Efficacy of hexanal as a potential preservative of papaya (carica papaya l.) fruit.

Abstract

Fruits are rich in vitamins and antioxidants that are required in our daily diets. Papaya fruit for instance, is rich in pro-vitamin A and vitamin C that provide humans with a protective effect against cancer and other health challenges associated with the scavenge harmful oxygen-free radicals. The preservation of papaya is therefore very important to ensure a sustained health benefit supplied by this fruit. However, huge post-harvest losses, estimated above 40% have been reported due to quick ripening and softening of Papaya. The objective of this study was to determine the effects of hexanal as a potential organic compound for use to enhance the postharvest shelf life of papaya in Kenya. Hexanal is a volatile component of many plant tissues that occurs in traces in plants like cucumber, beans and grasses. Experiments were done using a liquid formulation of hexanal (hereinafter referred to as Enhanced Freshness Formulation, EFF) applied as a pre-harvest spray or postharvest dip on mature papaya fruits. Experiments were conducted using two concentrations of hexanal on volume by volume (v/v) basis at 1% and 2% v/v with a plain water treatment as a control and, applied to papaya fruits at two timings of 2.5 and 5 minutes in two Agro-ecological zone II (Meru) and IV (Machakos). Laboratory analyses we conducted at Jomo Kenyatta University of Agriculture and Technology (JKUAT). The parameters tested include Papaya firmness, peel and pulp colour, % cumulative weight loss, respiration rates, amounts of ethylene evolved, Total Titratable Acidity (TTA), Total Soluble Solids (TSS), Vitamin C and Beta-carotene.