Lentils

Changed on: 24.10.2016
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Linsenpflanze mit Blüten und Hülsen

Only seven species of lentils exist worldwide, namely: the cultivated lentil, Lens culinaris Medik, the wild lentil, Lens ervoides (Brign.), Lens himalayensis Alef. (only found in India), Lens kotschyana (Boiss.) Nab., Lens lamottei Czefr. (native to Morocco, France and Spain), Lens montbretii (Fischer & alli) P. Davis & Plitmann (native to Western Asia) and Lens nigracans (M. Bieb.) Godr (from the Mediterranean region). The cultivated lentil, Lens culinaris, was an old crop plant in Austria. However, it is hardly cultivated anymore and is seldom and infrequently found growing wild in Vienna, Upper Austria and Vorarlberg.

More information
caption
Linsenpflanze mit Blüten und Hülsen

Only seven species of lentils exist worldwide, namely: the cultivated lentil, Lens culinaris Medik, the wild lentil, Lens ervoides (Brign.), Lens himalayensis Alef. (only found in India), Lens kotschyana (Boiss.) Nab., Lens lamottei Czefr. (native to Morocco, France and Spain), Lens montbretii (Fischer & alli) P. Davis & Plitmann (native to Western Asia) and Lens nigracans (M. Bieb.) Godr (from the Mediterranean region). The cultivated lentil, Lens culinaris, was an old crop plant in Austria. However, it is hardly cultivated anymore and is seldom and infrequently found growing wild in Vienna, Upper Austria and Vorarlberg.

More information

Botany

The lentil, Lens culinaris Medik, belongs to the Fabaceae/Leguminosae family, also known as Papilionaceae or pulses.
 
The annual lentil plant usually grows erect, 15 – 50 cm tall and carries branches from the bottom upwards. The leaves are alternate and paripinnate, with a simple tendril instead of the end-leaf. However, the plant either does not or seldom climb, despite the tendrils at the end of the leaves. The two-to-seven pairs of oblong-linear leaflets have a smooth margin and short petioles. There are also small stipules (3-7 mm) with white hairs.

The inflorescence consists of one to three papilionaceous flowers, typical for this family. The blueish-white corolla is relatively small, measuring only 5-6 mm and is bordered by the green calyx petals. The pointed teeth of the calyx petals are twice as long as the calyx tube. The main flowering period is in June. Lentils are mainly self-fertile, pollination by bees or bumble bees is rare. The pod formed after pollination is rhombic, flat, 8-15 mm long and 4-8 mm wide. It only contains one or two discus-shaped, flat, brownish-green to grey-brown, reddish or yellow, monochrome or finely mottled or speckled seeds.

Nutrients


Lentils are healthy and have a particularly high nutritional value thanks to their high levels of protein (ca. 25 %) and carbohydrates (ca. 60 %) and only small percentage of fat (ca. 2 %). Additionally, they have high levels of vitamins, fibre and minerals. The provitamin A contained in lentils is transformed by the body into vitamin A – important for our eyes and the immune system. Lentils are rich in B vitamins, which are important for stimulating and strengthening neural functions, and also in vitamin E, which protects cells. Moreover, they are rich in potassium, calcium, magnesium, phosphor, iron and zinc. Lentils are also very filling thanks to their high levels of carbohydrates.

Raw lentils contain indigestible, toxic ingredients, so-called lectins, which are neutralised by boiling or heating to a temperature of 75 °C.

Past and present uses

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Thome'sche Flora (1885): Lentil

Lentils are among the oldest crop plants. They have always been used for human consumption in the form of stews, soups and vegetables. It is the round, mostly flat seeds of the lentil plant that are eaten. Dried lentils are excellent for storage as they keep for at least one year when stored in a cool, dry, airy, dark place. While being shunned as food for poor people in the past, lentils have undergone a recent renaissance. The various varieties are an important element in Mediterranean, Asian and Indian cuisine.

Lentils must be cooked before consumption, but not necessarily soaked. In Austria, canned, pre-soaked products predominate. However, the dried seeds can also be turned into tasty soups, stews or salads without much effort.

The various types of lentils are classified according to their colour, size and origin for purposes of sale. Green lentils are the fresh, unhusked fruit with a yellow core. Once husked, they become yellow lentils. Fresh seed begin to change their colour to brown gradually with time and turn into the classic brown variety. Red lentils are usually husked when they are sold in shops. Unhusked, the bright orange-red seed of the fruit is covered in a lilac to brownish husk. The small, black Beluga lentils are particularly aromatic.

