steps during the distribution chain. The first link of the strawberry distribution chain consists of removing the field heat from the fruit as soon as possible after harvest, usually by forced air cooling. The importance of prompt precooling on
William Pelletier, Jeffrey K. Brecht, Maria Cecilia do Nascimento Nunes, and Jean-Pierre Émond
JoAnn Robbins and Patrick P. Moore
The effects of delayed precooling on fresh red raspberry fruit during storage was determined. Precooling was delayed for 0.5 to 12 hours, followed by cold storage for 8 days, with subsequent storage at 20C for 24 hours. Weight loss was greater with increasing delays of precooling. Fruit that lost more weight during the delay period lost less during the subsequent S-day storage at 0C. The exception was fruit held for 12 hours before precooling. Weight loss during the final 24 hours at 20C showed no pattern. Cumulative weight loss at the end of the storage treatments was similar regardless of delay of precooling. Fruit strength was reduced by any delay of precooling. The effect of delayed precooling on color was not consistent in the 2 years using different cultivars. The results indicate that fruit should be precooled as quickly as possible after harvest for long-distance fresh marketing.
Adolph J. Laiche Jr. and C. O. Box
‘Harson’ lily bulbs were precooled at 45 to 50°F for 0, 2, 4 and 6 weeks in damp peat (68% moisture) or dry peat (8% moisture) and then soaked for 2 hr in a 900 ppm solution of GA or tap water prior to forcing. Bulbs precooled in damp peat for 4 to 6 weeks had the shortest stems and earliest flowering. Four weeks precooling in damp peat hastened stem emergence and flowering but reduced flower no. as compared to those precooled 6 weeks in dry peat. Bulbs GA treated and precooled 2 weeks flowered about 4 weeks earlier without a decrease in flower no. compared with bulbs precooled for 0, 2, 4 and 6 weeks. Bulbs precooled 4 weeks in dry peat and treated with GA emerged and flowered as early as those precooled in damp peat for 4 weeks without GA or those in dry peat 6 weeks with or without GA. GA treatment hastened flowering similar to that caused by precooling in damp peat.
E. Chalutz, Mina Schiffmann-Nadel, J. Waks, and F. S. Lattar
Precooling at -2°C for 6 - 24 hrs prior to simulated ventilated shipment reduced weight loss of citrus fruit. Weight loss from the fruit was reduced as cooling rate increased. The difference in weight loss between precooled and control fruit was maintained during simulated shipment and after storage. Precooling the fruit to temp below 0°C could adversely affect its quality and should be avoided.
Donald E. Hudson and William H. Tietjen
Fruit of blueberry (Vaccinium corymbosum L.), precooled to 2°C, had 60–80% less decay than non-precooled berries when held for 24 hours at 21° following a 3-day simulated transit period at 10°. When precooled berries were held 48 hours at 21° following a 10-day simulated transit period at 2°, they had 37–46% less decay than non-precooled berries similarly handled.
Mark Sherman, Robert F. Kasmire, Kenneth D. Shuler, and Daniel A. Botts
Thorough precooling of bell peppers (Capsicum annuum L. cv. California Wonder) to 10°C (50°F) soon after harvest delayed, but did not prevent, soft rot decay caused by Erwinia carotovora (L. R. Jones) Holland. There was little weight loss and shrivel in any of the treatments. Inoculated peppers with intact or partial peduncles had better overall visual quality and were less decayed than peppers with no peduncles.
Todd J. Cavins and John M. Dole
Narcissus L. `Music Hall', N. `Tahiti', Tulipa L. `Couleur Cardinal', and T. `White Emperor' bulbs were precooled at 5 °C for 0 or 5 weeks and planted 15, 30, or 45 cm deep (from bulb base) into raised ground beds under 0%, 30%, or 60% shade. Plant growth was monitored for two consecutive years after planting. Precooling reduced the percentage of T. `White Emperor' that flowered but did not affect flowering percentage of the other cultivars. Precooling delayed anthesis in one or both years for all cultivars. The greatest percentage of bulbs flowered when planted 15 cm deep and the 45-cm planting depth reduced flowering percentage. Increasing planting depth delayed anthesis for all cultivars. Increasing shade increased stem lengths in one or both years for all cultivars, but did not influence flowering percentage. Perennialization was low for all cultivars regardless of treatment. Cultivar differences in perennialization occurred; in year 2 up to 30% of N. `Tahiti' bulbs flowered vs. 32% for `Music Hall' and up to 30% of T. `White Emperor' bulbs flowered vs. only 22% of `Couleur Cardinal'.
A. H. Bennett and John M. Wells
A new technique, termed hydraircooling, was evaluated for precooling fruit of peach (Prunus persica (L.) Batsch) packed in DU-ALL or similar type containers. Cooling rate was determined with respect to air and waterflow. Waterflow rates of 3.63 and 5.44 ml/minute were tested at each of 4 airflow rates (1070, 2140, 3210 and 4280 ml/second). Half-cooling times, with respect to airflow, ranged from 0.460 to 0.348 hour on top and 0.672 to 0.451 hour on the bottom of the container at 3.63 ml/minute waterflow. At the 5.44 ml/minute waterflow, respective half-cooling times ranged from 0.470 to 0.328 hour on top and 0.511 to 0.249 hour on the bottom. The peaches in these tests were 6.35 cm in diameter. In tests to compare hydraircooling with forced-air precooling, using 7 cm diameter peaches, respective half-cooling times were 0.433 hour compared to 0.516 hour on top and 0.523 hour compared to 0.731 hour on the bottom at an airflow of 2140 ml/second and a waterflow in the hydraircooler of 3.63 ml/minute. Cooling rate increased in relation to air and waterflow with the greater significance being obtained in relation to waterflow.
Charles Magee, Johnny Carter, and Clarence Johnson Jr
During the summer of 1988, a study was conducted to determine the effect of an inexpensive reusable styrofoam container on the percent weight loss in collards (bunch and head) after 30 days in a walk-in cooler. This container was designed and constructed for precooling, shipping, and storing fruits and vegetables. The insulated container was provided with a lid-mounted ice cavity that was removable and could be replaced through an access door without removing the lid. The ice cavity melted and was dispersed throughout the container onto the collards. The three treatments used in this study were (1) no top (2) top without ice, and (3) top with ice. Results indicated that both the bunches and heads responded similarly to treatments. The top with ice treatment significantly reduced percent weight loss when compared to the other treatments (top no ice and no top).
T. A. Prince, R. C. Herner, and A. A. De Hertogh
Flowering of ‘Kees Nelis’ (Tulipa gesneriana L.) tulip bulbs was not impaired after 4 weeks of storage at 17°C in either 3 or 5% oxygen. ‘Kees Nelis’ bulbs stored in air or 1% O2 for 4 or 6 weeks and ‘Prominence’ bulbs stored at any reduced O2 level for 4 or 6 weeks flowered unsatisfactorily. Bulbs specially precooled later in the forcing season yielded unsatisfactory flowering after storage at 17°C regardless of cultivar. Low O2 levels (1 to 5%) reduced the respiration rate of bulbs stored at 17°C for 6 weeks compared to bulbs stored in air. Storage of ‘Kees Nelis’ bulbs for 3 weeks in air with 5 ppm ethylene caused flower abortion upon forcing. Three or 5% O2 reduced ethylene-induced flower abortion during storage.