Abstract:
A study on the effects of 5 levels of temperature; 10, 15, 20, 25 and 30 "C and ethyleneconcentrations at 0, 5, 10, 20 and 40 ppm on the peel color and quality changes of 'Puang-Thong'mandarin after harvesting was conducted. The results showed that the optimum temperature fordegreening was 25 "C in which the peel changed from green color to yellow within 15 days.However, the effect of ethylene for degreening the peel color also showed that the treatment underethylene at 10 ppln for 24 hours resulted in the color change within 6 days. Treatment with ethyleneresulted in higher carotenoid content while chlorophyll content was reduced. It was also found thathigher concentrations of ethylene (20 and 40 ppm) for 48 hours resulted in higher rate of decaycaused by mold. On the other hand, treatment with lower concentration of ethylene (5 ppm) for 24and 48 hours resulted in a slower change of the peel. Degreening by using 10 ppm ethylene for 24hours could prolong the storage life of the mandarin for 112 days, at 5 ํC. Although the storage lifewas not different between degreened and non-degreened mandarin at 5 ํc, the degreened mandarinkept at higher temperature seemed to have the shorter storage life. For sensory taste, the panelistspreferred the degreened mandarin to non-degreened due to their desirable yellowish color, taste andflavor.