I would hazard to say that safe food storage temperatures are general knowledge. If you don’t know what they are, then I’d encourage you to pay more attention to food safety, unless you enjoy full digestive purges:
- <0 F for frozen food
- >32 to <40 for refrigerator food
But these temperatures are for static storage. 0 F isn’t cold enough for the act of freezing, because it’s too slow and allows big ice crystals to develop in the food during the process. Sure it’ll still be safe to eat, but the quality will suffer. This dilemma has long bothered me as a gardener, hunter, and possessor of meat-cutting skills. How do I freeze that which was never frozen without adversely affecting its cellular integrity?
Vitrification would work, but I’m apparently the first person to ever search the internet for “how to vitrify beef”. So I’m guessing it’s not practical, or perhaps it’s very expensive.
That option ruled out, I’m left with one choice: cool things as quick as possible. I surmise 3 methods:
- Flash freezing
- Blast freezing
- Just freeze things in as low a temperature as possible
I’m not going to source liquid nitrogen, so option 1 is out. Nor will I go buy dry ice every time I want to freeze things. Blast freezers are more assembly line industrial systems, so obviously I’m not going that route either. Which leaves option 3.
Sushi restaurants accomplish option 3 with medical-grade freezers, which get as cold as -123. They also cost thousands, which I didn’t want to spend. But in my searching, I found a growing market for ultra low-temp consumer grade freezers. Apparently enough people wanted these that they’re available for reasonable prices. And so, I got this little number:
3.5 cubic feet, with a low temperature setting of -40. Not bad. And after adding some cold packs to stabilize it, and using an expensive thermometer that could actually read temps that low without malfunctioning, it goes even lower.
So far I’ve only used it a couple times, and I haven’t eaten what I froze in it yet, so the verdict is still out. I’m hopeful though. Here’s to some non-mushy frozen food!
–Simon