Evaluation of anti-fungal activity of chitosan and its effect on the moisture absorption and organoleptic characteristics of pistachio nuts

Abstract

Iran is one of the largest pistachio producers and exporter in the world. In case of improper storage the pistachio quality will drop down for proliferation of fungus and absorption of moist which causes tissue destruction, undesirable flavour in the product.The aim of this study is examination of anti-fungal activity of Chitosan and its impact on the organoleptic characteristics of pistachio nuts.Therefore, we coated the pistachios with acetic acid of 1% V/V, Chitosan in a concentration of 0.5%, 1% and 1.5% V/W. Acetic acid of 1% was used for coating to determine its antimicrobial effect on the pistachio.The coated pistachios were packed in polyethylene made bags and kept in a room with temperature (25-27 0C) for a six month period. During the storage, samples were examined every other week for total mold and yeast count, percent of Aspergillus development, moisture content and weight fluctuation and sensory evaluation. Experiments were performed in a factorial form in a completely randomized design. The results showed that Chitosan significantly (P0.05). Finally, Chitosan solution at 1% concentration was selected as the best treatment

Keywords

• antifungal activity
• chitosan
• moisture absorption
• organoleptic characteristics
• pistachio