Formulas for Food

August 4, 2007 6:36 AM

Looking for math formulas involving food.

By math I mean anything from algebra to simple arithmatic. By food I mean caloric intake, macronutrient ratios, energy expenditure etc. Bonus points for bizarro stats regarding food. Thank you.

posted by JaySunSee to food & drink (5 comments total)

I can send you my food science class notes. They have everything from macronutrient intake to bacteria calculations.
posted by melissam at 7:54 AM on August 4, 2007

A Pint's a Pound the world around.
(as in a pint of water or any liquid with a water-like viscosity will weigh a pound.)

That's the most practical one I know. Start watching Good Eats on the food network. Alton Brown is full of these little facts.
posted by The Esteemed Doctor Bunsen Honeydew at 9:26 AM on August 4, 2007

The forums section of Cooking for Engineers (previously) has a forum called Engineer speak, where they talk about that kind of thing. They aren't exclusively formulas, but there's a few here and there.
posted by lysdexic at 12:48 PM on August 4, 2007

In that vein, a liter's a kilo. But that doesn't rhyme.

A Calorie (as seen on American food packaging) is actually 1000 calories (a kilocalorie, or kcal). A calorie is the energy used to raise the temperature of one gram of water one degree celcius. So that 100-Calorie bag of chips contains enough food energy to boil a liter of water.
posted by alexei at 6:03 AM on August 5, 2007

A rule of thumb, valid within foody ranges of its parameters: Every gram of lean protein, and every gram of carbohydrate (not counting fiber) contributes 4 kcal. Every gram of lipids contributes 9 kcal.

Here's a chart of alcohol content remaining after various cooking times. Regrettably, they don't give the equation, but you could fit a curve.

When you're making boiled candies, the reason the temperature correlates with the type of candy it will produce is that the sugar elevates the boiling point of the water. The liquid phase must remain at or below its own boiling point—so as more water evaporates, the solute concentration rises, and that elevates the boiling point further. This allows an ordinary mercury thermometer to accurately predict the water content of the candy and therefore its physical properties. If I could, I would show you the chart from p. 681 of Harold McGee, On Food and Cooking (second edition), at this point; it plots boiling point against percent sugar by weight. I think the book would interest you greatly: Many tables, though few equations, and more (qualitative) chemistry than either.
posted by eritain at 12:45 AM on August 14, 2007