45

When a product says "refrigerate" or "freeze", the temperature they're asking you to keep it at is not a mystery -- most refrigerators and freezers maintain an expected temperature range.

But other products indicate "room temperature" or that they should be stored in a "cool, dry place". Are there actual temperature ranges associated with these set phrases?

I grew up in North America, in a household where we couldn't afford to overly heat the house in the winter, or cool it in the summer. "Room temperature" was, therefore, 50-55°F (10-12.7°C) in the winter, and 85-90°F (29-32°C) in the summer. My perception of "room" temperature is similarly skewed -- this isn't at all "normal" from a N. American perspective, where most of my peers like to keep their houses at around 77°F/25°C in the winter, and 67°F/19°C in the summer. But I remain confused, at least, from a culinary perspective of what exactly I'm being asked when a product indicates these set phrases.

As a concrete example: I recently bought a tub of ghee. It indicates to me on the labelling that it does not require refrigeration, can be kept at "room temperature", and should be stored in a "cool, dry place". My apartment is 80°F/26.6°C right now -- is this "room temperature"? (It'll cool to ~61°F/16°C overnight.) In the meantime, it's significantly warmer than the store shelf I bought it from, and the ghee has gone from a soft solid to pure liquid. This change of state (solid -> liquid) is what prompted my concern that I'm misinterpreting "room temperature" in terms of food temperature and safety.

12
  • 7
    Another fat that's definitely storable long term without refrigeration but solidifies in a cold enough room is olive oil. Slightly cooler than for ghee, but I'm mean enough with the heating and unbothered enough by the cold to see it. My kitchen normally only gets cold enough for it to go cloudy and thick (though there have been exceptions) but I don't take it in the camper van in winter in case I can't get it out of the bottle.
    – Chris H
    Sep 7, 2022 at 6:03
  • 2
    I suspect though, that this difference is less important for food safety than for some cooking steps that rely on the behaviour of fats at different temperatures (like you'd soften butter before creaming with sugar) or in baking when yeast works much more slowly colder
    – Chris H
    Sep 7, 2022 at 6:05
  • 8
    I'd always refrigerate ghee, whatever it says on the packaging. It will go rancid in fluctuating temperatures, long before its 'best before' date.
    – Tetsujin
    Sep 7, 2022 at 8:11
  • 13
    Up until about 2019, the "kilogram" was based on a real, physical object housed in Paris. Now I'm imagining an official "room" from where all "room temperature" is based off of.
    – BruceWayne
    Sep 7, 2022 at 14:22
  • 11
    @BruceWayne: behold the room temperature room! Sep 7, 2022 at 14:46

3 Answers 3

31

"Room temperature" as used for testing, analysis, and validation purposes generally falls within the range of 65F-75F (18C-24C). Published research will typically specify temperature ranges used.

Both the FDA Food Code (2017) and Canadian Food Retail and Food Services Code (2016), providing guidelines for inspection activities, take an outcome-based approach and do not reference specific storage temperatures or humidity levels as products stored unopened in these conditions are designed to be safe or are self-evident if spoiled/unsafe - mouldy potatoes, rusted or swollen cans, etc.

In most jurisdictions in North America, refrigerator and freezer temperature conditions are often codified in laws and may be required to be explicitly labelled for consumer protection since pathogen activity is not as readily evident as spoilage - some Listeria, for example, can reproduce in food below 40F/4C, making both maximum storage temperature and duration needed.

A better source for optimum room temperature conditions would be your local building code, though most will specify the same range noted above and humidity <60%. If it's comfortable for humans, it's most likely suitable for products designed for those conditions.

For your ghee example - it originates in India for preserving butterfat at 30C+ temperatures and seasonal relative humidity close to 100%. When properly stored in an airtight container there is no water available for microorganism activity, and the concern is more for long-term quality decline due to oxidative rancidity.

8
18

It depends on whether you are talking about food safety, or food quality.

When you are talking about food safety, then "room temperature" is the complete range between 4°C (40°F) and 60°C (140°F). There are upper limits for the time that refrigeration-needing items can spend in this range (anywhere in it). "Cool, dry place" is not defined from the point of view of food safety.

When it comes to food quality, there is no strict definition. There are optimal conditions hiding behind each of these terms, and the farther you go from them, the quicker your food will deteriorate, in noticeable ways like mold, or unnoticeable like the slow loss of aroma in spices. So, it is not a range, it is more of a target with a lot of leeway.

For the target temperature, I would say that it is about 22°C (70°F) for "room temperature" and 15°C (60°F) for "cool, dry place". I don't have references for this, but it is quite compatible with both the conditions at which many foods do well, and with the actually available conditions in many households in the western world (although this is changing - many modern households no longer have a 15°C (60°F) cellar or pantry).

5
  • 2
    The ideal room T° according to this commercial document is exactly 23°C (73.4°F), but back when I was working in the pharmaceutical industry, it was defined as 10°C-30°C (30°F-86°F) for the companies I worked for...
    – Fabby
    Sep 7, 2022 at 14:50
  • 4
    @Fabby these sources are interesting, but neither of them are about food storage. So there is not a perfect overlap with the culinary sense of the term (nor would would it be expected).
    – rumtscho
    Sep 7, 2022 at 14:56
  • 2
    That's why it's a comment and not an answer... 😉 @rumtscho
    – Fabby
    Sep 7, 2022 at 14:58
  • 1
    Rumtscho, please don't put me in a room at 60°C! I'll be nice! Sep 7, 2022 at 21:57
  • 1
    @DawoodibnKareem: 60°C? That's kind of chilly for a sauna, can you please turn up the heat a bit? :D (But seriously, humidity and physical activity make a huge difference. Try doing heavy physical exercise at 60°C and 100% RH and you'll pass out in minutes and probably die if not rescued. Sit naked in a dry room at 60°C and you're probably fine indefinitely, as long as you have enough water and electrolytes to drink to replace what you're sweating out.) Sep 9, 2022 at 8:36
10

If you are reading this in a recipe, as opposed to product packaging, then "room temperature" and "cool" are going to vary according to the writer. That is, those terms mean different things for a Finnish recipe author than they do for a Brazilian one.

As a specific example where this could affect cooking is making dosa batter. Indian recipes often tell you to ferment it at room temperature, but the temperature they mean is 26-30C. If you try to ferment it at American room temperature of 21C, the batter will not ferment properly or will take days instead of hours.

Conversely, on pizza forums I've handled questions from Indians who had problems making pizza dough because room temperature ferments were too warm and the dough overproofed.

So, to answer your question: They do not mean a specific temperature if found in a recipe.

1
  • 5
    I think they /do/ mean a specific temperature in a recipe, just not the same temp in different recipes :) Sep 7, 2022 at 21:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.