The Yellow Emperor's Neijing Su Qing says: "Poison attacks evil, five grains are nourished, five fruits are helped, five animals are beneficial, five vegetables are filled, and the smell is combined to serve it to supplement lean qi." Grain grain, as the "tower base" of the nutrition pyramid, occupies a very important position in the diet.
However, because grain grains are rich in nutrients, they are easy to grow insects if they are not well preserved. So why do grain grains grow worms? Can you still eat worms? How can I prevent worms? Here's one for you:
Common grains in supermarkets include rice, millet, glutinous rice, red rice, black rice, corn, oats, buckwheat, flour and other varieties. Among the common grain grains, rice and millet as raw material grain foods can generally be cooked and eaten directly; while processed grain grains such as wheat, corn and oats need to be ground into flour or rolled into slices for consumption.
In general, the grain products in supermarkets are mainly divided into packaging products and bulk products, of which packaged products are generally rarely worms in the shelf life due to pre-processing; the case of grain worms mainly appears in bulk grains and packaged grains after opening bags.
Why are grain grains susceptible to insects in summer?
Raw material type or processed type grain grain, once there are worm eggs, when the temperature and humidity reach a certain condition, the eggs will hatch into adults. There are generally three sources of eggs.
The first reason is that when the grain is still in the field, it has its own eggs with it. Although wheat, corn, and oats are processed, there are impact steps that can crush and kill the adult worms in the grain. However, some of the eggs they carry (mainly present in the embryonic part) do not die, and they will enter the finished product and hatch into larvae under suitable conditions.
The second reason is the presence of pests and eggs in granaries, feeding tools, equipment and means of transport. However, this probability is relatively small, because the cold chain is now mainly used for transportation, and under the action of low temperatures, the eggs are not easy to survive.
The third reason is that there may be insect sources in warehouses, supermarkets, kitchens and other environments, and some eggs are hidden in the bottom of rice tanks, rice bag seams, wall cracks, and ground cracks, and when the environment is suitable, the eggs will hatch into adult worms. If other food products in the supermarket are wormed, the adult worms may go to the neighboring grain house to "visit the door", resulting in the grain worm.
In the summer, due to the high temperature and humidity of the environment, the eggs dormant in the grain begin to stir, first hatching the "white and fat" larvae, after a long or short period of time, metamorphosis into adults, completing its life cycle.
Common grain grain insects include rice elephant and Indian grain borer, among which rice elephant mainly grows in granular grains such as rice and millet, while Indian grain borer is commonly found in various types of cereals.
Rice elephants, also known as weevils, belong to the Coleoptera weeminidae and are the main pests of stored grains. Adults are about the size of two sesame seeds, brownish-black, with a long, pointed beak, and six legs, commonly found in rice and legumes, and the larvae are off-white, about three to five millimeters long. Adults eat grains, and larvae eat inside grains. Harm rice, rice, wheat, corn, sorghum, etc. The life cycle of the rice elephant is about 20-50 days, the larvae hatch from mid-to-late June to early and mid-July, moth into the grain, the larval stage is about 30 days, the pupa pupae in mid-to-late July, the pupal period is 7-10 days, and the adult insects are feathered in early August.
Larvae and adults of rice elephants
There are two main types of flying insects produced in cereals such as flour, one is called Akatsuki, the larvae are cylindrical, and the adults are russet or brown, and the shell is hard. It is a coleoptera insect of the family Coleoptera, distributed in most provinces and regions of China, in the tropical and warmer regions of the world; its optimal development temperature is 27-30 °C; the relative humidity is 70%, 30 °C to complete the generation for about 27 days; the main harm to flour. The worm has odorous glands that secrete odorous liquid, which makes the flour have a musty smell, and its secretions also contain the carcinogen benzoquinone.
AdultSophics
The other is called the Indian valley borer, which is distributed all over the world, except for Tibet, which has not yet been found in China, and is distributed in other provinces, municipalities and autonomous regions. The larvae of the Indian valley borer are cylindrical in shape, and the adults have wings and can fly. Indian grain borer larvae like to eat grain embryos, often spit silk with grain grains and excrement, and knotted webs to seal its surface, so that it clumps deteriorate, sometimes we will find spider web-like objects in long-term storage of grain, that is, the "masterpiece" of the Indian grain borer.
