Vaccum cooling and long distance transport test by truckwith Asparagus

Abstract

In order to study the transportation technique for Asparagus, vaccum cooling, packaging and long distance transportation by truck were discussed. Results were obtained as follows : 1. Vaccum cooling rate of Asparagus was slower than that of leaf vegetables such as lettuce and spinach. In addition, if the prewetting was not applied, temperature differences among each part of Asparagus were subject to be large.2. As for the temperature reduction at each part, the reduction at basal end was larger than that at any other parts. when the basal end was cooled down to 3°C, temperature at the center of spear became 6°C or higher, especially 10°C in the case of stretch package (Key H in Table 1).3. The temperature was reduced about 6. 3°C for each 1 % weight loss during vaccum cooling in the general.4. Weight losses of Asparagus during transportation tend to be larger by means of truck than by means of airplane in same packaging form, which depended on the difference of the required time for these transportations. Among vaccum cooled Asparagus, there was a 0.6 % weight loss at least in the case of stretch package (Key H) and a 2.3 % weight loss at most in the case of banded one (Key I).5. Young's modulus of Asparagus was measured after transportation. Young's modulus of non-prewetted Asparagus was smaller than that of non-precooled one in each packaging form. Significant differences in Young's modulus were not found among each packaging form, but in same packaging form, the modulus of prewetted one was higher than that of non-prewetted one.6. Total weight loss of Asparagus during vaccum cooling and transportation was the largest in the case of stretch package with holes (Key I).7. Significant differences in chemical ccmpositions such as ascorbic acid and reducing sugar content were not observed among each treatment.8. According to the result of sensory test, there were not any treatments blow grade 3 which was defined to be the limit of marketability; however, spoil in taste and softening of spear during vaccum cooling were pointed out.