Authors:S. Siddiqui, E. Kovács, J. Beczner, R.K. Goyal and F.C. Garg
The study was undertaken to increase the shelf-life of fruits of guava (Psidium guajava L. cultivar Banarsi Surkha). Uniform size and healthy fruits at green mature stage from winter season crop were exposed at atmospheric pressure to vapours of absolute ethanol and acetic acid for 2 h and hot water (vapour heat treatment) for 10 min. In the present investigation, only ethanol vapour treatment proved to be promising in enhancing the shelf-life of guava fruits, as other treatments showed phytotoxic effect. Ethanol treated fruits showed smaller weight loss and higher flesh firmness during storage. The activities of polygalacturonase, ß-galactosidase and cellulase were decreased by all the vapour treatments, however, ethanol was the most effective. It also reduced ethylene evolution and the contents of total soluble solids and ascorbic acid. All the vapour treatments could effectively decrease the mold colony forming units of surface microflora and eliminate coliforms. The results are discussed in relation to the mode of action of these vapours in delaying ripening of fruits.