In addition, lentils can also be categorised by size. Giant lentils measure about 7 mm in diameter. Flat lentils have a diameter of 6-7 mm, medium lentils 4.5-6 mm and the more bulbous sugar lentils have one of about 4 mm. Furthermore, lentils often have regional names. The tiny Puy lentils, which are grey-green on the outside and yellow on the inside, come from the Auvergne region and are named after the region’s capital. Red-brown mountain lentils have a firm texture and remain al dente after cooking. Alblinsen (Swabian Jura lentils) were cultivated mainly in the Swabian Jura region until World War II.

Agricultural aspects

The lentil plant requires a warm, dry climate with favourable rainfall distribution during its vegetation period for optimum growth. It prefers soils with little clay, gravelly soils, muschelkalk and sandy, chalky soils. Lentils are plants for dry soils that are poor in nutrients where other crops do not grow. Nutrient-rich soils lead to lush, vegetative growth with few pods and seeds and are not suitable for growing lentils for seed.

Lentils are often part of mixed cultivation. They require a loose, medium-fine, weed-free seed bed. They  can resist temperatures between -5 to -9° C, making them an arable winter crop in mild climate regions such as the Mediterranean region. In regions with tough winter conditions, lentils are planted at the beginning of spring. The seeds are planted 4-5 cm deep and at a seed rate of 80-100 kg/ha (large-seeded varieties) or 40-60 kg/ha (small-seeded varieties) between the end of April and the beginning of May, using conventional cereal drill-machines. Spaces between rows should be 15-35 cm. Germination will start at temperatures of 4 to 5° C.

Nitrogen fertiliser is not usually necessary as lentils are legumes, but they require about 11 kg/ha of phosphor and about 14 kg/ha of potassium. Cultivation breaks of four to six years should be maintained before replanting lentils or other Fabaceae species. Lentils are planted best as a following crop to cereals or in areas prone to weeds as a following crop to root vegetables (potatoes, in particular).

Given the lentil’s irregular maturing from bottom to top, it is difficult to pick the right time for harvesting. Lentils are harvested using a combined harvester as soon as the lower pods have turned brown and the seeds have become hard. The stalks and leaves are usually still green at that point of time.

A symbol of variety

The European database for genetic resources (http://eurisco.ipk-gatersleben.de) currently lists 8,249 Lens culinaris accessions, which are primarily kept in gene banks in Russia, Turkey and Hungary. The Austrian index for genetic resources (Index Seminum) lists three lentil origins (www.genbank.at/nationales-verzeichnis.html).

Literature

Literature

Bayerische Landesanstalt für Landwirtschaft (2014) Linse Anbau und Verwertung: www.LfL.bayern.de

Becker-Dillingen J. (1956) Handbuch des gesamten Gemüsebaues, einschliesslich der Küchenkräuter. Verlagsbuchhandlung Paul Parey, Berlin.

Berendes J. (1902) Des Pedanios Dioskurides aus Anazarbos Arzneimittellehre in fünf Büchern. Übersetzt und mit Erklärungen versehen. Volltext; Digitalisat: http://www.pharmawiki.ch/materiamedica/

Fischer M. A., Oswald K., Adler W. (2008) Exkursionsflora für Österreich, Liechtenstein und Südtirol. 3. Auflage. Biologiezentrum der Oberösterreichischen Landesmuseen, Linz.

Körber-Grohne U. (1994) Nutzpflanzen in Deutschland.  Kulturgeschichte und Biologie. 3. Auflage. Konrad Theiss Verlag, Stuttgart.

Lebensministerium (2006) Richtlinien für die sachgerechte Düngung. Anleitung zur Interpretation von Bodenuntersuchungsergebnissen in der Landwirtschaft. 6. Auflage: http://www.ages.at/fileadmin/AGES2015/Service/Landwirtschaft/Boden_Datein/Broschueren/SGD_6_Auflage.pdf

Statistik Austria (2015) Anbau auf dem Ackerland  2015: http://www.statistik.at/web_de/statistiken/wirtschaft/land_und_forstwirtschaft/agrarstruktur_flaechen_ertraege/bodennutzung/020291.html

http://bibd.uni-giessen.de/gdoc/2000/uni/p000003/linse.htm

www.genbank.at

www.naehrwertrechner.de

Pollenfotos siehe http://ponetweb.ages.at

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