Mrs. Wages makes several packaged mixes to help make home canning easy and quick. All of their products for canning use the water bath canning method. But do the mixes have a shelf life?
The company recommends using their mixes within 24 months of the day and year it was produced. On the side of every package is an 8 digit code. On the packets, it is imprinted on the package. On the salsa canisters, it is printed on the bottom. So, in the example at right, the B identifies the production facility. The 5 is the last digit of the year the mix was produced (2015). The next three numbers indicate the day, out of 365 days in the year, the mix was produced. So 138 is May 18. This is known as the Julian date. The last three digits indicate the production batch code, B92. So this particular mix has expired and should not be used.
Source: www.mrswages.com/canning/frequently-asked-questions/