Can I use this Half-and-Half?

November 27, 2017 1:17 AM

I thought I put away the ultra-pasteurized half and half in the fridge when I got home from the store yesterday afternoon (about 14 hours ago). Alas, I did not. It’s ultra-pasteurized; it’s unopened: can I still use it? My 4AM coffee-needing self thanks you.
posted by ocherdraco to Food & Drink (11 answers total)

According to Wikipedia, UHT milk has an unrefrigerated shelf life measured in months.

Has it been more than a month since you got home from the store yesterday?
posted by yohko at 1:22 AM on November 27, 2017 [4 favorites]

Or if it's HTST milk that only stays good for two weeks out of the fridge.
posted by yohko at 1:23 AM on November 27, 2017

I'd use it! That stuff doesn't spoil easily.
posted by quince at 1:26 AM on November 27, 2017 [1 favorite]

Yeah, fine.
posted by pompomtom at 1:59 AM on November 27, 2017

Response by poster: Yay! Forgive my lack of googling; I’m a medical student on my surgery rotation heading into the hospital to see patients before rounds. I’m very glad to know that I’ll be able to use it.
posted by ocherdraco at 2:08 AM on November 27, 2017 [2 favorites]

Once you open it, it will spoil if left un-refrigerated, but yeah, here we call it 'long life milk'. I like to keep some in the pantry in case of "argh I thought *you* were buying milk" emergencies.
posted by freethefeet at 3:17 AM on November 27, 2017 [1 favorite]

Ultra-pasteurized is not the same as UHT milk (or HTST for that matter). UHT is not even stored in a refrigerated case to begin with. Ultra-pasteurized is what almost all milk is in the US, and UHT milk is absolutely not common here in my experience (as opposed to Europe, where it's all over the place.) You're still probably fine drinking it, but that stuff is supposed to remain refrigerated at all times.
posted by thegreatfleecircus at 6:31 AM on November 27, 2017

Ultra-pasteurized is not the same as UHT milk

Isn't it? They're both flash heated to the same temperature for the same amount of time and the terms seem to be used interchangeably. The only difference I can find is a mention of aseptic packaging for UHT milk specifically sold as shelf stable (PDF). It looks a whole lot like the only reason the product is labeled "Ultra-Pasteurized" and sold in the fridge (and not UHT on a shelf) is just to get past American qualms about unrefrigerated milk.

I guess in this case the real question is: was the container aseptic? Like, I've got some Land'o'Lakes half & half in my fridge that came in a sealed carton with a pull tab. If it's not aseptic it's at least aseptic-adjacent, but there's no indication anywhere on the carton.
posted by fedward at 8:03 AM on November 27, 2017

dairy will tell you if it's bad. it's really obvious. it stinks. if your milk/cream/halfnhalf smells and tastes fine then it is fine.
posted by fingersandtoes at 8:12 AM on November 27, 2017 [3 favorites]

Agreed that you should use it unless it smells bad.

But now I'm really curious about whether ultra-pasteurized milk currently sold refrigerated actually needs to be refrigerated. This link suggests yes: "UP pasteurization results in a product with longer shelf life but still requiring refrigeration." I think that because the cartons normally used are not airtight, and they're not filled "under aseptic conditions," the refrigeration is actually important.
posted by metasarah at 11:40 AM on November 27, 2017 [1 favorite]

This is incredibly simple to solve. Boil some water. Pour in your half and half. It it curdles, it's bad.
posted by DarlingBri at 12:35 PM on November 27, 2017