'Can it be hot, though?' said Isla, looking at a cold pasta salad on a morning in the last week of March when it was 4°C outside and sleeting sideways at the bay window. It was a fair question. Her school dinners are, in her words, 'always cold anyway', and she had spent a week watching a girl in her class eat hot soup out of a flask at the next table. I said I'd think about it. Then I borrowed Steve's.
Four weeks, roughly
Steve's flask is a dented green steel thing from his bus-driving days, with a litre inside it and a cup for a lid. It was enormous. Isla took it to school on Tuesday 24 March in a carrier bag, holding it like a trophy, and it did keep a mess of pasta warm until noon, but she couldn't eat a third of it. That was week one.
Week two was over Easter, when the proper one arrived: a 300ml food flask for £14, stainless steel, with a wide mouth so a spoon actually fits. We tested it at home through the holidays, at lunchtime, with me standing there with a probe thermometer like a woman in a laboratory. From 13 April it went to school. So four weeks is generous, because two of them were holidays, but the trial ran on all the same.
The method I ended up with is boring. Boiling water from the kettle goes in the flask while the food heats on the hob, lid on, and gets tipped out just before filling. The food has to be properly piping. The flask gets filled to the very top, because a half-empty flask loses its heat faster. And the lid gets screwed down properly, which I failed to do on the first Friday. The tomato soup travelled sideways through the lunch bag, and the bag smelled of it until the following Tuesday, even after a wash.
What stayed warm and what didn't
- Home-made tomato soup, 38p: still hot at noon, and the best result by some distance
- Sausage and beans, 61p: good, though Isla says beans touching sausages is 'a lot'
- Short pasta in a loose tomato sauce, 29p: fine, as long as the sauce is runny enough that the pasta can't drink it all
- Mac and cheese: set like a brick by twelve, and was described, accurately, as wallpaper paste
- Chicken noodle soup: the noodles swelled until there was no soup left, only noodles
- Scrambled egg: I don't want to talk about it
Does it stay hot, and what does it cost?
I wouldn't send hot food in a flask that wasn't still hot when it was eaten, so I checked. On a Saturday I filled the flask the way I'd fill it for school, left it on the counter, and put the probe in at five past twelve. With the flask preheated, the soup read 67°C. Without the preheat, it was 51°C, and I wouldn't send that to school. The figure I'd read for keeping hot food hot is 63°C, which is why I stopped being casual about the preheating. That's what we do, and why. Read your own flask's instructions, and I asked the school office, who said sealed flasks are fine.
It doesn't save money. A flask lunch with fruit and a flapjack comes in at about £1.46, against Isla's usual £1.39, because the hot fillings cost a few pence more than a cheese portion and a handful of cucumber. The £14 for the flask and £6 for the thermometer are on top of that. What it buys is a girl who comes home from school and says the lunch was good, which is not a thing I can put in the lunchbox spreadsheet and I tried.
What I'd change
I'd have bought the flask the same week she asked, and not borrowed a litre of steel from a retired bus driver. I'd also have made a rule early on that new recipes are tested on a Saturday, with me watching, and not on a Wednesday, with a dinner hall watching. The day the mac and cheese set solid, Isla ate the sandwich I'd stuffed in as a back-up, handed back the flask without a word and went off to netball.
Isla's current favourite is soup with a bread roll on the side, and she has asked whether macaroni cheese could be 'less glue-like'. I have said no. Then, because she looked so hopeful, I have said I'll think about it, which is what I said the first time.
