This section is from the book "A Treatise On Flour, Yeast, Fermentation And Baking Together With RecipesFor Bread And Cakes", by Julius Emil Wihlfahrt. Also available from Amazon: A treatise on flour, yeast, fermentation and baking, together with recipes for bread and cakes.
The quantity of water which a barrel of flour will absorb depends upon the strength of the flour, strong flour taking considerably more water than soft flour, also machine-made dough will take more water than a hand-made dough, and again a high-speed dough mixer will admit more water than a low-speed mixer.
The direct advantages derived from proper mixing are increased yield, more whiteness, better bread by being more nutritious, or more economical manufacture by saving of ingredients. This increase in yield is due to the development of the gluten, thereby decreasing the fermentative period and consequently increasing in the same proportion the stability of a flour and making possible the admission of more water.
The amount of water used to a barrel of flour differs in accordance with the different kinds of bread on the market. Dough for pan loaves should be made softer, than dough for loaves to be baked directly on the sole of the oven.
Of course, the baker himself must use good judgment and consider the quality of bread before he forces excessive yield.
The yield, therefore, is dependent first on the method employed for mixing, secondly on the kind and amount of ingredients added to a dough, and third upon the kind of bread made from such a dough.
The direct question of yield remains a much contested question and no answer to suit all circumstances can be given.
The aforestated contentions are for comparison of doughs made with the same amount of yeast. The amount of yeast used greatly governs yield. A cool dough, with plenty of salt and yeast, has a stimulating effect not only on the yield, but also on the quality and keeping quality of the bread.