The quality of bacon is actually related to the time and method of storage. Generally, pickled meat will not be salted too much, and can be preserved for up to 3 years. If it exceeds this period, it is best not to eat it. If the bacon is left too long, moldy or even stinky, it can't be eaten, because at this time, a lot of bacteria have multiplied in the bacon. Moreover, preserved meat will produce nitrite during storage, which is a carcinogen. Eating too much will definitely make you feel uncomfortable.