There are a number of different varieties of lettuce including Iceburg, Cos, Italian, Oakleaf, Coral, Minuete, Radicchio and Endive. Lettuce is very perishable and wilts quickly following harvest from water loss unless it is pre-cooled quickly and packaged in Peakfresh and refrigerated. Russet spotting (brown edges) is induced by damaged lettuce and the presence of ethylene. Lettuce is easily damaged by freezing.
Packaging Method:
There are three proven methods using Peakfresh to extend freshness and shelf life. The first is to individually bag a head of lettuce. The second is to use a carton liner for 6-10 lettuce and fold the top over. Do not seal the carton liner top. The third method covers the export of lettuce to hot climates where temperature variations in refrigeration may occur or refrigeration is not available. To avoid unnecessary build up of moisture caused by temperature changes, oversized Peakfresh sheet is placed in the bottom of the carton, the lettuce loaded and a further oversized sheet of Peakfresh placed over the top of the lettuce. This method avoids sudden heat damage, but maintains humidity levels and limited control of ethylene gas produced by the lettuce. Using Sheet Peakfresh is recommended for sea freighting of heads of lettuce under refrigeration.
Bagged lettuce in has a transit and shelf life of around six weeks when sent to Antarctica and using sheet around five weeks when delivered to the Middle East. Lettuce must be packed dry with damaged outer leaves removed. Do not wash lettuce before packing.
Recommended Post Harvest Temperatures:
OºC (32ºF) not above 2ºC (36ºF) and 95% humidity.
IMPORTANT. Please read. All recommendations for the use of Peakfresh products are given in good faith and based on proven field experience. Packaging method storage temperatures and humidity levels, transit and destination conditions are factors likely to affect the performance of Peakfresh products and no liability for indirect or consequential damage can be accepted. We recommend that Peakfresh products be trialed under local conditions before introduction to large scale commercial applications.
