Rye is a crop not as old as wheat or barely. Rye was not known among ancient Greeks or the culturally advanced nations of Asia. Thousands of years ago the crop was a weed in the wheat and barley fields of Western Asia. In the course of time the annoying weed came to resemble more a domesticated plant as it grew as an annual plant - the spring rye. Despite the fact that its grain grew larger and the stem of the ear gained strength, rye was still paid no attention. When wheat was imported from Western Asia to European fields, rye was brought along as a weed. Due to the less fertile soil and cooler climate of Central Europe rye gained the majority in wheat fields - rye flourished in the conditions and asserted dominance over not so hardy wheat. The high-tolerance and endurance of rye drew people’s attention and thus rye was recognised as an individual grain cultivar. All that took place in the first millennium B.C. Meanwhile, rye spread further to Northern Europe.
Rye is the national grain of Estonia and, above all, signifies the daily bread. In the first millennium A.D. rye was just a weed in Estonian grain fields. The cultivation of rye as an individual crop cultivator started only in the 11th century. In the course of centuries black bread made of rye came to be the major nourishment in Estonia and rye has been the most sacred crop for hundreds of years.
The amount of rye cultivated in Estonia is enough for domestic consumption and thus it is ensured that the bread that Estonians eat is made of grain grown in our homeland.
Nowadays 95% of rye production originates from the territory between Ural Mountains and the Rhine River. The largest producers are Russida, Poland, Germany and Belarus. In Finland, Lithuania, Latvia and Estonia rye is mostly grown for the residents’ own consumption. The main rye cultivator of the Americas is Canada.
Over the period from the Second World War to the change of the century the growing area of rye has decreased from 36 million ha to 8.5 million ha. However, over the same period its productivity has increased from 11 q per ha to 27 q per ha. About half of the total harvest is used for making bread; the other part includes seed, forage and raw materials for distilleries and the plastic industry.
The nutritional value of rye bread is dependent on the chemical properties of rye, rye flour and bread. Rye bread is considered as very healthy for it contains lots of essential vitamins and minerals (B vitamins, phosphorus, iron, magnesium and zinc). What is more, its fibre content is also considerably high.
Consuming enough rye bread and other grain products ensures a balanced diet. Fibre absorbs water and makes you feel full, making it thus easier to control your appetite. Plus fibre strengthens gums and thus contributes to healthy teeth. Eating rye bread reduces the risk of cardiovascular diseases and cancer. Most of all, it reduces the risk of cancer of the large intestine. Fibre speeds up digestion and as a result the time during which carcinogens come into contact with intestines is shortened. Fibre also reduces glucose and insulin content in the blood, thus lowering the cholesterol level.
Good-quality rye does not contain much cellulose (2-2.5%). Principal water-soluble components of the grain are carbohydrates (64-65%, mainly sugar), proteins (20-25%) and minerals (5-6%).
Rye is an annual winter-hardy domesticated plant that can be grown in the fields all year round. It is the most durable of grains, the height of which is 60-200 cm. Rye is a very undemanding grass which grows well in fields of lesser soil fertility. Expenditure on fertilisers and plant protection products are smaller for rye than for other grains. In addition, rye is extremely winter-hardy.
There exist spring and winter varieties of rye of which the winter variety is more widely used. This means that rye sown in autumn sprouts and winters under the snow cover. In spring it continues to grow and by late summer rye heads are ready for harvesting. The shade of rye flour depends on the colour of rye grains. The preferred shades are yellowy grey and yellow.
For decades Estonian plant breeders have created rye species of a steadily high harvest potential which fit well into the Estonian climate and are competitive in the foreign market. The following rye species have been bred in Estonia: Sangaste, Vambo, Tulvi, Elvi, etc.
Rye is used to make flour of different grinding ranks (e.g. whole grain, brown, white) and to make various foods of which bread is one of the most traditional ones (whole grain, hard-crust, fine-flour, etc.). Rye gives the highest straw yield of grains. In the past when grain was threshed by hand with a flail, long rye straws were used for making thatched roofs. Rye straws have also been used for braiding straw hats. It is possible to make paper and cardboard of rye straw. And in manors rye was used to distil vodka.
Source: Heino Kiik “Maailma viljad” - Valgus, 1989;, Eesti Rukki Raamat - Ilo Kirjastus, 2005