1。 First of all, for coffee lovers who buy raw coffee beans and bake them themselves, raw coffee beans do not have a certain shelf life. As long as it is kept at the right temperature and humidity, it will not go moldy and deteriorate. Even if it is stored for decades, there is still no big problem. Some raw beans will be specially stored to make them "aged", so that the taste will become softer. 2。 For most people, we buy roasted coffee beans, which are called cooked beans. Generally, the production date and shelf life of prepackaged coffee beans will be indicated on the packaging bag, and the shelf life varies from 1-2 years. This is a label made by merchants out of caution. In fact, as long as it is properly preserved, expired coffee beans will not bring any obvious consequences and will not affect health except that the taste may be slightly worse. 3。 However, this does not mean that the flavor of coffee beans will remain unchanged. Coffee beans taste best in the first few weeks after roasting. It can also be understood that the best tasting period of coffee beans is 1-2 months. As time goes on, the aromatic substances that make up the flavor of coffee beans will gradually evaporate and disappear. At the same time, coffee beans gradually "age" under the action of oxidation and moisture, which may produce bad flavor. Because deep roasted coffee beans have many and large pores, oxygen and moisture can easily penetrate into them, so the deeper roasted coffee beans are, the faster the aging rate will be. 4。 Air, light and water will accelerate the aging of coffee beans. Therefore, when storing coffee beans, you must choose a well-sealed container to isolate air and moisture, avoid oxidation and moisture, and place it in a low temperature and dark place. You can choose a special coffee bean container, and an idle thermos cup is also a good choice. Glass containers need to be protected from light.