Starch Solution

[Slartibartfast]

G'day all!
Can anyone enlighten me on great/effective way of preparing 1 litre of 5% starch solution without it going gluggy? I'm currently blaming the hotplate!

Regards
Richard

[bindi]

I make a paste with a little water then add the paste to the 1L of boiling water.
Also check expiry date on starch.

[rae]

Hi

I like to mix the starch with enough of the water to make a smooth solution. Stir to get all the lumps out.
I then add this to the rest of the water and bring this to the boil stirring constantly either with a stirring rod or a magnetic stirrer. This has always
(Touch wood) worked for me.

I think the trick is to have a really well suspended solution first with no lumps. Its a bit like making a white sauce or gravy when you are cooking.

Good Luck

Lorrae

[Mother]

Hello all
I have just made a starch solution for the Osmosis experiment using dialysis tubing etc. I made 500mls using 10g of potato starch. This is good enough for any experiments that requires starch solution.
Hope this helps
Cheers
Mother

[ri]

Hi All,
I have found that a starch solution over about 1%, however prepared, will go solid at room temperature, let alone in the fridge where it must be kept long term to inhibit moulds. If you are using dialysis tubing to test the presence of starch with iodine solution, it needs to be able to be 'pourable' and iodine will pick up the presence of starch at concentrations of about 0.1% in food testing.
These lower concentrations of starch makes it easier to prepare and the suggestions of mixing with a small amount of water first sound great.
Cheers,
~Robyn

[Slartibartfast]

Thanks! 1% solution makes it much far more managable with the dialysis tubing - it was far too thick beforehand to pour readily.

Regards
Richard