65,438+0. High available energy. The metabolic energy of corn is 14.06 MJ/K8, and the highest can reach 15.06 MJ/kg, which is the highest among cereal feeds. This is mainly because there is very little crude fiber in corn, only 2%. The nitrogen-free extract is as high as 72%, and the digestibility can reach 90%. On the other hand, the crude fat content of corn is relatively high, ranging from 3.5% to 4.5%.
2. The linoleic acid content is high. The content of linoleic acid in corn is 2%, which is the highest in grain feed. If the proportion of corn in the diet is above 50%, only corn can meet the requirement of linoleic acid for pigs and chickens (1%).
3. The content of protein is low and the quality is poor. The content of protein in maize is about 8.6%, with unbalanced amino acids and insufficient contents of lysine, tryptophan and methionine.
4. Minerals About 80% of minerals exist in embryos, and the calcium content is very small, about 0.02%; The content of phosphorus is about 0.25%, but about 63% of phosphorus exists in the form of phytic acid phosphorus, and the utilization rate of monogastric animals is very low, and the content of other mineral elements is also low.
5. Fat-soluble vitamins contain more vitamin E, about 20mg/kg, yellow corn contains more carotene and almost no vitamins D and K.. Water-soluble vitamins contain more thiamine, less riboflavin and nicotinic acid, and nicotinic acid exists in a combined form.
6. The average content of lutein in yellow corn is 22 mg/kg, which is one of the characteristics of yellow corn and is of great significance for coloring yolk, shin and claw.
(2) Feeding value
1. Chicken corn is the most important feed material for chickens, with high energy value, which is most suitable for fattening broilers. Moreover, yellow corn has a good coloring effect on yolk, claws and skin. In the compound feed for chickens, the amount of corn is as high as 50%~70%.
2. The effect of raising pigs with corn is also very good, but excessive use should be avoided to prevent the back fat thickness from increasing due to excessive heat energy. Because corn lacks lysine, lysine should be added to the diet of pigs of any weight.
3. Ruminant corn has good palatability and high energy, which can be widely used in mixed concentrate of cattle, but it is best to use it with other big bran feeds to prevent food accumulation and expansion.
(3) High lysine corn In order to solve the problem of poor quality of corn in protein, breeders all over the world are committed to cultivating high lysine corn varieties. In 1950s, the United States has bred high lysine corn varieties such as Opak-2 and Flory-2, with lysine content above 0.5% and tryptophan content above 0.2%. China also introduced them for trial planting. However, a large number of experiments at home and abroad have proved that high lysine corn can completely or partially replace soybean cake, which is an important way to solve the shortage of essential amino acids in human body.
Corn, also known as corn, big corn, bonzi, corn, corn, Yuling, Yumai, Liugu, millet and pearl rice, belongs to Gramineae. The sown area of corn ranks third in the world, second only to wheat and rice. In China, corn has a large planting area and is widely distributed, and it is one of the main foods for people in mountainous areas in the north and southwest of China and other arid valley areas. Laixi City, Shandong Province is an important producing area of corn.
Corn seeds can be divided into the following nine types according to their morphology, endosperm structure and glume.
1. Hard grain type is also called flint type. Most of the grains are square, with horny endosperm at the top and around, and only the near embryo part in the center is silty, so the appearance is translucent, shiny, hard and full. The grain color is mostly yellow, occasionally purple, red and other colors. The grain quality is good, and it has been cultivated for a long time in China, mainly for eating.
2. Horse tooth shape is also called horse tooth shape. The texture is a flat rectangle. Because the top of the powder dries faster than the keratin on both sides, the middle of the top is concave and looks like horse teeth, so it is named. Grain surface wrinkles are rough and opaque, mostly yellow and white, and a few are purple or red, so the edible quality is poor. It is the most cultivated type in the world and China, and is suitable for making starch and alcohol or as feed.
3. Half-horse tooth type is also called intermediate type. It is a hybrid of hard-grain corn and horse-tooth corn. The depression at the top of the grain is shallower than that of the horse tooth type, and some are just white spots. The silty endosperm at the top is less than that of horse tooth type, but more than that of hard grain type, with better quality and more cultivation in China.
4. Silt mold is also called soft mold. The endosperm is all silty, and the grain is milky white and dull. It can only be used as raw material for making starch, and it is rarely cultivated in China.
