Studis on Mechanical Properties of Agricultural Products (Part III)

On Strength Change of Apples, Pears and Peaches after Harvest

Abstract

Apples (KOKKO, KOGYOKU, INDO), pears (NIJISSEIKI) and peaches (HAKUHO) were test ed for their mechaical properties. The results were as follows:
1) If the grade, kind, variety, quality, growing conditions, harvesting time and the handling methods after the harvest were the same, the rupture point of each agricultural product was almost equal (Fig. 3).
2) The handling method of agricultural products after harvest, the method of transportation such as by cold storage car or normal car; severity of vibration in transit showed an effect on the rate of post-maturation and softening of the products.
3) If the agricultural products had the same storage conditions, temperature and humidity, its creep deformation and unrecovery deformation tended to increase respectively, on account of the postmaturation and the softening.
4) Softening rate of products tended to differ on account of their harvesting time.
5) In general, agricultural products have different strength at various times after harvest, therefore the relative strength among varied agricultural products should be determined at either the harvest time or eating time.
6) The change of damage volume by the falling impact tests was not observed during 5 days after the test.