# Butter accidentally left out overnight. Will it kill me?

**URL:** <https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728>\
**Category:** Cafe Society\
**Created:** [August 27, 2010, 10:41pm UTC](https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728 "2010-08-27T22:41:27Z")\
**Posts on this page:** 3\
**Page:** 3

<div class="post-metadata">

**Author:** ![Norse](https://avatars.discourse-cdn.com/v4/letter/n/a9adbd/32.png) [@Norse](https://boards.straightdope.com/u/Norse)\
**Post date:** [November 23, 2010, 7:23am UTC](https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728/41 "2010-11-23T07:23:13Z")

</div>

> [@PunditLisa](#):
>
> Remember that neither milk nor eggs came out of their respective hosts chilled to 55 degrees.

But while eggs are still neatly packaged in an aseptic packaging even after coming out of their host, milk is not. So, milk (being a very good bacterial medium containing sugar, protein, vitamins and trace elements) can very well spoil by being left on the counter overnight. Been there, done that. OTOH, spoiled milk is easy to identify, and a quick sniff or a quick tasting will easily tell you if the milk is safe to drink. Butter doesn’t spoil easily, there’s just not enough water there to allow much microbial growth. Given time, butter turns rancid by oxidation, but rancid butter is also pretty easy to identify. You don’t want to eat that.

Side note: In the old days, milk was not pasteurized and would turn sour due to the natural lactic acid bacteria. We even soured milk to keep it for a long time and drank it without any problems. Modern industrial (pasteurized) milk turns rotten and downright nasty. Also, in the old days, people did get sick from eating or drinking spoiled foodstuffs. That’s why Louis Pasteur advocated the pasteurization of milk.

---

<div class="post-metadata">

**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\
**Post date:** [November 23, 2010, 8:31am UTC](https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728/42 "2010-11-23T08:31:23Z")

</div>

In general, even spoiled pasteurized milk isn’t that unsafe. I know people who like their milk a little chunky.

And I do keep butter in the fridge, just like I keep almost anything else that is opened and wet (besides water). That doesn’t mean I get a stick out a few hours ahead of time so it will be easy to spread. Or, when I have more money, just get spreadable butter.

---

<div class="post-metadata">

**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\
**Post date:** [November 24, 2010, 1:33pm UTC](https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728/43 "2010-11-24T13:33:22Z")

</div>

> [@Saltire](#):
>
> Can’t seem to google up the right reference, but I recall back in the '70s or 80s archaeologists found a large ball of butter that had been stored in an Irish peat bog around the time of the construction of the pyramids of Egypt. One of them ate some and said it tasted a bit funny, but caused no ill effects. In the right conditions, the stuff is durable.

I have heard about this so-called “bog butter”-is it common? Human bodies left in bogs are well preserved, so I suppose that butter would be no problem.

[Previous page](https://boards.straightdope.com/t/butter-accidentally-left-out-overnight-will-it-kill-me/551728.md?page=2)