5. Sweet corn is also called sweet corn. Endosperm is mostly horny with high sugar content and low starch content. When it matures, the surface of the particle shrinks and is translucent. It is mostly used as a vegetable, but it is not widely cultivated in China.
6. The upper part of sweet flour grains is horny endosperm; The lower part is silty endosperm, which is rarely cultivated in China.
7. Waxy type is also called waxy type. The endosperm of grain is all horny, but opaque and waxy, and almost all endosperm is composed of amylopectin. Food is like glutinous rice, sticky and delicious. There is only sporadic cultivation in China.
8. Bursting seeds are small, rice-shaped or pearl-shaped, the endosperm is almost all horny, the texture is hard and transparent, and the seed coat is mostly white or red. Especially suitable for processing puffed food such as popcorn. China has sporadic cultivation.
9. The seeds with barnyard grass are wrapped in a long barnyard grass shell, which is hard and difficult to thresh. It belongs to the primitive type and has no cultivation value.
China's national standards for corn quality are divided into four categories according to the grain color and grain quality of corn:
Yellow corn: Corn with yellow seed coat.
White corn: corn with white seed coat.
Waxy corn: corn rich in viscosity.
Miscellaneous corn: More than 5.0% of the above three types of corn are mixed with corn outside this category.
The history of maize planting and utilization
I. Planting history
Corn, also known as "corn", "corn", "reed" and "pearl rice", originated in South America. Because corn was suitable for dry land planting 7000 years ago, the western European colonists brought corn seeds back to Europe after invading America, and then they were widely planted in Asia and Europe. /kloc-around the middle of the 6th century, China began to introduce corn,18th century.
Second, the classification of corn
There are two main ways to classify corn: by seed coat color and by quality. Details are as follows:
1, China's newly revised national standard and American standard divide corn into yellow corn, white jade rice and mixed corn according to the color of seed coat.
Yellow corn. The seed coat is yellow, including red and yellow corn. According to American standard, the content of other colors corn in yellow corn should not exceed 5.0%.
White corn. The seed coat is white, including slightly yellow or pink corn. In the American standard, light yellow means light straw color, which stipulates that the content of corn in other colors in white jade rice should not exceed 2.0%.
Mixed corn is defined as corn mixed with more than 5.0% corn outside this category in China's national standards. According to the American standard, the color can neither meet the color requirements of yellow corn nor white corn, and it contains yellow corn with white top.
2. According to the quality classification, corn can be divided into conventional corn and special corn. The so-called special corn refers to all kinds of corn except conventional corn. Traditional special corn includes sweet corn, waxy corn and popcorn, and newly developed special corn includes high-quality protein corn (high lysine corn), high oil corn and high amylose corn. Because special corn has higher technical content and greater economic value than ordinary corn, it is called them abroad.
Sweet corn is usually divided into ordinary sweet corn, fortified sweet corn and super sweet corn. Sweet corn has strict requirements on production technology and harvest period, and its shelf life is short. Now China has mastered a full set of breeding techniques and accumulated some germplasm resources, and all kinds of sweet corn bred in China can basically meet the market demand.
Waxy corn. Its production technology is much simpler than sweet corn. Compared with ordinary corn, it has almost no special requirements, flexible harvest period and long shelf life, and does not need special storage and processing conditions. Waxy corn is not only fresh, but also an important raw material for starch processing industry. The breeding and production of waxy corn in China have developed rapidly.
Popcorn.
High-oil corn has high oil content, especially unsaturated fatty acids such as linoleic acid and oleic acid, which can lower serum cholesterol and soften blood vessels. In addition, high-oil corn has higher protein 10- 12%, higher lysine 20% and higher vitamin content than ordinary corn, so it is a multifunctional corn for grain, feed and oil.
High quality protein corn (high lysine corn). The yield is not lower than that of ordinary corn, but the lysine content of whole grain is 80- 100% higher than that of ordinary corn. In some areas of China, the combination of high yield and high quality has been achieved.
Purple corn is a very rare corn variety and a special product of our country. It is called "black pearl" because of its pearl-like particles. Although the quality of purple corn is excellent and unique, there are few sticks and small grains, and the yield per mu is only about 50 kg.
Other special corn and improved corn varieties, including high starch special corn, silage corn and edible corn hybrid varieties.
Third, use history.
