ABSTRACT
Optical density measurements have long been known and used by researchers to nondestructive^ assess maturity in blueberries (Birth and Norris, 1965; McClure et al., 1975; McClure and Rohrbach, 1978). We have also known that there is variability in the optical density measurement. In the development of the M-Belt sorter, Rohrbach and McClure (1978) reported that upon repeated classification of blueberries into three ripeness categories only 66% to 73% of the berries were reclassified into the same ripeness category upon the second sorting.
