Ask for biological experiment report, grade one.

1. Pepper pest control method: Pepper is a natural antioxidant with a special smell. Boil pepper water in a pot, soak the bag in it after cooling, take it out to dry, pour the dried rice into the treated bag, wrap some peppers with gauze, put them in various parts of the rice, and put them in a cool and ventilated place after bagging.

2. Anti-mildew and insecticidal method of kelp: dried kelp has strong moisture absorption ability and also has the function of inhibiting mildew and killing insects. Mix kelp and rice according to the weight ratio of 1: 100. After one week, take out kelp and dry it in the sun, and then put it back in the rice bag, so that the rice can be dried, which has the effect of mildew prevention and insect prevention.

3. plant ash moisture absorption method: Sprinkle plant ash with a thickness of about one inch on the bottom of the rice jar, spread white paper or gauze, then pour in the sun-dried rice, seal it and put it in a dry and cool place, so that the treated rice can be preserved for a long time.

If the rice stored at home is a bug, it can be screened out with a sieve, or it can be dried in a cool and ventilated place. Never expose the rice with insects to the sun, because this will not only make the insects afraid of light enter the rice layer, but also make the rice grains quickly dehydrate and become rough and broken, which will not play an insect-proof role at all. The screened rice should be packed in reasonable bags, preferably cloth bags, not woven or gunny bags, not to mention plastic bags. Old cloth bags should be cleaned before use to prevent eggs from attaching. After the rice is bagged, put a small bag of pepper wrapped in cloth and several cloves of garlic at the seal, and tie the bag tightly with a string until it is opened when eating.

The rice bag is stored in a ventilated and dry place, padded with bricks or boards, and kept at a certain distance from the ground to improve ventilation.

2. 1. Put the rice in a clean container, and put100-200g of white wine in a wine bottle. The opening is buried in rice, and the bottle mouth is slightly higher than the rice surface. Seal the window in case the rice is infected. Remember that the container mouth must be sealed.

2. Divide 25-50g of Zanthoxylum bungeanum into 4-6 parts, wrap it with small gauze and put it in the middle and four corners of rice barrel or rice vat, so that rice will not breed.

Three, put some quicklime (ash) or plant ash at the bottom of the rice jar, spread plastic sheets, and then pour the rice. Or put some garlic cloves in the rice to prevent insects.

Fourthly, the dried kelp can be put into a rice jar (the brick in the jar is moisture-proof), which can kill insects and mold. The method is to put about 1 kg of dried kelp into 100 kg of rice. After 7 days, it can kill more than 96% acaroid mites and moth pests and absorb 3% rice moisture. After kelp is dried in the sun for a short period of time, the absorbed water can be discharged and then put into a rice jar, which can still be used. This method is non-toxic, harmless, cheap and fast, and is also suitable for insect control of other grains.

Kelp can prevent rice from becoming moldy. Adding 100 kg of kelp into 1 00 kg of rice can kill pests and inhibit mold. However, kelp should be taken out every 10 days or so, and put into rice after 10 minutes. One serving of kelp can be reused for more than 20 times.

3. Agricultural and sideline products are the necessities of human survival. The research on the fresh-keeping packaging technology of agricultural and sideline products has become a research hotspot in many countries, and new achievements in the research of fresh-keeping packaging technology of agricultural and sideline products abroad have emerged one after another.

New technology of grain preservation

Bulgarian agricultural experts invented a simple and economical new method to preserve grain. When the crops are harvested, dry the seeds a little, put them in a big polyethylene bag and seal them. The grain preserved in this way will neither volatilize water nor become moldy, and can be preserved until the next spring, and the nutritional content of the grain will not be reduced at all.

Rice fresh-keeping packaging bag

A Japanese company has introduced a kind of packing bag with strong sealing performance. This kind of packing bag is made of a kind of plastic called "Chikelon", which has excellent oxygen isolation effect. When it is used to package new rice, the fresh-keeping effect is particularly good, and the color, fragrance and taste of rice can be kept unchanged for a long time. The carbon dioxide produced in the bag also has the functions of preventing insects and mildew.

4. 1. Storage characteristics of rice

Rice is a finished grain, which loses its protective layer after processing, so its storage stability is poor. Its characteristics are: 1. It absorbs moisture easily. Because the endosperm of rice is directly exposed, hydrocolloids such as starch and protein are in direct contact with air, which is easy to absorb water; In addition, rice is often mixed with a certain amount of rice bran, and rice sugar contains more fat and is easy to absorb water. The moisture content of rice increases after moisture absorption, which provides favorable conditions for mold growth and easily causes mildew and fever. 2. It is easy to burst, that is, cracks appear on the rice grains. Dispelling moisture, absorbing moisture too fast and high temperature are all easy to cause waist explosion. The rice after waist explosion is fragile, and mold is easy to grow on the broken rice, which leads to mildew and deterioration.