1, overview of maize utilization
As far as the utilization of corn is concerned, it has gone through three stages as human rations, livestock feed and raw materials for industrial production.
Ration consumption accounts for about 5% of the total corn consumption, but with the development of the times, this proportion has a downward trend. Corn is one of the three major grain varieties, which plays a great role in solving the problem of food and clothing for human beings. Today, corn is still an indispensable food on the table of people all over the world: in Mexico, the hometown of corn, the annual consumption of "national grain" tortillas reaches 6.5438+0.2 million tons. In developed countries and regions, corn is also widely eaten as a source of iron, magnesium and other minerals necessary for human body. In some poor countries and regions, corn is still a cheap food for people.
Feed consumption is the main consumption channel of corn, accounting for about 70% of the total consumption. This kind of consumption can be regarded as a function of the change of living standard and population with time: in the initial stage of the improvement of people's living standard, Engel's coefficient is high, and the strong demand for meat, eggs, poultry and milk has driven the great development of animal husbandry and feed industry, which has led to a substantial increase in the demand for feed corn and has become the main driving force for increasing corn production; When the living standard reaches a certain level, the Engel coefficient will decrease, and the demand for meat, eggs, poultry and milk will remain stable. At this time, the consumption of forage corn will only be proportional to the population.
As an industrial raw material, corn is also the main channel of corn consumption. Corn is not only the "king of feed", but also the most widely used industrial raw material in grain crops, with the largest number of products to be developed and the largest consumption. Using corn as raw material to produce starch, the products with the best chemical composition and the lowest cost can be obtained, and the added value is dozens of times higher than the original value of corn, which is widely used in papermaking, food, textile, medicine and other industries. Alcohol produced from corn starch is clean. "
Inventory is also a form of corn demand. Considering food security, the state always reserves some food. World corn stocks generally account for about 20% of consumption. In recent years, China's corn stock is about 6-7 million tons.
2. Current situation of maize utilization in the world
The overall situation of corn utilization is that industrialized countries use a large proportion as feed, while developing countries use a large proportion as rations.
With the great development of animal husbandry and feed industry in the world, the demand for feed corn in the world is increasing. In developing countries, the consumption of industrial feed corn has increased, and the consumption of feed corn fed to livestock and poultry in the traditional way has also increased. In developed countries and regions, a large number of corn grains have been processed into industrial feed.
Judging from the trend of corn consumption in the world, in recent 15 years, corn used as feed has been increasing year by year in both developing and developed countries, while the amount used as rations has been decreasing, while corn used as industrial raw materials and food processing has been increasing. Take China as an example: in the early 1990s, the feed industry and animal husbandry developed rapidly, and the consumption of feed corn reached 62 million tons in 1993, accounting for 67% of the total corn consumption.
In 1980s, there were 264 million tons of corn used as industrial feed, 66 million tons of corn used as rations and 44 million tons of corn used as industrial raw materials in the world. In the 1990s, the above three indicators were 352 million tons, 59 million tons and 56 million tons respectively.
1996, American industrial feed production consumed1270,000 tons of corn, accounting for 53% of the total corn output. Europe consumes 66 million tons of feed corn, China consumes 34.98 million tons, Japan consumes16.62 million tons, Brazil consumes1520,000 tons, and France.
America's corn production accounts for 40% of the world's total output. Looking at the consumption trend of American corn market for decades, we can see that in 1950s, 85.7% of American corn products were used as feed, 8.08% were industrial raw materials and food, and 5. 17% were exported. In 1960s, feed corn accounted for 8 1.76%, industrial raw materials and food accounted for 8.23%, and export accounted for 12.38%. In 1970s, feed accounted for 66.02%, industrial raw materials and food accounted for 8.77%, and export accounted for 25.2 1%. From 1980s to early 1990s, corn used as feed accounted for 59.36% (1223,700 tons), industrial raw materials and food accounted for11.65% (240100000 tons), and exports accounted for 28.63% (59000 tons).
Since China's reform and opening up, with the great development of animal husbandry, the improvement of people's living standards and the development of corn industry, corn has become a multi-purpose crop of grain, feed, industrial raw materials and export commodities.
In the 1980s, the proportion of corn consumption in China was 38% in rations, 25.88 million tons in corn consumption, 48% in feed (industrial feed and traditional feed), 32.69 million tons in corn consumption, 654.38+065.438+0% in exports, 7.49 million tons in exports, 3% in industrial raw materials and food processing, and about 2.05 million tons in corn consumption.
