The amorphous part of starch in fresh bread, and in fresh pastes and solutions of starch: (preliminary publication)

Abstract

AbstractThe V‐pattern of starch is difficult to understand. It is the x‐ray pattern of starch in fresh bread; and it is the x‐ray pattern of starch pastes and of starch solutions, after dehydration with alcohol.A real explanation of this x‐ray pattern cannot yet be given. But a series of facts found since 1930 makes another interpretation more probable than the one published then. It now seems most likely to be the superimposition of two patterns: an amorphous pattern of starch and a purely crystalline V‐pattern. But the old explanation still remains a possibility. When the new explanation is accepted, the change in the starch during the staling of bread is to be explained as the crystallization of the amorphous part of the swollen granules to a crystalline substance with a B‐pattern.And, on this basis, the micels in dilute fresh starch pastes and in dilute fresh starch solutions are to be considered as being chiefly amorphous. In very concentrated pastes and solutions they may be partly crystalline (with V‐pattern).