Flavedo and albedo changes in 'Eureka' lemons caused by static compression and impact loading.
Underhill, S. J. R.; McLauchlan, R. L.; Dahler, J. M.;
Journal of Texture Studies Year: 1998 Vol: 29 Issue: 4 Pages: 437-452 Ref: 23 ref.
1998
บทคัดย่อ
Mature lemons (Citrus limon cv. Eureka), were subjected to increasing compression, impact and static loading, then stored at either 1, 13 or 20 deg C for 14 or 28 days. Following storage, fruits were assessed for cellular damage associated with the site of loading. Slow compression (1.7 cm plunger driven at a loading rate of 200 mm/min) resulted in cell damage in the mid to lower flavedo tissue. Tissue failure was characterized by cell rupture, with minor cell deformation and compression associated with damage to the oil glands. Impact loading caused relatively little lower flavedo damage, with most of the injury associated with the albedo, the upper flavedo and tissue surrounding the oil glands. Damaged albedo cells formed a distinct zone of ruptured and laterally compressed tissue which increased in area with drop height. Static loading (3.7 kg top weight) resulted in a similar mode of failure to that of impact loading, with extensive cellular damage observed in the lower albedo. Injury was di
stinct in that cells were not laterally compressed and flavedo damage was far more pronounced. While most of the tissue damage was directly associated with cell failure under loading, calcium oxalate crystals were also associated with some degree of cell damage. Impact loading appeared to cause the sharp crystals to puncture individual flavedo cells leading to localized cell damage. All 3 types of loading resulted in surface lesions at the point of contact. Surface damage associated with impact loading (up to 100 cm drop height) was only observed following subsequent fruit storage at 1 deg C.