Bread gets stale, cream goes sour, fruit rots. But what happens to an unopened bar of chocolate left on a department store shelf?
In my personal experience it gets white flaky stuff all over it and smells, in a word, funky. Not safe for human consumption (as much as your really, really want to).
In my experience old chocolate gets a gray film on it and gets kind of dry and crunchy and well…not tasty anymore. But I’m speaking only of dark chocolate. I don’t eat the milk…
That is oxidation. It’s some of the fat in the chocolate extrudes out of the chocolate onto the surface. This leaves the chocolate with less fat, thus tasting ‘dryer’ and ‘stale’.
But it IS still safe for human consumption. All that’s happened is that some of the ingredients have ‘separated’ out onto the surface of the bar – it’s still the same ingredients as originally. Just like honey crystalizing if it’s left too long on the shelf. And, like that, if you melt either the honey or the chocolate, it will recombine into the original form.
It is quite true that oxodized chocolate does not taste nearly as good. But it’s perfectly safe to eat.
It becomes extremely dangerous and unstable. If you ever encounter a bar of chocolate that you even suspect may have reached its expiration date (ESPECIALLY high-quality dark chocolate), you should send it immediately to an expert trained in chocolate disposal. Email me for my mailing address.
At once! :eek:
So true! The EPA has been stockpiling expired chocolate that they can’t dispose of. Arizona won’t take it, New Mexico won’t take it. Nevada will take some of it because they can recycle it into casino chips.
Send it to Smithee. He’s the only one that can resolve this problem.
We send it to Hershey, who sell it to Americans.
Once upon a time I went to my ex-GF home for a visit, I boought a white chocolate bar on the way. I opened it and broke a piece of, some crumbs fell on my ex-GF lap, one was wiggling…
The worms where the exact same colour as the chocolate, by sheer chance we didn´t eat them. Then again I wouldn´t mind feeding maggots to her nowadays. 
I had the opportunity to witness just this very thing. It was on the set while filming the latest commercial. Mr. Yellow seized up and collapsed midscene and was immediately rushed to the hospital. Doctors pronounced time of death shortly thereafter. His friend and acting partner, Mr. Red was inconsolable. The body was laid out on the autopsy table. Subject’s white gloves and shoes were removed. Starting at the middle pillar of the lower-case ‘m’ emblazoned on the subject’s chest, an incision was made. It was discovered that underneath the sugar-shell epidermis, was a layer of chocolate and underneath that was, apparently a peanut.
Hmm. Your ideas are intriguing to me and I wish to subscribe to your newsletter.
Sounds like a build-up of cocoa butter around the heart. Occupational hazard, I’m afraid.
Or vice versa perhaps.
What kind of demented person lets chocolate expire?
Perhaps, but if you knew what the ingrateful bitch did to me you´d buy the maggots for me. 
If it’s been a member of the armed forces it gets a full military funeral.
21 gun salute, Marine Honour Guard, The Last Post played mournfully from a distant hill to echo across the valleys.
The coffin is normally draped with a new Snickers wrapper which is carefully folded after the ceremony and handed to the next of kin with a whispered word of condolence.
A civilian chocolate is usually just cast aside like a sodden glove, forgotten and mourned only by the person who bought it and so carelessly allowed to expire in an undignified manner.
Duh, it becomes ex-chocolate.
At the risk of being deemed a fuddie-duddie, I’ll return to the OP. The white flaky stuff is bloom. It’s the migration of cocoa butter to the surface. In and of itself, this doesn’t affect flavor, i.e., it’s just a cosmetic issue. But, with time, we can get a funky flavor which, as **t-bonhom ** notes, is oxidation, i.e., rancidity. Doesn’t make the chocolate unsafe, but does make it unpalatable. And I agree with Kat that it takes a certain kind of person to permit chocolate to hang around long enough to have this problem.
>>just a tiny hi-jack<<
Pal of mine, a postal worker, delivered mail to a house were the dog was forever lurking behind the mailbox waiting to bite his fingers. Asking the householders to restrain the dog didn’t work, they seemed to think it funny.
One day he bought a 1lb block of laxative chocolate and fed it through the mailbox one piece at a time, the result, I hear, was wall to wall shit, shit on the carpet, shit on the furniture…shit, shit everywhere
This is what the chocolate industry calls “bloom”. It’s a sign that it’s past its prime but certainly still edible.
A little further along, at room temperature, the fats will turn rancid, which makes it taste extremely nasty, though not unsafe AFAIK.