Apium graveolens is a plant species in the family Apiaceae commonly known as celery (var. dulce) or celeriac (var. rapaceum), depending on whether the petioles (stalks) or roots are eaten: celery refers to the former and celeriac to the latter. Apium graveolens grows to 1 m tall. The leaves are pinnate to bipinnate leaves with rhombic leaflets 3–6 cm long and 2–4 cm broad. The flowers are creamy-white, 2–3 mm diameter, produced in dense compound umbels. The seeds are broad ovoid to globose, 1.5–2 mm long and wide.
Uses
Apium graveolens is used around the world as a vegetable, either for the crisp petiole (leaf stalk) or the fleshy toproot.
In temperate countries, celery is also grown for its seeds. Actually very small fruit, these “seeds” yield a valuable volatile oil used in the perfume and pharmaceutical industries. They also contain an organic compound called apiol. Celery seeds can be used as flavouring or spice, either as whole seeds or ground and mixed with salt, as celery salt. Celery salt can also be made from an extract of the roots.
Celery salt is used as a seasoning, in cocktails (notably to enhance the flavour of Bloody Mary cocktails), on the Chicago-style hot dog, and in Old Bay Seasoning.
Celery, onions, and bell peppers are the holy trinity of Louisiana Creole and Cajun cuisine. Celery, onions, and carrots make up the French mirepoix, often used as a base for sauces and soups. Celery is a staple in many soups, such as chicken noodle soup.
Medicine
The use of celery seed in pills for relieving pain was described by Aulus Cornelius Celsus around 30 AD. Celery seeds contain a compound, 3-N-butyl-phthalide, that has been demonstrated to lower blood pressure in rats.
It is thought to be an aphrodisiac by some people, because it is thought to contain androsterone, a metabolic product of testosterone. However, this is a misunderstanding of androstenone.
Bergapten in the seeds can increase photosensitivity, so the use of essential oil externally in bright sunshine should be avoided. However, this is a potentially useful action in psoriasis, with caution, and celery, along with other umbellifers, is one of the vegetables to be included in the diet as a source of psoralens for this purpose according to herbalists. This may constitute a risk factor, though, in skin cancer. The oil and large doses of seeds should be avoided during pregnancy, as they can act as a uterine stimulant. Seeds intended for cultivation are not suitable for eating as they are often treated with fungicides. A common use for the seeds is as a “blood purifier”, and it is sometimes taken for arthritis.
Nutrition
Celery is used in weight-loss diets, where it provides low-calorie dietary fibre bulk. Celery seeds are also a great source of calcium, and are regarded as a good alternative to animal products.
Allergies
Celery is among a small group of foods (headed by peanuts) that appear to provoke the most severe allergic reactions; for people with celery allergy, exposure can cause potentially fatal anaphylactic shock. The allergen does not appear to be destroyed at cooking temperatures. Celery root—commonly eaten as celeriac, or put into drinks—is known to contain more allergen than the stalk. Seeds contain the highest levels of allergen content. Exercise-induced anaphylaxis may be exacerbated. An allergic reaction also may be triggered by eating foods that have been processed with machines that have previously processed celery, making avoiding such foods difficult. In contrast with peanut allergy being most prevalent in the US, celery allergy is most prevalent in Central Europe.In the European Union, foods that contain or may contain celery, even in trace amounts, must be clearly marked as such.