ARS | Publication request: RESPONSE OF FLORIDA GRAPEFRUIT TO SHORT-DURATION HEAT TREATMENTS USING VAPOR HEAT OR HOT WATER DIPS

Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Proceedings
Publication Acceptance Date: February 13, 2004
Publication Date: April 1, 2004
Citation: Ritenour, M.A., John, K., Pelosi, R.R., Burton, M.S., Mccollum, T.G., Brecht, J.K., Baldwin, E.A. 2003. Response of florida grapefruit to short-duration heat treatments using vapor heat or hot water dips. Proceedings Of Florida State Horticultural Society. 116:405-409.

Interpretive Summary: Heat-treatments of fruits, including grapefruit, have been shown to reduce postharvest decay and chilling injury, but can scald the peel, causing peel injury. In this study, grapefruit were exposed to hot water and vapor steam heat to reduce subsequent development of mold and to reduce chilling injury. Hot water treatment of 59 degrees F for 10 seconds or 53 degrees F for 120 seconds did not cause peel injury and reduced decay. Washing and waxing the fruit after heat-treatment reduced development of peel injury.

Technical Abstract: Heat-Treatments have been evaluated and utilized commercially to reduce postharvest decay, chilling sensitivity, and maintain quality of perishable horticultural products. Recent studies exposing grapefruit to short-duration, high temperature water (e.g., 133 to 144 °F (56 to 62 °C) for 20 seconds) have shown promise at reducing subsequent development of mold (Penicillium) and increasing resistance to chilling injury (CI) Among the most prevalent citrus decay organisms in Florida are the stem-end rots (Diplodia natalensis and Phomopsis citri). Whereas Penicillium species invade citrus tissue through wounds, the stem-end rot organisms develop latent infections within the button tissue that are more protected from physical and chemical treatments.