Don't look at cassava as a poisonous plant, but in the early years, these cassava alone have fed hundreds of millions of people, so don't underestimate this cassava. Without these cassava, presumably more people would have starved to death before.
When I was young, I couldn't afford rice because my family was relatively poor. So cassava, corn, and sweet potatoes are the foods we eat the most. However, cassava needs to be treated before eating, otherwise it will be poisoned if eaten.
It is said that untreated cassava only needs 1 kilogram to kill an adult. It can be seen that the toxins contained in cassava are still very large, so no one will be stupid enough to eat the kind of cassava that has not been treated.
It is also because cassava is poisonous that Indians are very repulsive. But in our country, as long as it is handled well, even the poisonous cassava can still become a rare delicacy.
Introduction to cassava
Cassava originated in tropical America and is widely cultivated in the tropics and parts of the subtropics. Mainly distributed in Brazil, Mexico, Nigeria, Bolivia, Thailand, Colombia, Indonesia and other countries. It was only introduced in China in the 1820s, and is now widely distributed in South China, with the largest cultivation area in the Two Cantons, followed by Fujian and Taiwan, and a small amount of cultivation in Yunnan, Guizhou, Sichuan, Hunan, Jiangxi and other provinces.
In fact, the cultivation method of cassava is very simple, and there are many forms of cultivation. It can be planted in a flat trench, dug a hole for planting, or it can be planted in a furrow. It is mainly determined according to the local terrain, terrain, soil thickness, drainage conditions, planting scale, management capacity and so on.
Generally speaking, the flat terrain, small slope, poor drainage, low-lying and easy to waterlogging, thin soil layer, shallow tillage layer of the plot should be planted, and the height of the furrow is also determined by the drainage and other conditions.
For the soil layer is deep, soft and ready to plant peanuts, soybeans can be used flat, slope should be horizontal slope, in order to facilitate soil and water conservation, to prevent rain erosion, soil erosion, and high terrain, large slope, drought, good drainage, thick soil layer, deep tillage of the plot can not afford.
There are three ways to grow cassava
Flattening: The seed stem is buried approximately horizontally in a plant ditch or plant hole. It can be distributed horizontally and is prone to high yields. It is suitable for planting in places where the topsoil is shallow and thin, loose and the subsoil is heavy, but because the seed stem is buried in the soil, the ventilation is poor, the germination is difficult, it is easy to cause lack of plants, and the wind resistance is poor.
Oblique cutting: 2/3 of the length of the seed stem is buried at a 15-45 degree angle to the ground into a planting ditch or planting hole. It emerges quickly and has a high emergence rate, but the potatoes are more stretched in one direction, and the harvest is high but the wind resistance is not high, so it is advisable to use this method in places with high humidity and furrows.
Straight insertion: Insert 2/3 of the seed stem vertically into the soil, leaving only 1/3 of the exposed topsoil. It emerges early and in unison, there are many potatoes but uneven, due to the deep soil, good wind and drought resistance, difficult harvest, more flower workers, suitable for deep soil, furrowing situation.
Why is cassava poisonous?
Because cassava contains a substance called flaxseed picrin, poisoning can occur if raw or undercooked cassava is ingested or its soup is drunk. The reason for this is that linoleum picrin or linoleum picrinase is hydrolyzed by gastric acid to produce free hydrocyanic acid, thereby poisoning the human body. A person who consumes 150 to 300 grams of raw cassava can cause poisoning and even death. To prevent cassava poisoning, before eating cassava, the skin is soaked in the potato flesh with water to dissolve the cyanosides. Generally, 70% of the cyanogen can be removed after about 6 days of soaking, and then heated and cooked, and then it can be eaten.
Cassava is poisonous, why has it not been extinct on the mainland?
Cassava is mainly poisonous in its roots, stems, leaves, although its potato is also poisonous, but as long as it is handled properly, its potato is edible, and its taste is still very good, is a rare delicacy.
There are also two reasons why this poisonous cassava has not been removed from the mainland.
First, make starch:
Because the starch content of fresh tapioca is as high as 25-30% (the water content is higher, 20%-28% higher than that of sweet potatoes), and the starch content of dried tapioca is as high as 80%, and starch is still more useful in our daily life, such as we can use it, hanging paste, making candy, vermicelli and so on. In addition, the starch purity of cassava is much higher than that of sweet potatoes, so it is the best choice for making starch.
Second, industrial needs:
In addition to making cassava into starch, it also has a great role in industry. For example, tapioca starch-based syrup can be produced at low cost through acidolysis or enzymatic process, which can be used as a raw material for the production of various chemicals such as sodium glutamate, amino acids, organic acids, ethanol, ketones, vitamins and antibiotics.
Summary:
Although cassava is poisonous, as long as it is treated at high temperatures, cassava can be eaten directly. In addition, cassava has a high sediment content, so it is also a "tonic"! And even if you want to eat cassava now, it's really difficult! Especially for people living in the city, it is really not easy to eat a meal of cassava, because there is no need to sell it in the market.