I am a cupcake & muffines industry owner in Iran. I have problem about taste of cake after pass a month from the life of cakes. Our products have 3 months life time . It seems after pass the one month the our cake has drug ( pharmacy ) taste but i don’t what is the problem? our products composition are : Flour, sugar, new egg, baking powder, emusifier gel ( mono & di glyseride ), expander life ( propylen Glycole, Sorbitol , mono & di glyseride ), flavers.
Thanks

Welcome to the board. If the cupcakes and muffins don’t taste good after 1 month, then it would seem that the life span of your products is really 1 month, not 3 months.

Most of us on this board don’t use preservatives in our baked goods. We create them so that they can be consumed within a few days of baking. So, you might want to look on Google for boards that are targeted toward trade professionals like yourself who want a very long shelf life for their products. Good luck!

How are you storing your product?  Is it indivdually wrapped?  Refrigerated?  Even with the added preservatives, your shelf life is really only about a week in a refrigerated environment.
If you are looking for a longer shelf life, you should be freezing the product as you make it; then rotating your inventory.  I agree with the other response that you should be working on a shorter production schedule.