In the 1990s, the proportion of people directly consuming corn was declining. The national corn ration consumption accounts for about 19% of the total corn output, and the corn consumption is about187,000 tons. In China, there are two ways to consume corn as feed. First, processing and producing compound feed. In recent years, the output of compound feed in China is about 48 million tons, and the annual consumption of corn is 28.8 million tons at a rate of 60%. The other is the traditional corn eaten directly as feed. In rural areas, corn is mainly used as feed to feed large livestock, pigs and poultry. According to experts' estimation, this traditional feeding method consumes about 35 million tons of corn every year.
Corn is an important industrial raw material and can also be processed into refined corn food. At present, the corn used in industrial raw materials and food industry in China accounts for about 5% of the total corn output, and the annual consumption is about 2.5 million tons. From 1990 to 1994, the average export volume of corn in China was 8.2 million tons. It accounts for about 8% of the total corn output. After 1995, a large number of corn was imported. In recent 10 years, the trend of corn consumption in China is that the number of corn used to produce compound feed has increased sharply, while the corn used for rations has decreased year by year, and the corn used for industrial raw materials and food processing has grown slowly, from corn exporting countries to corn importing countries.
3. The new trend of maize utilization in China.
Since the 1980s, China has begun to attach importance to and develop the corn deep processing industry, introduced technology and equipment successively, and built a number of corn deep processing enterprises with a production scale of over 654.38+10,000 tons. Jilin Province has implemented the "Million Tons of Corn Deep Processing Project", taking the corn deep processing industry as the pillar industry. A joint venture between Ji Fa Group and Hong Kong businessmen has an annual processing capacity of 400,000 tons. It has become the largest corn processing enterprise in Asia. Although China's corn deep processing industry has made initial progress, there is still a big gap compared with advanced countries in the world. Take Jilin Province as an example: from 1979 to 1998, the grain processing and transformation volume in Jilin Province increased from1590,000 tons to 6 million tons (including 4.4 million tons for livestock and feed processing). The main corn production in Jilin Province increased from 9.03 million tons to 25.06 million tons, with an average annual increase of 840,000 tons. Compared with the latter, the former is only 28%, and the output is far greater than the consumption. Compared with more than 4,000 kinds of corn deep-processed products with an output value of hundreds of billions of dollars in the United States and other countries, the gap is obvious. However, the production of modified starch and high fructose corn syrup in China has just started, and the alcohol output is not high, so the prospect of corn deep processing is very broad.
Since the birth of Super Girl, it has a second meaning, that is, Super Girl's fans, because her name has the word "jade", and fans have the word "fans", which means "corn".
The word "corn" is an interesting "domain name" on the Internet, especially in the community of "domain investors". They prefer to call the domain name "corn" and the domain name "boiled corn". These people who specialize in "cooking corn" naturally become "corn bugs"
Longevity food named "China Yishou Recipe"-Corn
Other cuisines belonging to this cuisine
Types of healthy recipes
Corn is the seed of Gramineae corn, also known as corn, Henan wheat, Hongyan wheat, coix seed and so on. Sweet in taste and flat in nature, it has the functions of regulating appetite, benefiting lung and calming heart, clearing away damp heat, benefiting liver and gallbladder and delaying aging.
Modern research has confirmed that corn is rich in unsaturated fatty acids, especially linoleic acid, up to more than 60%. Synergistic effect with vitamin E in corn germ can reduce blood cholesterol concentration and prevent it from depositing on blood vessel wall. Therefore, corn has certain preventive and therapeutic effects on coronary heart disease, atherosclerosis, hyperlipidemia and hypertension. Vitamin E can also promote cell division in human body. Delay aging. Corn also contains a longevity factor-glutathione. With the participation of selenium, glutathione oxidase is generated, which has the functions of restoring youth and delaying aging. Selenium and magnesium contained in corn have anti-cancer effects. Selenium can accelerate the decomposition of peroxides in vivo, so that malignant tumors can be suppressed without molecular oxygen supply. On the one hand, magnesium can inhibit the development of cancer cells, on the other hand, it can promote the excretion of waste in the body and is also beneficial to cancer prevention.
