The digestion of bread commences in the mouth, where, under the influence of the saliva, the starches are converted into dextrin and maltose. Thorough mastication is all-important lor this process. The crust of bread, and also various special forms of bread, such as rusk, are more easily digested, because their starch has been already partly converted in the process of manufacture. New bread is indigestible because of its liability to form doughy masses, which interfere with the ferment getting proper access to the ingredients. Bread is very well absorbed; the proteins in bread, however, are less completely absorbed than are the proteins in meat Brown bread and wholemeal breads are less completely absorbed, on account of their greater richness in cellulose. The nutritive value of bread is considerable. The ratio of proteins and carbohydrates (1: 8) is too low to be a perfect food, and its deficiency in fat has already been referred to. Various means are adopted to increase the nutritive value of bread, e.g., baking the bread with skimmed milk, adding pease meal, meat, or casein. A good example of a bread with increased nutritive value is Hovis, a germ bread containing extra proteins and also fat (p. 89).
Bakers produce various types of loaves - pan, household french, cottage, etc. The chief difference is the type of crust and the porosity of the bread. The pan loaf is generally the most porous, and consequently makes the best toast.
Toast is bread browned by heat in front of an open fire, the starch being partly converted into dextrin in the process. The additional caramel or flavour and dryness acquired lessen the time of digestion of toasted as compared with fresh bread by about one-third. A slice of bread if cut sufficiently thin toasts dry and crisp throughout, but if thick the outer layers are scorched while the mass within may become softer than before toasting.
Slices of bread put into a cool oven and slowly dried, and very slightly browned, make a very pleasant change. The slow baking transforms the starch into dextrin. The bread is hard and needs a great deal of mastication, and with a plentiful supply of butter makes an excellent food for children. Many rusk biscuits are prepared in this way.
Another method of presenting bread to people with weak digestion is by giving very thin slices of bread dipped in milk and slowly browned in the oven.
Buttered dry toast is still another way of serving bread. The crisp toast is buttered when hot, and the fat droplets penetrate it. This is a good method of giving an extra supply of butter.