Cooling trials with plastic tray pack nectarines in various containers
Studies were conducted on the effect of side venting pattems on the cooling rate of nectarines in several commercial containers, and in a container with a new experimental design. The location of vents had some effect on cooling rate, but the differences did not appear to be commercially important. Dividing the vent area into a large number of small openings substantially slowed room cooling (the cooling of containers by placing them in a cold room) without improving uniformity. Room cooling was speeded considerably when the side vent area was increased to about 6 per cent. However, further increases in the vent area only slightly speeded room cooling. The value of vent areas greater than 6 per cent, especially when located along top or bottom score lines, must be weighed against their potential weakening effect on the container. When forced-air cooling was used (the forcing of cold air through the container and around the fruit) the cooling time was directly related to vent area regardless of size and location. The design of the experimental container facilitated air circulation, resulting in only small differences in cooling time between the 3.8 and 5.6 per cent side vent openings. The use of this container design and the choice of container venting may depend upon the results of static stacking tests which were not included in these studies.