Ontario Teachers' Manuals: Household Science in Rural Schools

by Ontario. Department of Education

EXPERIMENTS IN USING STARCH FOR THICKENING

(Any powdered starch may be used)

1. Boil ¼ cup of water in a small sauce-pan. While boiling, stir into it ½ tsp. of cornstarch and let it boil one minute. Observe the result. Break open a lump and examine it.

2. Mix 1 tsp. of cornstarch with 2 tsp. of cold water and stir into ¼ cup of boiling water. Note the result.

3. Mix 1 tsp. of cornstarch with 2 tsp. of sugar and stir into ¼ cup of boiling water. Note the result.

4. Mix 1 tsp. of cornstarch with 2 tsp. of melted fat in a small sauce-pan and stir into it ¼ cup of boiling water. Note the result.

CONCLUSIONS BASED ON THE FOREGOING EXPERIMENTS

1. Starch granules must be separated before being used to thicken a liquid:

2. The liquid which is being thickened must be constantly stirred, to distribute evenly the starch grains until they are cooked.

White Sauce