” branching off the main piece, and small rings along the skin that mark stem segments. Buds on those pieces can sprout into new plants, which carrots can’t do. That is why a forgotten piece of ginger in the fridge may grow pale green shoots from its tips, and why anyone who wants to grow them can plant a piece with a visible bud.
Ginger and turmeric are relatives, and both store high levels of active compounds in their underground stems.27PubMed. Biosynthesis of curcuminoids and gingerols in turmeric (Curcuma longa) and ginger (Zingiber officinale): identification of curcuminoid synthase and hydroxycinnamoyl-CoA thioesterases In ginger these are gingerols, the source of its bite; in turmeric they are curcuminoids, the source of its color.28PubMed. Biosynthesis of curcuminoids and gingerols in turmeric (Curcuma longa) and ginger (Zingiber officinale): identification of curcuminoid synthase and hydroxycinnamoyl-CoA thioesterases
Fresh ginger is juicier and brighter, while dried ground ginger is warmer. Turmeric stains hands and cutting boards yellow, so wear gloves. Store fresh pieces in the fridge, or freeze them and grate straight from frozen.
Spices From Sap and Cured Pods
Asafoetida is a gum-resin from Ferula plants, relatives of carrots.29PubMed Central. Biological activities and medicinal properties of Asafoetida: A review Growers expose the top of the large root, cut the stem off, and cover it.30PubMed Central. Biological activities and medicinal properties of Asafoetida: A review Milky juice oozes out and is scraped off, and a fresh slice is cut to release more.31PubMed Central. Biological activities and medicinal properties of Asafoetida: A review Raw resin is hard and sticky, so it is usually sold as hard lumps or ground and blended into a powder that is much easier to measure.
It smells strongly sulfurous raw but turns onion-garlic savory once fried in oil, which is why it substitutes for onion and garlic in some Indian cooking, especially where those are avoided. Use a tiny pinch, often labeled hing, and always fry it briefly in hot fat first. Keep the jar tightly sealed, because it can scent a whole cupboard. Some brands mix in wheat flour, so check the label if you avoid gluten.
Vanilla beans are pods of a climbing orchid, and they taste of little when picked green. Green pods hold vanillin bound to sugar, and an enzyme must free it.32PubMed. Enzymatic extraction and transformation of glucovanillin to vanillin from vanilla green pods Curing activates that enzyme, and its activity rises during the sweating stages.33PubMed. Biochemical, micro and ultrastructural changes in vanilla pods (Vanilla planifolia, Andrews) during the curing process The weeks of sweating and drying help explain vanilla’s price.
Good pods are soft and oily, not dry and brittle. Split the pod and scrape out the tiny seeds, then simmer the empty pod in milk or sugar to pull out more flavor.
Why Spices Taste So Strong
Plants evolved strong chemicals to deter microbes, insects and grazing animals.34Robust Madagascar. Why Spices Are Called Plant Poisons: The Science Behind Flavor, Defense, and Human Adaptation The bitterness, pungency and burn we enjoy are those defenses at doses we like. A spice’s germ-fighting power comes from many compounds working together, not one.35PubMed Central. Beneficial Effects of Spices in Food Preservation and Safety
Where a plant grows changes its flavor. Basil grown in sandy soil made more aromatic oil than basil in clay soil,36PubMed Central. Impact of soil types on chemical composition of essential oil of purple basil and bay leaves from different altitudes and climates have noticeably different oil profiles.37Journal of Food Composition and Analysis. Lebanese bay leaves (Laurus nobilis): A unique chemotypic and pharmacological profile with culinary and medicinal potential The same spice from different regions can therefore taste different.
Age matters as much as origin. Whole seeds and bark stay good for about two to three years, while ground spices fade within about a year. Whole spices hold their flavor much longer than ground ones, because grinding exposes the aromatic oils to air. Buying whole and grinding as needed gives you stronger flavor. If the aroma is weak, the flavor will be too.
Chili heat changes other tastes. Capsaicin, chili’s hot compound, dulls bitterness far more than hot temperature does,38PubMed. Deconvoluting physical and chemical heat: Temperature and spiciness influence flavor differently so a little chili can soften bitter flavors in a dish.
Capsaicin does not work on taste buds but on pain-sensing nerve endings that also detect heat, which is why chili feels like burning rather than a flavor. Because it dissolves in oil, water barely helps, while milk, yogurt or fat washes it away better.