HI fellow bakers, I am hoping someone would be able to assist me with what can be added to my cookie dough so that they will have a longer shelf life once they have been packaged and sealed, for retail sales. and where I might find the additive. It is also important to note that I live in a tropical climate should this impact your advice or suggestions.

sodium propionate inhibits mold growth. use 0.1 to 0.3 percent of flour weight.