Evaporation… the taffy will dry out and become hard and unworkable. It’s horrible.
ps- Here’s a Bonus tune:
Almost, but not quite. The top selling candy bars all contain chocolate, but there are a few non-chocolate candy bars-- PayDay and other peanut nougat logs, Snickers Munch and other peanut bars, Zero, Zagnut, Abba Zabba and Big Hunk (for those lucky enough to get Annabelle brands), Hershey Cookies & Creme, etc.
When I served in Vietnam, we were often sent chocolate candy by stateside relatives. The jungle environment caused much to have a white coating by the time we received it. We were told it was harmless, and we ate it all without suffering any ill effects that I know of, but the chocolate sold on base or locally was formulated for tropical environments and didn’t have that problem.
Now other candies often absorb moisture, even if wrapped. No harm is done AFAIK except it makes it hard to unwrap sometimes.
There’s nothing magical about cocoa butter. Cocoa butter and other hard fats seldom turn rancid because they’re saturated; it’s unsaturated fats that have this weakness, as the double bond in such fats is subject to oxidative attack, producing short-chained aldehydes and ketones, which smell bad and taste worse. The increasing use of hydrogenated vegetable oil in milk chocolate has led to a decrease in shelf life (and frankly, it’s not so great when it’s fresh). I assume the milk solids in milk chocolate also have some longevity issues, but I haven’t really looked at that.
The white “bloom” on chocolate that been exposed to heat is, as others have said, just migration of the fat to the surface, and indicates neither rancidity nor any other spoilage (though exposure to heat may also cause these problems).
My question would be, if you’ve grown up accustomed to Hershey’s, would you even be able to tell if a chocolate bar had gone rancid? 
True dat. Hershey’s is nasty.
You got us, Mr. British person. You got us. Zing!
Just to dump on Hershey a bit myself, many of their products lack cocoa butter and so presumably wouldn’t bloom as they age, like proper chocolate does. (They might deteriorate in other visible ways though.)
On the other hand, Hershey isn’t the only brand of chocolate available here, you know. Nor is it the only US chocolate company.
So there.
Yes, if let in a hot environment, chocolate will begin to melt during the hot day, hardens again when the temperature gets lower,etc..After some days, it will have turned “white”. Probably what happened to the chocolate sent to Vietnam mentioned above.
I know you’re just playing, but there is a lot worse chocolate that Hershey’s. I’d consider Hershey’s the middle class of chocolates that I’ve tasted.
Well, since bloom is just fat separating, like cream rising to the top of your milk, I’d imagine that chocolate will show bloom even is some other fat was used in it.
I dug into a bag of Reese’s cups that had been sitting in my pantry since last Xmas. After downing a half dozen or so, I stopped when I found out that I was not alone in enjoying them, that I had been sharing my meal with some moth larvae. If not for that, I probably would have finished the bag. Ironically, they were probably the most nutritious thing in the bag.
Indeed. The chocolates that don’t bloom, the ones that are formulated for hot weather (as noted above), incorporate harder fats (like carnauba wax, maybe?) or paraffin wax. Hydrogenated vegetable oil or other cocoa butter substitutes will migrate in hot weather, although the result may not look exactly like the cocoa butter bloom.
My mom buys all of her candy canes right after Christmas when they go on sale, and then lets them age for at least a year before eating them, because she prefers them that way. There are probably some candy canes around her house that are five or more years old. They’re different than fresh ones, certainly, and you might prefer them fresh, but they’re not harmful.
There aren’t many chocolates that have the distinctive spoiled flavor of Hershey.
Many long years ago, on my first ever trip, I thought a dollop of butter at Village Inn was ice cream for my blueberry waffle. I was 8. Every adult at the table howled with laughter.
Don’t forget Air Heads!
And Bonomo’s Turkish Taffy!
(yes, it’s back! Just like 1960!)
Licorice and the various red things (by American Licorice - good stuff)
Twizzlers (which look and feel like vinyl - I am not sticking that in my mouth)
Watch out I’ve been called a snob here for saying Hershey’s sucks compared to most of the popular EU brands.
But god it does.
I’ll throw caution to the winds and repeat my sentiment. Hershey’s is, hands down, the worst commonly available chocolate. The … fucking … worst.
Seriously. Hershey can go eat a dick.
Assholes.