Abstract
Advancing in knowledge of the mechanical properties of fruits and vegetables under compression has an important significance for us in all agricultural and food engineering; harvesting, handling, storing and processing etc. Information on the mechanical properties of some agricultural products tested in this experiment is as follows:
(1) In each product, we found a considerable difference even in the same kind of products due to harvesting time, growing condition and product size.
(2) Depending on the diameter of plunger, product variety and size, the stress-deformation curves may not have the bio-yield point on them.
(3) As a rule, early harvested fruits are harder than the properly harvested ones, and as for fruits and vegetables except tomatoes etc., early harvested ones are softer and more delicate than the properly harvested.
(4) The apex resistance of fruits after harvest may become stronger than the base, except a certain kind such as citrus fruits.
(5) As for grain such as unhulled-rice, well dried grain are better than wet ones in hulling, and properly wet grain are more suitable than dry grain in crushing process.
