Cooking For Engineers

[Tenzint]

Can any of my learned friends tell me what the density of a basic puff pastry is? Failing that, can anyone tell me how to work it out?

I eagerly await your answers!

[Dilbert]

that's easy.

weigh the pastry sheet

measure length, width, thickness

multiple length x width x thickness = volume
divide weight by volume = density, in whatever units you're working with.

I'd recommend doing the measuring on an unbaked sheet.
once it bakes and puffs up, measuring its volume is ahhhh, slightly trickier . . . .

[Tenzint]

Thanks so much....all a bit confusing for me, but I'll give it a try!

[Tenzint]

Okay, so I tried that, but cannot get it right.

Maybe someone can help me.

My pastry sheet weights 440g. The height is 4 mm. The length is 340mm, the breadth is 235 mm.

So, strictly speaking I should be able to say:

4 x 340 x 235 = 319600 (volume)
then, I should say

440g divided by the volume and this is where it all goes wrong for me.

I guess I have to have the "mm / g" all converted to 1 thing??

Anyone who can assist will get my eternal gratitude.

Thanks

[Dilbert]

actually, you're doing the math right.

440 grams divided by 319600 cubic millimeters = 0.001376721 grams per cubic millimeter

a cubic millimeter is a wee tiny bit of dough - more commonly density is described as grams per cubic centimeter - or

440 / (0.4x34x23.5) = 1.376720901 grams per cubic centimeter (g/cc) - for the unbaked sheet

when baked, two things happen: it puffs up so the volume increases - and typically it does not puff up uniformly meaning that measuring the "thickness" of even a flat sheet is much more difficult
and
water is driven out of the dough - which decreases the mass

[Tenzint]

Excellent, I'm relieved to know that I am on the right track.

Thanks for the great answer and explanation....my external gratitude is yours!

But let me warn you, I'm on a mission to learn, so prepare yourself for some questions.

Thanks again