Gramineae corn is panicum miliaceum, commonly known as corn, corn cob and pearl rice. It is an important food and feed crop. Native to Mexico or Central America, it has been cultivated for 4500 ~ 5000 years. But its origin and evolution are still inconclusive. China has been planting corn for more than 400 years. It is said that it was introduced at the beginning of15th century and distributed in the temperate zone between 58 north latitude and 40 south latitude. Subtropical and tropical areas can be planted from basins below sea level to areas above 3600 meters above sea level, of which North America has the most, followed by Asia, Latin America and Europe. Among all kinds of crops in the world, the total planting area and total output of corn are second only to wheat and rice, ranking third, and the output per unit area ranks first in the world. The planting area and output are the first in the United States, the second in China and the third in Brazil. China is concentrated in the direction inclined from northeast to southwest via north China. Summer maize area in Huang-Huai-Hai Plain; Plant morphology of maize; Southwest mountainous corn area; Southern hilly corn area; Northwest irrigated corn area and Qinghai-Tibet Plateau corn area.
Roots are fibrous roots, including radicles and nodal roots. Flowers are unisexual and monoecious. The seed is caryopsis, which consists of pericarp, seed coat, embryo and endosperm. Seeds are yellow, white, purple, red or variegated. Corn likes temperature. The optimum temperature for seed germination is 25 ~ 30℃. Corn is a short-day four-carbon plant, which grows in sandy soil, loam and clay.
The optimum pH value is 6.5 ~ 7.0. Salt-alkali tolerance is poor and chloride ions are harmful. The whole growth period of maize is 90 ~ 150 days, which can be divided into three growth periods: seedling stage, ear stage and flowering stage.
According to the grain shape, endosperm starch properties and barnyard grass shell size, it can be divided into seven types: horse tooth type, hard grain type, sweet type, waxy type, burst type, silt type and barnyard grass type.
Variety improvement adopts methods such as heading and seed selection, mixed seed selection, interspecific hybridization and inbred line hybridization. Inbred lines have strong heterosis and great yield-increasing potential, which are widely used in all countries of the world.
The main planting systems in China's corn areas are: the northeast, northern North China and parts of northwest China are spring corn areas, which are planted once a year; The North China Plain is dominated by summer corn that crops twice a year. The hilly and mountainous areas in southwest and south China have complex topography. Spring corn is harvested once a year in alpine mountainous areas, summer corn twice a year in hilly mountainous areas and autumn corn three times a year in plain shallow mountainous areas. Cultivation methods include monoculture, soybean and potato intercropping, wheat ridge interplanting and so on. Timely early sowing is very important to increase yield. According to the fertilizer and water conditions and variety characteristics, reasonable close planting and ensuring enough seedlings are the key to high yield. Corn needs nitrogen and ears. The residual phosphorus of the previous crop can be utilized, but when the available phosphorus in the soil is lower than 10ppm, phosphorus application will significantly increase the yield. Sensitive to zinc fertilizer, zinc deficiency will inhibit its growth. Water requirement during whole growth stages is 5600 ~ 6 100 mm/ha. The water requirement at seedling stage is less, the jointing and booting stage increases, the tasseling and flowering stage is the most, and the filling maturity stage is more. Corn is not tolerant to waterlogging and should be planted in rainy areas.
There are more than 30 kinds of maize diseases, including leaf spot, head smut, bacterial wilt, virus disease and stem rot. By selecting resistant varieties and strengthening management, it can be prevented. Pests include corn borer, cutworm, mole cricket, red spider, sorghum stem borer, armyworm and so on. We use chemicals to prevent them.
Cereal contains 73% starch, 8.5% protein and about 4.3% fat. There are many vitamins (thiamine, riboflavin). Corn kernels are mainly used for eating and feeding, and can be cooked, ground or made into puffed food. Alcohol, beer, acetaldehyde, acetic acid, acetone and butanol are all used in industry. The syrup made of corn starch is colorless and transparent, with high fructose content, and can be made into candy, cake, bread, jam, beverage and so on. Corn cob can be made into furfural. The stalk can be used for papermaking and sound insulation; Bracts and leaves of ear can be used for weaving handicrafts, and seeds can be used as concentrated feed. The stems, leaves and ears harvested at wax maturity are good silage for livestock, especially cows. The nutritional value and digestibility are higher than those of barley, oats and sorghum.
In addition, the word "corn" often refers to domain names in the network.
Open classification:
Plants, in layman's terms, life, crops and feed are of course acidic!