One is to look at the packaging, look at the label
　　 First observe whether the outer packaging is neat and clean, whether the handwriting is clearly printed, and whether the label is complete and regular. The labels of canned food produced by regular manufacturers are complete and clear. The brands recommended by the China Canned Food Industry Association such as Zhejiang Huangyan No. 1 Canned Food Factory (enterprise code L51) are first-class in quality. The factory code of the cannery consists of an English capital letter plus Arabic numerals within 100, which is printed on the can lid or bottom. Those with such codes indicate that a series of indicators such as the production technical conditions and product quality of the manufacturer have passed the audit of the China Canned Food Industry Association, and the quality is guaranteed. It should also be marked with product name, factory name, factory address, ingredient list, net content, solid content, implementation standard code, quality level, and shelf life; if the bottle printing quality is found to be poor, the handwriting is illegible, and the content of the label is incomplete, it is likely to be The quality of counterfeit products is difficult to guarantee. Second, determine whether the product is within the warranty period.
　　 The second is to check the internal quality and evaluate the senses
　　 For products packaged in glass bottles, the color, state, and smell of the contents can be checked, and the block shape of the contents can be observed to see if there is no foreign matter or turbidity. The contents of good-quality cans are natural and fresh color inherent to raw foods, and the block shape and size are basically the same, and they are complete and not loose. When buying canned fruits, the color of the fruit should not be browned. The sugar water is clear and transparent. Except for the slight sedimentation of pulp debris, there is no impurities, no suspended matter, or turbidity; the smell is pure, the taste is normal, and there is no abnormal color. Peculiar smell. For products packaged in metal cans, the surface should be clean and free of rust, the bottom and cover should be slightly recessed, the welds and bottom curling should not be damaged, and the door should be tightly sealed without deformation. If you find rust on the inner and outer walls or lid of the metal can due to corrosion, please do not buy or eat it.
　　 The third is to prevent "fat listening" and miss listening
　　 Fat and missed sounds are important external characteristics of canned food deterioration. When the canned fruit is contaminated by microorganisms and loses its edible value, it often produces a "fat sound" phenomenon. The iron center of the bottom and lid of the normal can is flat or slightly concave without leakage. The phenomenon of obesity is the bulging of the tin center of the bottom and lid of the can. The reason is that the bacteria in the can multiply and produce gas, and the pressure in the can is greater than the air pressure. Leakage refers to cans with leaking seals. During transportation, products packed in metal cans are collided by objects, and the outer wall often sinks. Air is easy to enter, causing the contents to become rancid and deteriorate. It is found that the above-mentioned products cannot be eaten. The following methods can be used to check fat and missed hearing: First, see if the bottom and lid of the can are raised, and if there is any liquid flowing out. The second is to tap the bottom and lid with the knuckles of the fingers. The quality of the voice is clear and normal, and the voice is muddy and hoarse, which is fat or missed. The third is to squeeze the lid and bottom of the can. If the liquid overflows or cannot be restored to its original state after squeezing, it means that it is a leak. For products packaged in glass bottles, normal products have a certain degree of vacuum, and there is a crisp sound when knocking on the bottle cap. If there is no vacuum, the product is more likely to have quality problems.
　　Fourth is to choose genuine products.
　　 Consumers should try their best to buy products produced by formal enterprises or those with a certain scale in the main product production areas in reputable shopping malls. When purchasing, you should carefully check the production date, shelf life, and carefully check the integrity of the outer packaging. When buying canned fruit, distinguish between canned syrup and canned syrup. The concentration of canned syrup is generally around 15%, which is more suitable for direct consumption. Canned syrup has a high concentration of sugar water, above 65%, which is only suitable for food processing. Therefore, consumers should clearly see the concentration of sugar and water on the food label when buying, and then make a distinction before buying.
Fifth, it should be eaten early.
　　 After the canned food is opened, it is easy to cause a large number of microorganisms to multiply, cause the product to deteriorate and lose its edible value. It is recommended that consumers try to eat them all at once to prevent spoilage and food poisoning.