I have some recipes from my grandma, that do not have how long they are good for....
Is there some way to figure this out?
Here is one
1 white potato (cooked and mashed)
7 cups of powdered sugar
1 tsp mint flavor
Mix, and dip in chocolate
I am no way a food scientist, but I wouldn't eat mashed potato after it had been in my fridge for around 3 days, for example. I know it is mixed with a lot of PS, which is a preservative, and covered in chocolate so it will be airtight, but even so...I would still say around 2-3 days?
More potato candy recipes:
(With tips on storage.)
http://bigspud.com/files/pcandy.htm
http://allrecipes.com//Recipe/pioneer-potato-candy-2/Detail.aspx
HTH
Potatoes will start to ferment after a while, there's a type of sourdough that's made with mashed potatoes. (I think I'll make some today, thanks for the reminder, haha!) 2-3 days in the fridge sounds about right.
oh really?
I have made this recipe before, and it has lasted 2 weeks, before they were all gone......
hmmmm, well thanks for that 
But I wasnt just talking about this recipe, Is there anyway as a baker/confectioner, to figure out the expiration dates of a recipe
Hahaha, what, they didn't turn to sourdough? Haha!
Here's a chart that mostly explains what the sell-by date means, but on the sidebar on the right side of the page it has a chart of different types of food and how long they should last. http://www.gourmetsleuth.com/Articles/Nutrition-Health-Food-Labeling-646/food-expiration-dates.aspx#r1
I don't think that's exactly what you're looking for, but it's the closest thing I could find, everything else just looks like it has individual ingredients listed.
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