Most foods can be preserved for a long time if they are frozen quickly and kept at a low temperature until ready for use. Slow, natural freezing destroys food because the low temperatures draw all the water from the tiny cells of the food, affecting color and flavor. Clarence Birdseye invented a way for quick freezing in 1921. This method prevents breakage of the cell walls because the freezing process is so fast. Thus, in quick-frozen food most of the flavor, color and firmness is retained.