Fats are added to doughs to make the product brittle - friable - "short," and to enrich the mixture. The fat counteracts the adhesive properties of the gluten and starch in flour.

Pastry flours contain less gluten than bread flours and so require less shortening.

Butter and oleomargarine contain about one-eighth water and salt, and thus have less shortening powers than lard, drippings, cottolene, and the like, which contain no water.

Two cups of flour (eight ounces) made into puff paste requires eight ounces (one cup) of shortening.

Two cups of flour in ordinary pie crust requires four ounces (one-half cup) of shortening.

Two cups of flour in cookies requires four ounces (one-half cup) of shortening, or less.

Two cups of flour in cake requires about three ounces of shortening.

Two cups of flour in short cake requires two ounces (one-fourth cup) of shortening, or more.

Two cups of flour in tea biscuits requires one-half to one ounce (one to two tablespoons) or more of shortening.

In yeast doughs less shortening is used - from one-half to an ounce to two cups of flour. The tenacity of the gluten is required to hold the carbon dioxid gas slowly formed by the yeast, hence too much shortening prevents proper rising.

Shortening for batters may be melted and mixed in, but in doughs which are to be rolled - pastry, cookies, short-cake, biscuit, etc. - the fat should be cold and hard and cut into the flour with a knife, or rubbed in with the tips of the fingers.