Some considerations on precooling of fruit and vegetable in transit at ambient temperature.

Changes in temperature of precooled spinach transported by truck at ambient temperature under foundifferent conditions observed in 1985和1986. Additional examinations for determining changesin respiration rate of several fruits and vegetables affected by rapid elevation of temperaturewere carried out under simulated conditionsusing an apparatus automated by microcomputer.1)模板spinach packed in carton box，precooled at 5c或at 15c and transported under uninsulated condition elevated rapidly duringtransportation,temperature in case of Rapid elevation of temperature in case of ambient temperature at下一个morningspinach packed in foam-plastic box也被监测。On the other hand，spinach transported under insulated condition covered by foam-rubber sheet maintainedat low level below 10 C. Changes in freshness of spinach at ambient temperature aftertransportation were not affected by precooling temperature.2) Carbon dioxide output and oxygenuptake of several fruits and vegetables increased rapidly to peak value with rapid elevation oftemperature from 5c to 35c，and then decreased gradually to constant level at 35 C. This excess acceleration of respiration ratewas observed significantly at higher rate of temperature elevation Little excess acceleration wasobserved in case of 10 C elevation of temperature.3) From the results obtained above，这是关于fruits and vegetables in transit at ambient temperature may not be必要的to precooled at extreme degree of low temperature such as 5 . In addition,elevation of temperatureduring transportation kept within 10 C may be favorable for keeping quality of fruits andvegetables, judging from the standpoint of their physiological response

Changes in temperature of precooled spinach transported by truck at ambient temperature under foun different conditions were observed in 1985 and 1986. Additional examinations for determining changes in respiration rate of several fruits and vegetables affected by rapid elevation of temperature were carried out under simulated conditions, using an apparatus automated by microcomputer.1) Temperature of spinach packed in carton box, precooled at 5゜C or at 15゜C and transported under uninsulated condition elevated rapidly during transportation, and attained to ambient temperature at next morning. Rapid elevation of temperature in case of spinach packed in foam-plastic box was also observed. On the other hand, temperature of spinach transported under insulated condition covered by foam-rubber sheet maintained at low level below 10゜C. Changes in freshness of spinach at ambient temperature after transportation were not affected by precooling temperature.2) Carbon dioxide output and oxygen uptake of several fruits and vegetables increased rapidly to peak value with rapid elevation of temperature from 5゜C to 35゜C, and then decreased gradually to constant level at 35゜C. This excess acceleration of respiration rate was observed significantly at higher rate of temperature elevation. Little excess acceleration was observed in case of 10゜C elevation of temperature.3) From the results obtained above, it is considered that fruits and vegetables in transit at ambient temperature may not be necessary to precooled at extreme degree of low temperature such as 5゜C. In addition,elevation of temperature during transportation kept within 10゜C may be favorable for keeping quality of fruits and vegetables, judging from the standpoint of their physiological response.