Anise and fennel seeds are both small and oval. The main difference is in the color of ripe seeds. Ripe anise seeds are a gray-green color, whereas fennel seeds turn brown when they ripen. Additionally, fennel seeds are ribbed and anise seeds are not.
Made into an infusion, anise and fennel seeds both provide relief from indigestion and excess gas. Anise seeds help to freshen breath, relieve cold and cough symptoms, treat nausea and colic and stimulate breast milk. Fennel seeds are beneficial for appetite suppression and sore throats and are infused as a mouthwash or eye compress.
Anise and fennel seeds are used to flavor breads, cakes and other baked goods. Common uses of both include flavored butters, eggs and cheeses. Pickles, curries, stews and flavored liqueurs use anise seeds. Fennel is a common flavoring in sausages, sauerkraut, rice and vegetables.