Comparison of a new apple firmness penetrometer with three standard instruments

• Published in: Postharvest biology and technology 2000-07, Vol.19 (3), p.201-209
• Main Authors: DeLong, John M., Prange, Robert K., Harrison, Peter A., McRae, Kenneth B.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cortex firmness; Food industries; Fruit and vegetable industries; Fruit quality tester; Fundamental and applied biological sciences. Psychology; Malus x domestica Borkh
• ISSN: 0925-5214; 1873-2356
• DOI: 10.1016/S0925-5214(00)00097-1

The performance of a newly developed firmness penetrometer (fruit quality tester — FQT), was evaluated over two growing seasons with poststorage apples against the Effegi, Magness-Taylor (MT) and electronic pressure tester with the speed control engaged (EPT-SC). The FQT was operated in the: (a) standard (FQT-Std); (b) MT (FQT-MT); and (c) EPT (FQT-EPT) modes with the latter two simulating the operation of the MT and EPT-SC devices, respectively. ‘Cortland’, ‘McIntosh’ and ‘Northern Spy’ fruit were stored for 3–14 months in controlled atmosphere (CA) conditions and were then held at room temperature for 1–7 days, following which firmness was measured by four operators with each of the six instruments or modes. The ten cultivar/storage/poststorage fruit lots were designated as either hard or soft if the poststorage firmness average for the lot was ≥ or