怎样挑选食品罐头1.挑选离出厂日期近的。罐头食品在正常情况下,一般能保存一年半至二年时间。2.观察罐头外形。正常的罐头底盖中心部分略凹,如果底盖两头鼓起,这大多是由于罐内杀菌不严,由微生物引起食物腐败变质造成的,不宜购买。3.听罐头声音。用手指敲击底盖时,声音清脆的是好的,声音浑浊的则密封不严,真空度不大。食物可能已变质。4.观看颜色。玻璃瓶装的果蔬 How to choose food cans 1. Pick from the date of manufacture near. Canned food under normal circumstances, can generally save a year and a half to two years. 2. Observe the shape of the can. The normal central part of the can bottom slightly concave, if the bottom cover two bulges, which are mostly due to the tank lax germ caused by microbial spoilage caused by the food should not be purchased. Listen to canned sounds. When you tap the bottom cover with your fingers, the sound is crisp and the sound is cloudy and the seal is tight and the vacuum is low. Food may have deteriorated. 4. Watch the color. Glass bottles of fruits and vegetables