622 Produce Degradation: Reaction Pathways and their Prevention
Chilling produce is not necessarily all bad.^30 For example, slight chilling can
result in improved sweetness and texture of stored sweet potatoes. A cold treatment
improves the ripening and sweetness of harvested pears. Night temperatures in the
chilling range result in improved color of oranges.
Wade^30 pointed out that attributing tissue damage observed in products stored at
lower temperatures to chilling may not always be appropriate. Since chilling extends
shelf life, senescent disorders may have time to develop in chilled tissue. Such
disorders may never be observed when products are stored at higher temperatures
since the development of tissue disintegration or disease may occur before senes-
cence symptoms are observed. Thus, in some cases, damage attributed to chilling
FIGURE 20.11Symptoms of chilling injury on oranges include pitting and brown discolor-
ations. (Photo courtesy of A.A. Kader, University of California, Davis.)
FIGURE 20.12Tomatoes stored 3 weeks at 5°C followed by 1 week at 20°C show symptoms
of chilling injury including pitting, discoloration, decay, and uneven ripening. (Photo courtesy
of C.Y. Wang, Produce Quality and Safety Lab, USDA, Washington, DC.)