Quiz: Which of these liquids (in cooking) are non-Newtonian liquids?

SatNavSaysStraightOn

SatNavSaysStraightOn

Moderator
Staff member
Joined
11 Oct 2012
Local time
10:14 AM
Messages
18,430
Location
SE Australia
Website
www.satnavsaysstraighton.com
Another thread of mine about making home-made custard using a whole egg and yellow cornflour/maize flour created a single post about non-Newtonian fluids. Now you are going to need to think a little about this one and use some cooking knowledge and some of what is described below...

Being the PhD organic chemistry study that I was, and studying surface tension, I thought I would see how many of you knew which of the following food related liquids were non-Newtonian after a quick description of what makes a Newtonian and non-Newtonian fluid.

Newtonian fluid.
A fluid whose viscosity doesn't depend on gradients in flow speed. Gases and low-molecular weight liquids are usually Newtonian fluids.
non-Newtonian fluid.
A fluid whose viscosity changes when the gradient in flow speed changes. Colloidal suspensions and polymer solutions are non-Newtonian fluids.
Click to expand...

So in a non-Newtonian fluid, doubling the speed that the layers slide past each other does not double the resisting force. It may be less than double or it may be more than double. The resisting force behind how hard it is too move these layers... Or in cooking terms stir it.

So which of these food and drink related items are non-Newtonian fluids ?
  1. Ketchup
  2. Milk
  3. Water
  4. Corn starch in a paste
  5. Gravy
  6. Yoghurt
  7. Orange juice
  8. Whisky
  9. Pie filings such as pumpkin or chocolate pie (technically a liquid/fluid because it will run out eventually, just very slowly target liquid tar being a liquid not a solid)
  10. Custard

Not an easy one this one and it will take a little working out, but quizzes are not meant to be easy and this for me, is not too difficult to work out whereas the cryptic crossword clues on food and drink just have me totally defeated!
 
Question over "3".
They're undecided, as they've just discovered it can exist in another form.
It was odd enough, or so they thought.
 
With the above post in mind,
1, 3, 4, 5, 6, 9, 10.
I've been looking at this from a mechanical side
This from someone who was barred from all but Physics after the Third Year(Teachers felt it was safer), and who had a metalwork teacher, nickname "Mad Jack", who set a maths exam. One question posted on CC, took over seven pages to explain.
 
Last edited by a moderator:
classic33 said:
Question over "3".
They're undecided, as they've just discovered it can exist in another form.
It was odd enough, or so they thought.
Click to expand...
I think we'll pass on that in the kitchen though. What do you reckon?

classic33 said:
With the above post in mind,
1, 3, 4, 5, 6, 9, 10.
I've been looking at this from a mechanical side
This from someone who was barred from all but Physics after the Third Year(Teachers felt it was safer), and who had a metalwork teacher, nickname "Mad Jack", who set a maths exam. One question posted on CC, took over seven pages to explain.
Click to expand...
I'll let you know at the end of next weekend. Say Sunday 30th October, sometime in my evening.
 
And a bit of overnight research shows one is considered, if from a certain country only!

Odd that, regional variations to the rule.
 
corn starch in a paste. Google Mythbusters walks on cornstarch one word not 2 for the US version
This was an easy question.
 
Last edited by a moderator:
You must log in or register to reply here.
Back
Top Bottom