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The quince fruit can be an alternative for producing healthy tea because it is a rich source of bioactive compounds. This study was conducted to evaluate the effects of heating (for 20, 40 and 60 min) on the bioactive compounds of quince and quality attributes its tisanes. To this aim, phenolic content of the treated sample (for 40 min according to sensory analysis) was evaluated by HPLC and antioxidant activity was measured using DPPH method. The analysis of sensory evaluation data demonstrated that the heating process significantly improved the color and taste of the quince tisanes. Thermal treatment (180°C) for 40 min had maximum acceptability. Although, results confirmed negative effects of the heating process on phenolic content, it showed an increase in antioxidant activity. The HPLC data displayed significant reduction in total amount of five identified phenolic compounds from 460.51 to 25.49 mg/25 g extract by heat treatment. In contrast the roasted sample exhibited lower IC50 (663.88 lg/ml) than the unprocessed sample (1098.66 lg/ml). Considering the elevated antioxidant activity achieved through the heating process, the quince tisane can be considered as a healthy beverage.

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Pistachio is one of the main export products of Iran and Iran is one of the largest producer and exporter of pistachio in the world. Unfavourable environmental conditions during storage, causes a sharp drop in quality of product through musty and toxin production, especially aflatoxin by Aspergillus flavus and Aspergillus parasiticus, Absorption of foreign odors and moisture, Tissue destruction of undesirable flavour. The aim of this study was to study the anti-fungal activity of chitosan and its effect on the organoleptic characteristics of pistachio nuts. Therefore, using acetic acid 1% V / V, chitosan concentrations of 0.5%, 1% and 1.5 % V/W was prepared and pistachios were coated by these solutions. Also acetic acid at concentration 1% without chitosan was used as a treatment for coating to determine the antimicrobial effect of acetic acid. The results showed that chitosan significantly (p <0.05) inhibited the growth of the Aspergillus and its effect was increased with increased concentration. Chitosan also prevented moisture absorption and weight change in pistachio nuts, while chitosan concentration showed no significant effect on moisture absorption and weight change of pistachio nuts. Chitosan 1.5% had a significant effect (p <0.05) on the flavour of pistachio, but other concentrations had no effect. However, chitosan in general had no significant effect (p <0.05) on color, texture and acceptability of pistachio nuts.