Why does starch solution thin when stirred?
In: 4
The solution is called thixotropic, which means its viscosity is dependent on the time it has been agitated.
Imagine a bowl of cooked spaghetti. Trying to stir it is initially difficult because the spaghetti strands (in your case, gluten molecules) are bundled together. As you stir, the spaghetti tends to align with the direction you are stirring, reducing the required force needed to stir. Effectively the solution has become thin because the molecules are no longer bundled together. Once you stop stirring and let the solution sit, the molecules start to settle and bundle together, increasing the viscosity of the solution again.
Because its a non-newtonian fluid unless you happen to add too much water ( same for ketchup btw thats why we shake / tap the bottle so as to agitate the particles and break the bonds making it squirt out)
Latest Answers