Pg. 31-33 A preliminary study on the changes of epicuticular wax layer of Litchi (Cv. Mauritius) with respect to commercial packing line operations

All plant surfaces are covered by epicuticular wax that plays an important role in plant defense mechanisms. A scanning electron microscopy study was carried out as a preliminary investigation to observe the changes of the litchi epicuticular layers during handling and packing line practices. Although micro cracking was observed in mature fruit, it was more prominent in commercial sulfur dioxide fumigated fruit. In addition, rough handling during packing contributed to more micro cracking.

Summary:

• The study investigates how the epicuticular wax layer of litchi fruit (Cv. Mauritius) changes during commercial packing line operations using scanning electron microscopy (SEM).
• Epicuticular wax is important for plant defense and moisture retention in fruit.
• Micro cracking of the wax layer was observed on mature litchi fruit, with more severe micro cracking on fruit treated with sulfur dioxide fumigation.
• Rough handling during packing, such as fruit drops of 15 cm and brushing, caused increased micro cracking and wax layer damage.
• Micro cracking facilitates water loss from the fruit pericarp and may promote fungal infections, contributing to post-harvest decay and reduced shelf life.
• The sulfur dioxide fumigation process intensifies micro cracking compared to non-fumigated fruit.
• Careful handling and minimizing impacts during packing are essential to reduce wax layer damage and maintain fruit quality.
• The study plans to continue and expand in the next season (2004-05) to assess the impact of picking and transport practices on wax layer integrity.
• Understanding wax layer changes is critical because moisture loss and decay directly affect the fruit’s shelf life and marketability.
• The study highlights the need for optimizing packing lines to reduce physical damage and improve post-harvest preservation.