Factors affecting the replacement of wooden harvesting bins with plastic equivalents for the New Zealand kiwifruit industry

The New Zealand Kiwifruit Industry is one of the biggest in the world. New Zealand grown kiwifruit is exported to more than 60 countries with Europe, Japan, Asia and U.S being the major markets. Currently, wooden bins are used for picking, handling and storing kiwifruit. Horticulture industries in many countries including the U.S, Europe, and Australia started using plastic harvesting bins over 40 years ago due to additional benefits of using plastic. However, this technology is still not put into practice in New Zealand mainly due to wood availability, familiarity with wooden bins and lack of knowledge reflecting the benefits of plastic harvesting bins. In this study, physical damage to kiwifruit in contact to different types of wooden and plastic harvesting bins was quantified and compared. The objective of the research was to indentify various physical damage mechanisms to kiwifruit and their relative significance during harvesting and storage. Mechanical damage was simulated as compression, abrasion and impact tests, conducted under laboratory conditions. The main finding of this research was that contact with wooden surfaces caused a significant amount of visible damage to kiwifruit, more so than any plastic surface. In terms of venting, 10mm vents in plastic showed least amount of damage. Compression on 10 mm plastic vents resulted in only 10 % fruit rejection , which was the minimum among all tests under ambient and coolstorage conditions. Almost all tests with wood resulted in 100% fruit rejection; this means that the whole bottom layered fruit would be rejected from a wooden bin. No significant differences were observed in percentage mass loss of fruit compressed on different wooden surfaces for both 10 and 25N firmness fruit under ambient and coolstorage conditions. This suggested that for wood, having flat or vented surface does not make a difference in percentage mass loss. It was found that impacting fruit on wooden and flat plastic surfaces caused about 30% fruit bruising, however, no bruising was observed in fruit impacted on vented plastic surfaces. It can be concluded that plastic bins are superior to wooden bins due to less fruit wastage and bruising. The research established that the initial investment of replacing a wooden harvesting with a plastic bin can be recovered within first 5 years. In addition, plastic bin would recover more than its cost by savings on less fruit rejection