Effect of carboxymethyl cellulose/candelilla wax edible coating incorporated with ascorbic acid on the physicochemical and sensory qualities of prepackaged minimally processed carrots ( Daucus carota L.) during cold storage

Minimally processed carrots (MPC) was coated with ascorbic acid-added carboxymethyl cellulose/candelilla wax emulsion, then placed in plastic boxes with perforated polyethylene wrap, and stored at 5°C. It was found that the horizontal cross-section of samples absorbed larger amounts of emulsion than the lateral surface. The individual wax globules of the coating deposited in the interior of the damaged (by peeling) cortical cells were visualized using scanning electron microscopy. The coating improved water vapor resistance of MPC, temporarily increased the respiratory rate, decreased the activity of polyphenol oxidase, and prevented the formation of “white blush.” The acidity, total phenolic content, and texture of the MPC were not affected by the coating treatment. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh-like characteristics of minimally processed carrots through 21 days of cold storage. Practical applications The treatment of minimally processed carrots with the carboxymethyl cellulose/candelilla wax/ascorbic acid emulsion results in increased moisture retention. Consequently, the coated carrots exhibit reduced weight loss, unchanged hardness, and no “white blush.” As expected, the coating inhibited the activity of polyphenol oxidase, most likely due to the MPC surface acidification. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh-like characteristics of minimally processed carrots through 21 days of cold storage. However, the noticeable disadvantage of the coated carrots is the waxy circular deposit around the pericycle and endodermis cells.