I make and sell a very good salsa. I do not use any preservatives however I do use lime juice for flavor but I have found out that it is also a preservative because of the citric acid. I am currently using about 3 oz of lime juice per 4 pounds and it keeps for about 3 weeks.How much lime juice per pound should I use. Is 3 enough or should I use a little more Also, does the acid in the tomatoes help preserve it as well. Thanks