Anise vs Licorice: What Is the Difference?

Four plants get filed under one flavor. Three of them, anise, star anise and fennel, taste alike because they share a compound. The fourth, licorice root, tastes different and works differently, and it lends its name to all of them.

Anethole: the smell everyone calls licorice

Anise seed oil and star anise oil are both mostly anethole. Fennel seed oil is anethole-led too, with fenchone, which adds a bitter, camphor-like edge, especially in bitter fennel. Anethole tastes sweet on its own, which is why anise reads as a sweet spice even with no sugar present.

It also barely dissolves in water. Ouzo and pastis go cloudy when you add water because the anethole falls out into fine droplets, the "louche". In a liqueur that is the point. In a clear soda it is a defect, so anise flavors for water need an emulsion or a solubilizer.

Star anise is the commercial workhorse. It comes mostly from China and Vietnam and is a cheaper anethole source than anise seed. One caution: Japanese star anise, a related species, is toxic and hard to tell apart once dried. FDA warned against star anise teas in 2003 after dozens of illnesses that it suspected came from the Japanese species. Buy from suppliers who test identity.

Glycyrrhizin: what licorice root actually does

Licorice root carries a trace of anethole, but its signature is glycyrrhizin. It is a sweetener, not an aroma: it arrives slowly and lingers long after sugar has gone. Real licorice extract also brings an earthy, woody, slightly bitter body. That delayed, lingering sweetness is a large part of what people mean when they say stevia tastes "like licorice". See stevia aftertaste.

Because it sweetens and smooths, glycyrrhizin and its ammonium salts are used as a flavor enhancer and to round off bitterness. Root beer uses both families: anethole for the aniseed lift and glycyrrhizin for the slow sweetness.

Why "black licorice" often means anise

US black licorice candy leans on anise for its smell. FDA has noted that many US products sold as licorice or licorice-flavored contain little or no licorice. One widely sold black licorice twist lists licorice extract at 2% or less, alongside natural and artificial flavor, and gets its black from Red 40 and Blue 1.¹ Salty Dutch and Nordic licorice adds a third note again: ammonium chloride, known as salmiak.

What to know before you formulate

• Glycyrrhizin has legal ceilings. In the US, licorice and its derivatives are permitted as flavors and flavor enhancers up to set glycyrrhizin levels, for example 3.1% in soft candy and 0.15% in nonalcoholic drinks. They may not be used as a nonnutritive sweetener in sugar substitutes.²
• Europe requires a warning. Confectionery with 100 mg/kg or more of glycyrrhizic acid must say "contains liquorice". From 4 g/kg it must add that people with high blood pressure should avoid eating too much.³
• It has real health effects. FDA has warned that people over 40 who eat 2 ounces of black licorice a day for two weeks or more can develop an irregular heart rhythm, because glycyrrhizin can push potassium down.⁴ An anise-flavored candy avoids this. A real-licorice one does not.
• Anise is easy to overdo. Anethole is powerful and lingers. In a blend, a small amount reads as warmth; too much and everything tastes of licorice.
• Do not swap one for the other. Anise oil gives the smell without the slow sweetness. Licorice extract gives the sweetness and body without much smell. Many good licorice profiles need both.