Tag Archives: science

Food science & history with crappy camera-phone photos

Started the food history lecture today (we spent the first week getting hung up on math assessments). Good enjoyable stuff–PK making connections between what Professor Albala was saying about prehistoric cooking practices and things he already knows about prehistory*–and it turns out that there is a downloadable course booklet that comes with each of the Great Courses. In the one for this course, the professor specifically mentioned, there are accompanying cooking activities. So I went and looked, and the first activity was a perfect hands on, homeschool type of science/anthropology experiment. Here ’tis.

Boiling Water in A “Skin” Bowl Made of Paper

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Yes, that’s a Trader Joe’s bag

Make a cup out of a large, flat piece of paper (not one that’s been cut and glued into a cup, b/c the seams will leak)–an 8″x8″ square cut from the side of a grocery bag will work well for this, as the paper is thick enough to hold the water without soaking through and 8″ is large enough that you can hold the corners without burning your fingers.

Light a candle in a holder so it’s ready to go (or just hold it in your hand and have the kiddo do the next part, assuming kiddo is old enough to have sufficient motor control). We burned a whole taper down and were just short of boiling when we finished, so I’d suggest using either a high-quality taper or a larger candle.

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No, the sink is not clean. This is not one of those blogs that pretends to perfection.

The cup may drip a tiny bit (ours did), though, so if you are using a pillar candle there’s the possibility that accumulated water will put

it out; I recommend a good taper held sideways–or just laid down with the burning end over an open area.

The kitchen sink is perfect since it’ll contain any spills and there’s water just in case something does catch fire….

Fill the paper cup halfway with water. Hold it over the candle flame. In a few minutes, the water will start to steam and then, to boil.

Stuff you can talk about while you’re waiting:

  • Why isn’t the paper burning? (It will probably smoke, and if you pay attention you may see little ember glows within it right above the flame.) You can point out that an animal skin (leather) would be even less flammable than paper, of course, and therefore better able to stand up to an actual campfire as opposed to a tiny candle flame. Plus it’ll hold more water.
  • Do you think cooking this way would be something that would be more characteristic of settled agrarian people or hunter-gatherers who had to move around a lot to find food?

We did ours, as I said, in the kitchen sink; initially I held the candle sideways and PK held the cup, but once he realized that this was going to take a while, we decided to just rest the candle on the side of the sink while I held the cup and PK did his job of cleaning the kitchen. :-) It’s fun to watch, though, especially if you look for the tiny embers that you can occasionally see through the water. Because I am a klutz, I twice spilled some water while adjusting the candle as it burned down, which means that by the end we had very little water in the “cup,” and the candle burned all the way down before the water actually started to boil–but there was quite a bit of steam by that point and the water was quite hot to the touch, so we deemed the experiment successful.

*Including the interesting fact, so PK says, that the sword was the first weapon built exclusively for fighting and killing other humans. Other weapons used for that purpose (spears, slingshots, clubs) can also be used against animals, and axes and knives can be used as tools, but swords are too big and unwieldy for either hunting or even to cut up an animal carcass; they are weapons built to be used in a situation where your opponent will not run away, but will stand and fight. i.e. there is a “rule” about the fight. He did not, however appreciate my thought that this fact suggested that the laws in pre-modern Europe and Japan (and for all I know, other places as well) that actually forbade commoners from owning or wearing swords, along with accompanying ideas about sword-carrying being a mark of nobility, effectively meant that the idea of status in complicated modernizing societies basically amounts to being able and willing to kill other humans (and therefore, to forbid others from having this power), since he is a 12yo boy and still really wants to believe in the idea of knights, soldiers, etc as protectors….

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