Changes in water potential, osmotic potential, and tissue electrolyte leakage during mass loss in carrots stored under different conditions

• Published in: Scientia horticulturae 2002-08, Vol.95 (1), p.13-21
• Main Authors: Shibairo, Solomon I, Upadhyaya, Mahesh K, Toivonen, Peter M.A
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Carrot; Economic plant physiology; Fructification, ripening. Postharvest physiology; Fundamental and applied biological sciences. Psychology; Growth and development; Osmotic potential; Relative electrolyte leakage; Shelf life; Water potential
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/S0304-4238(02)00034-1

Mass loss, water potential ( ψ), osmotic potential ( ψ π ) and tissue permeability of carrots ( Daucus carota L. cv. Eagle) stored for 30 days at 2 °C and 80% relative humidity (RH) (optimal shelf condition (OSC)), 13 °C and 79% RH (common shelf condition (CSC)), or 13 °C and 31% RH (poor shelf condition (PSC)) were monitored. Carrots at PSC lost the most mass followed by those at CSC and OSC. Total water potential ( ψ) and osmotic potential ( ψ π ) of the carrots at CSC and PSC did not change significantly for up to 6 days, but decreased thereafter. No statistically significant change in ψ and ψ π occurred in carrots at OSC. Relative electrolyte leakage (REL) rapidly increased after 12 days at PSC and after 18 days at CSC, at which point mass loss had exceeded 8% of original weight, considered to be a threshold for quality loss. REL of carrots stored at OSC increased only slightly and the mass loss in these carrots did not exceed 8%. Regression analysis showed that mass loss in carrots was consistently associated with REL; changes in ψ and ψ π were associated with mass loss only when carrots were kept at 13 °C. Thus, REL could be a good indicator of mass loss of carrots under a wide range of shelf conditions. The sharp rise in REL at CSC and PSC occurred when the mass loss exceeded 8%.