Post-harvest Preservation of Dessert Bananas Using Rapeseed and Olive Oil-based Wax in Côte d’Ivoire

Abstract

In Côte d'Ivoire, dessert bananas account for 8-10% of agricultural gross domestic product (GDP), 3-4% of national GDP and directly employ 11,000-12,000 people. It is the leading fresh fruit export, accounting for around 95% of production. This makes the country the leading African supplier to the European Union market. However, many losses, estimated at between 30% and 70%, due to export conditions and post-harvest diseases, have been noted on a regular basis. With the aim of proposing a solution to minimise these losses, a trial on the effectiveness of wax based on a proportional mixture of rapeseed and olive vegetable oil (100g/l) was carried out to provide solutions linked to the quality requirements of fruit for export. The aim of this study was to evaluate the effectiveness of different doses of wax (with or without fungicide) for better post-harvest preservation of dessert bananas. The experiments were carried out in a randomised complete block design with 9 treatments and 5 replications. Fruits of the 'Grande naine ' variety were treated either by spraying/or soaking. The fruit was kept in a cold room for 20 days before being removed and exposed to room temperature for 10 days. Parameters such as green life (GLS), fresh mass, pH, titratable acidity and crown rot disease were assessed every 5 days. The data collected was analysed using Statistica version 7.1 software. The results showed that treatments T1T (Fungicide + 5% rapeseed and olive wax applied by dipping) and T1P (Fungicide + 3% rapeseed and olive wax applied by spraying) were the most effective. These treatments maintained a very long DVV for up to 30 days, with no adverse effect on mass or firmness. In addition, the coating on the banana had no detrimental effect on the physicochemical change in the pulp of the treated fruit. On the other hand, the occurrence of anthracnose symptoms for treatments T2T (Fungicide + 7% rapeseed and olive wax applied by soaking) and T5T (Fungicide + 5% rapeseed and olive wax applied by soaking) was higher, with values of 100% and 80% respectively. The application of wax, either by soaking or by spraying, may be recommended in Côte d'Ivoire for the post-harvest preservation of dessert bananas.