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Synonym: linseed

botanical name: Linum usitatissimum



The origin of flax is not exactly clear. With the exception of the tropics and very cold regions, it is found in all parts of the earth, either as a cultivated plant or growing wild.

The main areas of cultivation are North America, Argentina, Uruguay, North Africa, India, Japan and the region of the former Soviet Union. The chief exporter is Canada.


Flaxseeds are available throughout the year. They can be bought whole, crushed or roughly ground.

Appearance, taste, characteristics

Flaxseeds are the seeds of the fibre plant flax. Certain varieties are especially suited for obtaining seeds, oil or fibre.

The plant belongs botanically to the family Linaceae. It grows to about 1 m and has bare stalks that stand erect with long, thin blue-green leaves. Between June and August it produces light-blue blossoms, 2–3 cm large, from which round capsular fruits later develop.

The fruits contain red-brown seeds, 4–6 mm long. These seeds are oval, tapered to a slender point on one side and very flat. They have a slightly nutty taste. When they are moistened with water they become slimy.


Flaxseeds are extraordinarily rich in fibre and, compared with other oil seeds, contain less fat. They are rich in protein and have only a minimal amount of water. Further, flaxseeds contain large amounts of magnesium and iron, as well as of vitamin E and some of the B vitamins.

The ingredients of flaxseeds may vary considerably. Large seeds, for example, contain more fat than small ones. The higher linoleic acid content in the fat is considered favourable.

Additionally, the seeds contain phytosterines, phytooestrogens and 6–20% mucins. However, flaxseeds are normally eaten in only small portions, so the nutrient uptake should not be overestimated.

100 g contain:

Energy (kcal)
Water (g)
Protein (g)
Fat (g)
Carbohydrates (g) (g)
Fibre (g)
Vitamin A (RE) (µg)
Vitamin E (mg)
Vitamin B1 (mg)
Vitamin B2 (mg)
Niacin (mg)
Vitamin B6 (mg)
Folic acid (µg)
Potassium (mg)
Sodium (mg)
Calcium (mg)
Magnesium (mg)
Iron (mg)
Saturated fatty acids
Monounsaturated fatty acids (g)
Polyunsaturated fatty acids (g)

Harmful substances

Flaxseeds contain linamarin, a substance that their own enzymes decompose into hydrogen cyanide, among other things. When flaxseeds are eaten, the acidic stomach environment inactivates these enzymes to a large extent, so that the seeds can be consumed in small quantities without hesitation.

Only in the breeding of animals have harmful effects occurred, when larger amounts of soaked flaxseeds and their press cake from oil extraction were used as fodder.

Quality criteria, optimal storage conditions

The seeds should be kept in an air-tight container and stored in a cool, dark place. Coarsely ground flaxseeds become rancid very quickly.

Form of consumption, use, processing, practical tips for preparation

Flaxseeds are used whole, broken or ground. They are eaten alone or mixed with other foods to add fibre to the diet and promote digestion. Dry flaxseeds can absorb a great deal of liquid and have a great capacity to swell. For this reason you should make sure by all means to drink enough while you are eating them or directly thereafter.

Flaxseeds are also used in baked goods and mueslis. In special flaxseed breads at least 8% of the flour is enriched with flaxseeds.

Flaxseeds belong to the group of oil seeds, because they are used primarily to extract oil. The edible oil is called linseed oil and is sold for the most part cold-pressed and unrefined. In this form the natural components of the flaxseeds are retained in the oil.

The high-quality edible oil is used only for foods served cold. It has a characteristically spicy flavour, but it turns rancid quickly and should therefore always be kept in a cool, dark place.


Linseed oil is also used in the production of coating compounds and as a raw material for linoleum.

The press cake that results from oil extraction is very rich in protein and is used as animal fodder. However, mucins and the hydrogen cyanide-producing enzyme linamarase are removed from the fodder first.





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