Australia's Science Forum

I order Soluble starch from _____________, and its a pale yellow. It should not be Yellow surely.

I planning on shopping at Woolies, can I buy corn starch and use that????????????

Just need to make up a Starch Solution.

Corn starch is starch. We have always used potato starch here, but that is only because it has always been here and I have never had to replace it in 21 years. If I had to replace it, cornflour it would be, as it is very cheap by comparison. Maybe they sent you custard powder by mistake,

I once ordered starch from Govt. stores & was sent corn flour, (it would not dissolve and would not work)
I once ordered Starch from "Silform" it was orange & did not work

I think someone from here suggeseted this a while ago, so I can't take credit for the idea, but just collect some of those biodegradable packing peanuts, they're usually made of cornstarch. I have a big bag stashed in a cupboard, & when a simple starch solution is required I just dissolve a handful in water out of the kettle, then filter it. Works a treat. That's for diffusion demos etc, but if you need to make up solutions of known percentage, you'd need powdered stuff. I get mine through Omega.

I have used cornflour for the last 15 years and have had no problems.
My method is to mix a little of the powder in water then add hot water and boil for a minute or 2 to "crack" the starch granule.
If you don't boil it separates out.
This give a whitish, viscous liquid that has the tendancy to stimulate crude comments and discussions from the students.

Somebody awhile back on here suggested corn flour to me when I could nolonger get starch from Coles. I haven't any trouble and nobody has said anything. So I guess it's been working.

You don't have to boil the cornflour. Just mix with a little cold water and add boiling water. The boiling water is hot enough to "break" the starch granule.

I use the biodegradable beans with great success.
Just put 3-4 in 100ml hot water and stir to dissolve.
Love it.
L

Thank you everyone for all your help.

I used corn flour the other day to make a starch suspension - as long as it went black in iodine its all good.
I also have the packing beans in a box in the compactus, I use them sometimes.

Cook rice then use the water!

Yes! I always use rice water
The Best!