Engineered Dunking
July 25th, 2007 by Gene
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Those British engineers are at it again. We’ll see what they’re up to. Today, on Engineering Works!
A while ago, we told you how some engineers in England had figured out why cookies crumble. There really is a reason, and they found it. Now, other English engineers have figured out the best way to dunk a cookie – or biscuit, as the Brits say – in your coffee without it falling apart. They’ve even put together a mathematical formula that explains how it works.
Here it is. The average pore diameter in a cookie is equal to four times the viscosity of the coffee, times the height the coffee rises squared, divided by the surface tension of the coffee, times the length of time the cookie is in the coffee. Got that? Right.
Here’s what it means. Cookies are basically lumps of starch glued together by sugar. When you dunk a cookie, your hot coffee soaks into the spaces between the lumps and dissolves the sugar. When enough of the sugar has dissolved, your cookie falls apart into the coffee.
A big cookie maker in England is financing the engineers’ research. The company thinks that cookie dunkers might buy more of their cookies if they can dunk them with less risk of cookies in the coffee. The company plans to publish a list of their cookies, with the optimum dunking time for each kind.
We’ve had our fill of cookies for today, so we’re going to quit now. See you next time.
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