Four devices for firmness measurement (8 mm Effegi penetrometer, 14 mm Effegi penetrometer, Kiwifirm and Handy Hit) were examined for their potential to predict post-storage softening that occurs during transport and distribution. Eleven lines of fruit with similar initial firmness were tested with each device prior to a simulated shipping period of 39 days at 0 degrees C. The large head penetrometer was more sensitive than the small head penetrometer, Kiwifirm, or Handy Hit in detecting softening. However, when firmness was determined prior to shipping, no device discriminated between orchards for subsequent softening. When measured by the large head penetrometer, the fruit that were initially firmer tended to have a greater degree of subsequent softening than the fruit that were initially softer. Softening was predicted by the high between fruit variability in the firmness of a 20 fruit sample measured using a large head penetrometer prior to the simulated shipping period. It is concluded that the large head penetrometer has the potential to be a useful tool for kiwifruit evaluation after storage.