Indian valley borer adult
Can the grain grain be eaten when it is wormed?
What if we find that the grain stored in our home has been wormed? Whether it can be eaten or not should be analyzed on a case-by-case basis.
Generally speaking, the insect body itself is harmless, and the insects can be eaten as long as they are not too serious. For example, rice elephants feed on rice and will not bite humans, so if there are not many insects, as long as they "sift through a sieve", or wash them clean, they can be eaten with confidence, and there is no need to throw away all the insects in a bag of rice, otherwise it will cause a lot of waste.
So is it harmful for larvae and invisible eggs to be eaten? Please rest assured, the larvae and eggs do not carry germs, there is no harm to the human body, if you accidentally eat it is not related.
But in some cases, grain and grain worms are a threat to human health. For example, adult worms gather together to produce a secretion of benzoquinone, which is carcinogenic, and if this adult worm appears in the grain, do not eat it. There are also Indian valley borers that spit silk, which is easy to make flour clumps and deteriorate, and if this adult worm appears in the flour, do not eat it.
In addition, after the grain grain is infected with insects, the original protective outer tissue is destroyed and susceptible to some plant pathogenic fungi, which tend to produce mycotoxins that are harmful to the human body, such as the infamous aflatoxin and the vomitoxin produced by Fusarium, which are far more threatening to human health than insects. Therefore, when encountering raw insect grain grain accompanied by clumps and mold, do not eat it again.
How to prevent the occurrence of grains in the household?
First, experts suggest that storage conditions should be improved, food containers kept clean, and the entry of pests from rice elephants and other storage pests should be prevented, thereby reducing the chance of insects. The means of preventing insects include the following:
(1) Grain storage tools should be clean and strict. It is best to put the grain into tanks, altars, and barrels, and have a tight lid. If you use a cloth bag, put a plastic bag on the outside of the cloth bag and tie the mouth of the bag tightly.
(2) Soak the cloth bag in boiled peppercorn water, then put the grain grain in the air-dried bag, and then wrap some new peppercorns with gauze, place them on the top, middle and bottom of the grain, and tie the mouth of the bag tightly. This is both mildew-proof and insect repellent.
(3) Mix kelp and rice in the proportion of weight 1:100, and remove kelp every week to dry off the moisture, which can keep the rice dry and not mildew, and can also kill rice worms.
(4) Put a few crab shells, turtle shells or green onions in the storage box, or sprinkle 1 inch of thick grass and wood ash, spread white paper or gauze, seal the container, and place it in a dry and cool place, which can also achieve the purpose of preventing insect moths.
(5) If the amount of preserved grain is small, it can also be protected by insect-proof packaging or adding long-acting odor repellent to the bag.
In addition, when the stored grain grain has been insect-like, but has not yet appeared in the case of agglomeration mold, the following means can be used to remove the insects:
(1) Sieve a sieve
When adult worms appear in grain grains, the most common method is "sifting through a screen". The grain of the insects is passed over, the worms are screened, the cleaned worms are burned by fire, and the containers containing the grain are cleaned, especially pay attention to the bugs in the gaps, and the hidden dangers should be eradicated.
(2) Freeze a freeze
Rice noodles that are placed for a longer period of time are most susceptible to insects in the summer, while the insect growth rate is lower in the winter. According to this situation, the remaining rice noodles stored after the winter are put into clean pockets and sent into the freezer of the refrigerator in stages and batches, so that they can experience the torture of 24-hour "cold winter". After such treatment, rice noodles are not easy to produce insects after the arrival of summer, probably rice worms and noodle insects cannot resist the coldness of "cold winter" and self-extinguish in "cold winter".
(3) Blow a blow
Place the cereal rice noodles in a cool and ventilated place, insert chopsticks into the rice noodles of the raw insects, and the insects in the depths of the rice noodles will crawl out of the warmer rice noodles. This method is simple and convenient, but the pest control time is longer. (Institute of Agricultural Product Quality Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Wang Gang, Gao Tao)