Second, the mildew-proof methods of rice in summer

In order to prevent rice from mildew and make it spend the summer safely, dry, low temperature and closed storage methods are mainly adopted. Hot rice should be cooled, removed by air screen and packaged or stored in bulk. Specifically, the following methods can be adopted:

1. Store regularly and strictly control humidity.

The water content of conventional stored rice should be controlled below 13%~ 13.5%, and it should not be increased during storage to ensure the safety of rice in summer.

2. Low temperature storage. If the temperature of rice is kept at 15℃ ~ 10℃, it can not only maintain the good quality of rice, but also prevent mildew. It usually includes natural low temperature, mechanical ventilation, mechanical refrigeration and air conditioning low temperature.

The storage cost of natural low-temperature storage rice is low, but it is limited by climatic conditions. In the northern region, ventilation can be used to cool down, and then sealed to keep warm.

Using mechanical ventilation combined with refrigerator to reduce the temperature of rice and realize low-temperature storage is a method with less investment, low cost and good fresh-keeping and mildew-proof effects. First, we should do a good job in heat insulation and moisture prevention of granaries. Secondly, in hot summer, mechanical ventilation should be used at night when the temperature of grain is low, so when the grain temperature drops to near temperature and cannot continue to drop, it should be refrigerated in the refrigerator, and cold air should be blown into the grain pile to make the grain temperature drop below 15℃ as soon as possible, and then the grain surface should be covered and stored in a sealed way.

3. Modified atmosphere storage, including natural hypoxia, carbon dioxide filling, nitrogen filling and other methods. Generally, the grain pile is sealed with plastic film or other airtight materials to change the gas composition in the grain pile, so that the grain pile is in a state of low oxygen, high nitrogen and high carbon dioxide, and the purpose of mildew prevention, insect killing and safe summer escape is achieved.

The natural anoxic storage cost of rice is low, and it does not need mechanical equipment, but it has an impact on the quality of rice, especially for rice with high moisture content, which will reduce viscosity and increase fatty acid value. If the anoxic grain pile is filled with carbon dioxide, the effect of preservation and mildew prevention is very good. According to the test, small packaged rice can be safely stored for 2 years at 0 ~ 35℃ when stored with carbon dioxide.

Compared with carbon dioxide grain storage, nitrogen-filled grain storage can reduce the cost and have good storage effect. A practical method is to use molecular sieve nitrogen-enriched machine for negative pressure cyclic replacement. The closed grain pile can be filled with nitrogen for 4 hours, which can remove oxygen and moisture in the grain pile. When the nitrogen concentration reaches about 99%, the mold inhibition effect is remarkable.

4. "Double Low" storage. On the basis of anoxic storage, using low-dose phosphine to keep rice fresh, especially for high-moisture rice, has better mildew-proof effect and can ensure the safety of rice in summer. Fresh keeping of high moisture rice in summer is a common method in cities at present. Usually, aluminum phosphide tablets are wrapped in small cloth bags, and slowly released and fumigated in the depth of the grain pile through probe management, and the grain pile is sealed, so that the oxygen in the grain pile is not higher than 12% and the carbon dioxide is about 8%. The application of 10 ~ 20g per 5000 kg of rice can obtain good mildew-proof effect.

5.① Divide 25-50g Zanthoxylum bungeanum into 4-6 parts, put them in small gauze bags, and put them in the middle and four corners of rice barrel or rice vat respectively, so that rice will not be eaten by insects.

(2) Poke out the bone marrow in the turtle shell with fine wire, then wash it with hot water, dry it and put it in a rice jar to prevent rice moths and moths.

6. Putting crab shells in rice can prevent insects.

The crab shell is placed in the rice barn because there is a substance called chitin in its shell, which can effectively control the growth of mold. Chitin is not unique to crabs. Chitin exists in crustaceans, insect shells, fungal cell walls and some green algae. Chitin has a wide range of uses: it can be used to make polishing agents, fillers and emulsifiers in industry; In agriculture, if plant seeds are wrapped with chitin, it can prevent fungi from invading, thus improving the disease resistance of plants; Chitosan can also be used for the synthesis of medical polymer materials and the preservation of food.

If garlic or pepper is used to repel insects, it has a special smell, just like the principle of moth balls.