A change to the sell-by dates on food

Re:A change to the sell-by dates on food by ridgeguy on Thursday February 16, 2017 @08:26PM (#13665181)

Aspirin is acetylsalicylic acid. When it's exposed to water vapor, the acetyl group comes off and combines with water to make acetic acid, which is the acid in vinegar [1].

This happens pretty fast. An open bottle of uncoated aspirin tablets can start to smell of vinegar in a day or two, depending on the local relative humidity.

If you smell vinegar when you sniff your bottle of aspirin, toss the bottle. Why? Well, the other hydrolysis reaction product (salicylic acid) removes the outer layer of the skin and is used, for example, to remove warts [2]. Not something you want in your stomach.

[1] http://www.kii3.ntf.uni-lj.si/analchemvoc2/file.php/1/HTML/S...

[2] https://en.wikipedia.org/wiki/Salicylic_acid

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Re:A change to the sell-by dates on food by ItsDeathball on Thursday February 16, 2017 @08:41PM (#13665254)

I had always wondered why aspirin tended to smell like vinegar and rarely helped with headaches. It's quite satisfying to have an explanation for both.

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Re:A change to the sell-by dates on food by Symbiote on Friday February 17, 2017 @02:36AM (#13666625)

In general, expired or unwanted medicine should be taken to a pharmacy or similar for proper disposal.

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Re:A change to the sell-by dates on food by tossaway1 on Thursday February 16, 2017 @08:30PM (#13665206)

Isn't your stomach already extremely acidic...?

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Re:A change to the sell-by dates on food by enknamel on Thursday February 16, 2017 @09:02PM (#13665345)

Not all acids are the same. What's at play isn't only the amount of free protons but also what else is disassociating. For instance, hydrofluoric acid is considered a weak acid but it can severely burn (pretty slowly but it will get you) or even kill you. The fluoride group will consume the calcium ions in your blood and possibly send you into cardiac arrest.

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Re:A change to the sell-by dates on food by rcthompson on Thursday February 16, 2017 @11:14PM (#13665866)

Any compound with a hydrogen ion that can dissociate in solution is technically called an acid, but that doesn't mean it's acidic properties are the most relevant.

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Re:A change to the sell-by dates on food by mmmpop on Thursday February 16, 2017 @09:15PM (#13665415)

Thanks, this is a great comment.

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Re:A change to the sell-by dates on food by skookumchuck on Thursday February 16, 2017 @09:51PM (#13665570)

Sounds like a good argument for coating the pills.

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