I have a coffee maker in my office, but no fridge for my cream! Unfortunately, even a mini/bar fridge would be too big for my office.
What other options do I have for keeping cream good for 8-10 hours? I can bring just what I'll use for the day in the morning. The room is kept at 20-22C all day. How long can cream be stored at room temperature before it is risky to use?
Companies (including Nestle) make creamers that do not require refrigeration. They are likely available in your local grocer, you just need to check the label and make sure refrigeration isn't required.
If you are paranoid about potential bacterial growth or contamination (like me) you may check into bulk buying the single serving creamers that they use at restaurants. They require no refrigeration either and are sealed until use.
If you are looking to keep "real cream" cold for 8 to 10 hours, you may want to look into some sort of freezable lunch bag or small ice chest that will stay cold and takes up less space than a mini-fridge. This would require substantially more effort, but may be worth it if you are particular about your cream. Also from the comments below, you may look into a double wall vacuum thermos. They are increasingly popular and come in a wide variety of qualities and prices, so do your research before buying.
There are some really small coolers that go for about $20, powered by USB. This means you can use pretty much any standard USB wall charger capable of delivering 2.5 watts to power one. It'll hold a 12 ounce jug of milk and keep it cold.
Stats says it goes down to 46°F. While technically milk should be stored below 40°F for absolute safety and quality, most insulated lunch boxes with a 'freeze pack' get a bit warmer than that after a few hours.
Frankly, you run a small risk using anything but a refrigerator. I don't think you'd run into a problem, but the only totally 'safe' bet in your case is creamer that doesn't require cold storage.
It sounds like both you (and @Chris) are talking about liquid cream or creamers that resemble liquid milk in some way. If you're willing to stray from that...
Though I wouldn't eat them myself, consider also powdered creamers. These can be based on dried milk (which is very nearly still food), or on non-dairy stuff (partially hydrogenated oils, etc., which I don't know what they are).
As for the safety aspect of your question, you have basically zero time at room temperature for milk to be truly safe. According to this page, bacteria starts growing at about 45°F / 7°C; it'll get there pretty quickly if not cooled. Practically speaking, you have some time but it is not hours. I thought I had seen a chart of time-at-temperature (e.g., safe for 1 hour at temperature X, 30 minutes at temperature Y, etc.) but I can't find anything like it now.
Maybe a bowl with ice in it, perhaps an insulated bowl or container that is big enough to hold the creamer container and sufficient ice to keep it cold. I worked at a temporary office for an insurance co. and that's how they kept it cold. The small cooler is a pretty good idea also.
Some options.
Have you tried freezing the cream, then using it as it melts? This works for bottles of milk, but I have never done it with cream.
Fill an unglazed clay pot with cold water, putting in cream in a sealed container in the pot, was the water enverperates from the damp sides of the pot, it cools the pot. To speed up the process put the pot in front of your desk fun.
A sealed container in the flush tank of a well used WC may work, if the cold mains water is cool enough, when camping a river is used in that way.
Full disclosure: The same question was asked at Seasoned Advice and I am re-posting my answer from there with minor adjustments.
I would invest in a small thermos bottle, about the size of what you need for one day. They are not only designed to keep hot food hot, they can also keep cold food cold. Choose a size that will be as full as possible when you start, it will keep better. I prefer stainless steel, because it can be cleaned easily and thoroughly, even in case something goes wrong, like a forgotten thermos that reappears after a while. (Ask me how I know >.<)
This is what the small B&B we were staying at a few years ago supplies to their guests. If it’s good for an early morning tea, it’ll be good for afternoon coffee as well:
If you want to go all the way, you can pre-chill the container, then fill it with well-chilled cream from your home fridge. You could even freeze some of the cream as ice cubes, if you find that it doesn’t stay cold enough until the end of your work day or your last coffee break. Store the thermos away from heat sources and not in warm sunlight, of course.
Note that you also have the “two-hours in the danger zone” buffer and that “unsafe” doesn’t automatically mean “spoiled”. Especially when the cream is still quite cold and only shortly after the two-hour window the risk for a healthy adult should be small. No recommendation, just a thought.
