The common thickening agents are flour, corn starch, rice flour, potato flour, arrow root, eggs; also gelatin, sea moss, junket for milk, and pectin of unripe fruits stiffen liquids on cooling.

Proportions

One level tablespoon of flour will thicken one cup of liquid for soups.

Two level tablespoons of flour will thicken one cup of drippings or other liquid for gravies and sauces.

Three level tablespoons of browned flour will thicken one cup of liquid for gravy.

The thickening power of corn starch is about twice that of flour.

Four level tablespoons of corn starch will stiffen about one pint of liquid, as in corn starch pudding.

Two good sized eggs to one pint of milk make a custard one egg to a cup for soft custard or baked cup custard; three eggs to a pint of milk for a large mold custard.

One level tablespoon of granulated gelatin will stiffen about one pint of liquid, if cooled on ice.