The effects of pre-harvest treatments with hexanal formulation on selected post-harvest quality parameters of limequat (Citrofortunella floridana J.W.Ingram & H.E.Moore) fruits
Keywords:Enhanced freshness formulation, EFF, hexanal, limequat, pre-harvest
AbstractGenerally, limequat (Citrofortunella floridana J.W.Ingram & H.E.Moore) fruits have a relatively short shelf life at supermarket display temperatures (17-22oC). In some cases, shelf life can be as short as four days, after which surface discolouration becomes evident, along with shrivelling, and in many instances, the development of post-harvest diseases. Therefore, for maintenance of marketable quality, these three factors must be controlled. Pre-harvest treatments are known to positively affect the post-harvest quality of many commodities. Among these, treatment with hexanal has resulted in improved post-harvest quality maintenance because of its retarding effect on enzyme-driven cellular degradation. This study was conducted to observe the effect of pre-harvest treatments with hexanal on the length of the shelf life and the post-harvest quality of limequat fruits. Pre-harvest spray applications of 2% and 4% EFF (Enhanced Freshness Formulation), containing hexanal as the active ingredient, were made at weekly and biweekly intervals 30-days before the expected date of harvest. Pre-harvest spray treatments of EFF at 2% and 4% to trees of limequat resulted in the delay in the rate of colour change from green to yellow by an average of 7 days and 14 days, respectively, in harvested mature fruit. Senescent changes and other signs of deterioration including surface discolouration as brown patches, appeared on the fruit only after full colour change from green to yellow had occurred. Pre-harvest treatment also resulted in a reduction in the incidence of post-harvest diseases by up to 21 days during storage at 17-19oC / 90-95% RH. Thus, pre-harvest spray application had a marked effect on appearance by delaying both yellowing and shrivelling of the fruit, and consequently on marketability since appearance is one of the main factors determining acceptability in the marketplace.