Stevia (Stevia) - Culture Features, Use In Conservation

2024 Author: Sebastian Paterson | [email protected]. Last modified: 2023-12-16 13:47

Among the many beneficial plants that play an extremely important role in human life, serve to maintain human health, stevia can take one of the key places. Experts count almost 400 compounds of high biological activity in this plant. However, at present, the greatest value lies in its ability to synthesize the substance "steviose", which, being a high-quality low-calorie sugar substitute, is completely safe for human health.

Stevia comes from the highlands of northeastern Paraguay and the adjacent regions of Brazil (South America), where there is a lot of heat and moisture, where there is no severe frost. It has been known to mankind since time immemorial - long before the discovery of America by Columbus. The local Guarani Indians added stevia leaves to their wonderful mate tea to give it a sweet taste and an unusually pleasant aroma, calling it "kaa-khe", which means "sweet herb" or "honey leaves". 3-4 small leaves of the plant were enough to sweeten a cup of mate or any other beverage well.

For centuries, this plant remained a mystery to Europeans, as the locals jealously guarded its secret. It was only in 1887 that stevia was literally "discovered" by the South American naturalist Antonio Bertoni. It was later revealed that among the 300 species of stevia growing in America, only one (Stevia rebaudiana) has a sweet taste, which is also its hallmark.

Relatively recently, we managed to get stevia in our country. The famous plant breeder N. I. Vavilov, after long and unsuccessful attempts to get this plant by the official way for VIR, in 1931, it is assumed, illegally brought from abroad several of its flower heads with seeds. However, none of the neatly planted seeds then did not germinate. Only more than half a century later, scientists from the Institute of Sugar Beet (Voronezh) managed to acquire and breed this sweet herb in our country.

The "sweetness" of stevia is determined by the presence in its organs of a diterpene glycoside - stevioside, which is a rather complex compound of a protein nature. Until now, stevioside is considered the sweetest natural compound on the globe. In its pure form, it is 300 times sweeter than sucrose, but at the same time it does not belong to carbohydrates. Without the calorie content and other negative properties of sugar, it is an ideal substitute for both healthy people and those suffering from diabetes, obesity and other metabolic disorders.

In nature, stevia (family Astrovye) is a herbaceous perennial highly branched rhizome plant with drooping stems (60-80 cm high), the tops of which branch well. Every year in the fall, the stems die off, and in the spring they grow back. Stevia has simple narrow leaves arranged in pairs on very short petioles, and small white flowers are collected in a paniculate inflorescence. Freshly picked leaves taste sugary-sweet (20-50 times sweeter than sugar). The content of stevioside in different parts of the plant varies: in dry stems it is 2-3%, in dry leaves - 8-10%.

In its homeland, stevia grows mainly on barren sour sands or on silt, which lies in a strip along the edge of swamps, which indicates its adaptability to various conditions. It is found in places with a moderately humid subtropical climate in the temperature range from -60 to + 43C. The optimum temperature for stevia growth is 22 … 28 ° C. The local level of precipitation is quite high, so the soil there is constantly moist, but without prolonged flooding.

Now in the homeland of stevia, its quantity in natural conditions has significantly decreased due to the increased collection of leaves, grazing, and also due to the export of some of the plants for sale and cultivation on cultivated plantations. The yield of stevioside from the leaves of cultivated stevia is usually 6-12%. Under optimal conditions, the yield of stevia from one hundred square meters is equivalent to 700 kg of table sugar.

Scientists from different countries have proven its safety as a food product. This is confirmed by the use of stevia by the South American Guarani Indians for many centuries. Now its sale is allowed in almost all countries.

For almost half a century, stevia and stevioside have been consumed in large quantities all over the world and there have been no cases of adverse effects on humans.

Its shoots are usually cut at the beginning of flowering. But during the entire growing season, you can take only a few fresh leaves for use so that the plant does not suffer.

Fresh leaves are used to sweeten drinks. And they dry them in the usual way. Then they are crushed in a porcelain mortar, thus obtaining a coarse green powder, which is about 10 times sweeter than sugar (1.5-2 tablespoons of powder replace 1 glass of ordinary sugar). If, however, this powder is additionally passed through the coffee grinder 2-3 times, it will literally turn into dust.

Stevia can be marketed in the form of an extract - a white powder, 85-90.5% consisting of steviziod, which is 200-300 times sweeter than sugar (0.25 tsp of the extract replaces 1 glass of sugar).

Stevia extract can be prepared on your own, but it will be less concentrated (when preparing dishes, it must be added in larger quantities than industrially produced).

Scientists believe that stevia has unique healing and healing properties. The stems and leaves of the plant are widely used in the pharmaceutical industry. Stevia can be used as a tonic (activates the protective functions of the body), to combat obesity, in the treatment of gastritis, gastric ulcer and duodenal ulcer, to weaken the "ulcerative" effect of aspirin tablets, lower blood levels of "bad cholesterol", optimize work gallbladder and kidney and protect liver cells from toxic compounds entering the body.

Experts recommend using stevia preparations as an external remedy for dermatitis, seborrhea, to reduce skin irritation, soften scars from abrasions, small acne, for purely cosmetic purposes to improve the general condition of the skin. The antibiotic properties of stevia preparations can stop (and even suppress) the development of some harmful fungal microflora in the human body. The value of the plant is also high due to its anti-caries qualities: the development of this dental disease is inhibited, and their enamel is protected from destruction.

The complex of some of its properties (heat resistance, quality as a preservative and a sweetener) makes it possible to propose the use of stevia in preparations from plant products - for fruit and berry canning, salting, making sauces, frozen juices, seasonings. Products prepared with the addition of stevia (sweets, confectionery, syrups, teas, drinks, etc.) have no contraindications: they are recommended for use in atherosclerosis, carbohydrate metabolism disorders, obesity and pancreatitis.

Boxes with dried and chopped stevia leaves sometimes appear on sale. They are brewed with boiling water separately or mixed with tea (1: 1), insisted for half an hour. Oregano, mint, St. John's wort or other herbs can be added to stevia. When preserving fruits and berries (in compotes), 6-12 stevia leaves and a quarter of the required amount of sugar are taken in a three-liter jar; when pickling and pickling cucumbers and tomatoes, 5-6 leaves are added instead of sugar before rolling (it is better to add stevia after finishing the heat treatment, just before closing the lid).

The properties of stevia do not deteriorate when heated, so it can be present in all dishes that are exposed to heat, but they try to add its crushed mass to a hot solution, since in cold water it gives off "sweetness" more difficult. The addition of this plant to canned food improves its taste and extends the shelf life. It should be noted that sometimes, to varying degrees, stevia has a bitter (slightly steel) taste. This inherent effect can be noticeably muted by adding sugar in the amount of 8-10% of its usual norm to the preparation. This aftertaste of stevia is more noticeable for fruits and berries, it is not noticed with respect to vegetables.

When preparing sweet stevia syrup, take 7-9 leaves, fill them with water and boil for 40 minutes, then filter and evaporate over low heat (the readiness of the syrup is determined by a drop that does not spread over the glass). Another recipe for making syrup boils down to putting 5-7 g of leaves in a container with a lid and pouring 150 ml of boiling water, covering it, keeping it in a dark place for 20 minutes, straining it. The syrup is stored in the refrigerator, using instead of sugar, adding to drinks, dough, etc.