EVALUATION OF COATING MATERIALS AND PLANT EXTRACTS ON STORAGE LIFE AND QUALITY MAINTENANCE OF SWEET ORANGE (Citrus sinensis L.) AT HARAMAYA, ETHIOPIA

Abstract

Orange fruits have a relatively high post-harvest loss because of their inherent biological behavior and postharvest handling practices. High loss of orange in Ethiopia is partly associated with poor postharvest handling techniques. The experiment was carried out to assess the effects of coating materials and plant extracts on the shelf life and quality maintenance of orange fruit. Freshly harvested fruits of mature Valentia orange variety were dipped in different plant extracts and natural coating substances. The experiment was set in a completely randomized design with factorial preparation in three replications. The treatments consisted of a 5x3 factorial combination of plant extracts (Eucalyptus 25%, Lantana 25%, Rosemary 10%, Neem 20% and control) and coating treatments (bees wax 12%, Aloe debrana gel 100% and control). The experiment was conducted at Haramaya University during 2023 for 40-days, stored at room temperature. Different physico-chemical parameters and shelf life of fruit were assessed at interval of 5 days until 40th day. The result revealed that combination of neem leaf extract and beeswax coating proved to be the most effective in increasing shelf-life, lowering TSS/TA and weight loss, improve marketability, juice content, TA and AA. Slow increases of pH and weight loss were also observed on fruits treated with beeswax. The beeswax coating had significant effect than Aloe debrana gel on most of the parameters studied. Generally, coating of fruit with beeswax in combination with dipping in neem plant extract maintained high marketability acceptance and extended shelf life. Therefore, coating of fruits of Valentia orange variety with combination of neem leaf extract and beeswax and beeswax alone could have benefits to be used as alternative for management of postharvest loss of fruits under ambient storage condition of Haramaya and similar environments.