Firmness of Tomato Fruit Tissues According to Cultivar and Ripeness

The firmness of tissues of a transverse equatorial slice of fruits of ‘Flora-Dade’, ‘Walter’, ‘MH-1’, and ‘Homestead 24’ tomatoes ( Lycopersicon esculentum Mill.) was determined at different stages of ripeness by use of an Instron Food Testing System. The outer, radial, and inner pericarp tissues of ‘Flora-Dade’ and ‘MH-1’ were firmer than those of ‘Walter’ when ripened 6, 8, or 10 days at 20°C after incipient color formation. ‘Walter’ tissues were intermediate in firmness between ‘MH-1’ and ‘Flora-Dade’ at the mature green stage, but had softened much more than either at the incipient color stage. Most of the softening of the tissues of the three cultivars had occurred by 4 days after incipient color. The placental tissue of ‘Homestead 24’ fruit was much firmer than that of ‘Walter’ and ‘Flora-Dade’ over a period of 7 to 19 days after incipient color stage, although the outer pericarp tissue was much softer than that of the latter two.