Abstract
Aichi is the most active poultry raising prefecture in Japan. This is a report on how the pupils of an elementary school learn freshness of eggs. On inquiry they still decide freshness an old method whether the egg has shell cuticle or not. But nowadays eggs are washed by egg machines as the scale of poultry raising has become greater. So the old method of grading eggs is useless. If they want to decide freshness without breaking eggs, it is best that they decide freshness by the amount of air cell. The viscosity of egg yolk and egg albumen decreases, when eggs are kept warmly as in summer temperature. The viscosity of eggs that are put in refrigerator changes little. In elementary school, when teachers want to teach freshness by breaking eggs, they had better teach that stale eggs spread out when broken, because the viscosity is lost, but that fresh eggs keep much of their shape. And teachers should teach not only about freshness, but about quality.
