# Is It Safe To Eat Mouldy Bread? **URL:** \ **Category:** Factual Questions\ **Created:** [March 9, 2012, 7:52pm UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317 "2012-03-09T19:52:08Z")\ **Posts on this page:** 8\ **Page:** 3
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [March 14, 2012, 3:31am UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/41 "2012-03-14T03:31:56Z")
> [@constanze](#): > > We don’t eat any penicillium mold on cheese. We eat a very specific brand that’s introduced on purpose. I’m confused what you mean by this. Of course we eat penicillium in blue cheese, specifically P. roqueforti (among others), as your link says. Did you mean to say we don’t eat "penicillin,"or penicillium molds that produce penicillin like P. chrysogenum? ---
**Author:** ![WarmNPrickly](https://avatars.discourse-cdn.com/v4/letter/w/d78d45/32.png) [@WarmNPrickly](https://boards.straightdope.com/u/WarmNPrickly)\ **Post date:** [March 14, 2012, 3:41am UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/42 "2012-03-14T03:41:14Z")
> [@VOW](#): > > I repeat the comment I made upthread: If you are ALLERGIC to penicillin, you could have a reaction if you eat mold, specifically, the penicillium mold. > ~VOW I’d be suprised if there were enough penicillin in slightly moldy bread to produce any serious allergic reaction in even severely allergic people, but I’ve been wrong before. Can you demonstrate that this happens? I think eating slightly moldy bread is fairly common, so I don’t think these cases should be rare. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [March 14, 2012, 3:52am UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/43 "2012-03-14T03:52:24Z")
> [@WarmNPrickly](#): > > I’d be suprised if there were enough penicillin in slightly moldy bread to produce any serious allergic reaction in even severely allergic people, but I’ve been wrong before. Can you demonstrate that this happens? I think eating slightly moldy bread is fairly common, so I don’t think these cases should be rare. This isn’t a medical citation, so take it with a grain of salt, but [this person thinks he had an anaphylactic reaction](http://www.experienceproject.com/stories/Had-A-Near-Death-Experience/756467) to bread mold. ---
**Author:** ![WarmNPrickly](https://avatars.discourse-cdn.com/v4/letter/w/d78d45/32.png) [@WarmNPrickly](https://boards.straightdope.com/u/WarmNPrickly)\ **Post date:** [March 14, 2012, 4:16am UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/44 "2012-03-14T04:16:06Z")
If what he says is true, then he certainly severely allergic. I doubt that it is the first time he’s eaten moldy bread, but that’s how allergies sometimes work. Clearly he is no stranger to allergies, since he had an epi pen. If the mold is genuinely what he reacted to, then mold is dangerous to severely allergic people. I think eating slightly moldy bread is a lot more common though. As has been pointed out, by the time it actually looks moldy, there is mold all over. I don’t think most people throw out bread that quickly. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [March 14, 2012, 3:30pm UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/45 "2012-03-14T15:30:59Z")
> [@pulykamell](#): > > …Most of your fermentation is due to what is already in the flour. > > You can read my method to [Polish sour soup here.](http://www.lthforum.com/bb/viewtopic.php?p=221326) (My name is “Binko” on that board.) As I state in there: "My father claims that żurek is always made on rye flour, while biały barszcz is made on whole wheat flour. > > ETA: I should add, that in that recipe I did use a little bit of a healthy sourdough starter to get things moving a little bit longer . .. I live in a Polish neighborhood, and a deli/store sells bottled zhur. How the hell do they stop the fermenting? I believe w/ wine they zap it with alcohol at a certain time… ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [March 14, 2012, 3:46pm UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/46 "2012-03-14T15:46:40Z")
> [@Leo\_Bloom](#): > > I live in a Polish neighborhood, and a deli/store sells bottled zhur. > > How the hell do they stop the fermenting? I believe w/ wine they zap it with alcohol at a certain time… Well, eventually the microorganisms run out of food, so their fermentation stops naturally. With stuff like beer and wine, you usually just let it ferment until there’s no longer any sugars left to ferment. You don’t have to do anything special, and you can buy certain beers that still have live yeast in them (like many Belgian beers and some domestic ones like Sierra Nevada.) If you want to add sweetness, you usually first have to “stabilize” the wine with potassium sorbate to kill the yeast, and then you add sugar. Or you can filter out the yeast. I’m not sure what they do for commercial żur. I would just assume either that it’s pasteurized (treated with heat to kill the microorganisms) or just fermented to the point that it can’t ferment any more. I just checked the ingredients on a bottle of żur I have in the fridge, and it’s only rye flour, garlic, and water, so it doesn’t appear to be chemically stabilized. ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [March 14, 2012, 3:52pm UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/47 "2012-03-14T15:52:24Z")
> [@Cheshire\_Human](#): > > Pretty close, except there was one more step 1a) Don’t grind up the bread. Identify the penicillin mold on the bread, draw a sharp knife through it, then lightly slice the skin of an unpeeled orange with it. The mold then grows in the orange skin, without other species interfering, and liquid oozes out of the cut after a couple of days. The liquid is much richer in penicillin than the original bread. Proceed with step two using that. As has been mentioned in passing upthread, orange oil (derived from the peel) is hella anti-microbial. You can buy expensive little bottles of it to dilute as a cleaner and as a gardening aid. I’d think the oil would both kill the mold AND be the source of the oozing. > [@RealityChuck](#): > > In general, if you can see it or smell it, it probably won’t make you sick. That’s just basic evolution: an organism that needs to reproduce in your body won’t warn you away, and one that can’t get by your gastric juices will in order to keep from being destroyed. OK. I’ll leave this gorgeous fresh ribeye steak out on the counter for a couple of days. Once it smells horrific, you can eat it. Same with this here glass of milk, and that tuna salad sandwich. I mean, sure, they stink to high heaven and are covered with all manner of colorful growths. So, by your logic, they’re fine! Enjoy! ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [March 14, 2012, 4:49pm UTC](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317/48 "2012-03-14T16:49:03Z")
> [@RealityChuck](#): > > In general, if you can see it or smell it, it probably won’t make you sick. That’s just basic evolution: an organism that needs to reproduce in your body won’t warn you away, and one that can’t get by your gastric juices will in order to keep from being destroyed. What’s also basic evolution is that your sense of taste causes you to be revolted by things that are not good to eat, otherwise there would be no reason for you to evolve a sense of taste. :smack: :smack: :smack: [Previous page](https://boards.straightdope.com/t/is-it-safe-to-eat-mouldy-bread/615317.md?page=2)