Fruit Firmness Measurements in Red Raspberry1

Abstract

Abstract Fruit firmness for 55 red raspberry ( Rubus idaeus L.) clones was determined at 2 locations with a Hunter Series L. portable pressure gauge. The force required to close the opening in the fruit, termed compression, and the force required to release juice, termed exudation, were measured when force was applied at right angles to the long axis of the fruit. Compression values for the firmest clones, SHRI 6820/54, SHRI 6820/41, SHRI 705/32, ‘Glen Isla’ and SHRI 6820/35, were 2 to 4 times greater than for the clones with the softest fruit. For compression values, significant correlations were obtained over clones for years and for locations. Compression and exudation values were significantly correlated.