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The aim of this study was to investigate the effect of encapsulation method on antioxidant properties of Hyssop (Hyssopus Officinalis L.) extract. The extracts of the Hyssop were obtained by ultrasound assisted techniques, and the amount of phenolic compounds was 117.43 ± 9.22 (mg of gallic acid per 100 g of extract). The antioxidant activity of extracts in concentrations of 100, 200, 300, and 400 ppm was measured using DPPH free radical scavenging method and compared with 100 ppm of TBHQ synthetic antioxidants. The results showed that by increasing in concentration of the extract, the antioxidant activity of the extract increased. The Lepidium perfoliatum seed gum and Orchis mascula were chosen as coating material. Encapsulation was performed by emulsion production method. The antioxidant effects of nanocapsules in oil during 40 days of storage at 60°C were measured, which increased the oxidation of oil over time. The lowest amount of oil oxidation during storage compared to control samples was observed in samples containing nano encapsulated Hyssop extract due to reducing in release rate of the extract during storage and more protection of the extract. The results of this study suggest that encapsulation is an effective way to increase the antioxidant activity of the extract and could be increased the shelf life of edible oils with natural antioxidants. [ABSTRACT FROM AUTHOR]

In this study, monolayer drying of kiwi slices was simulated by a laboratory-scale hot-air dryer. The drying process was carried out at three different temperatures of 50, 60, and 70°C. After the end of drying process, initially, the experimental drying data were fitted to the 11 well-known drying models. The results indicated that Two-term model gave better performance compared with other models to monitor the moisture ratio (with average R2 value equal .998). Also, this study used artificial neural network ( ANN) in order to feasibly predict dried kiwi slices moisture ratio ( y), based on the time and temperature drying inputs ( x1, x2). In order to do this research, two main activation functions called logsig and tanh, widely used in engineering calculations, were applied. The results revealed that, logsig activation function base on 13 neurons in first and second hidden layers were selected as the best configuration to predict the moisture ratio. This network was able to predict moisture ratio with R2 value .997. Furthermore, kiwi slice favorite is evaluated by sensory evaluation. In this test, sense qualities as color, aroma, flavor, appearance, and chew ability (tissue brittleness) are considered. [ABSTRACT FROM AUTHOR]

The effects of chitosan coating incorporated with eucalyptus essential oil and α-tocopherol on the quality of silver carp fillet during chilled storage (4 + 1°C) were examined over a period of 16 days. The control samples (without any coating), chitosan coating (CH), chitosan coating incorporated with eucalyptus essential oil (CH+EEO) and chitosan coating incorporated with eucalyptus essential oil and α-tocopherol (CH+EEO+α) were analyzed by chemical, microbiological and sensory characteristics. Results showed that, total viable counts, total psychrotrophic counts and total volatile basic nitrogen of CH+EEO and CH+EEO+α were significantly lower than control and CH ( P ≤ 0.05). Addition of α-tocopherol to EEO retarded lipid oxidation. According to the sensory analysis results, CH+EEO+α was acceptable even at the end of the 16-day storage. The results indicated that chitosan coating was improved extending of meat shelf life. Using eucalyptus essential oil and α-tocopherol increased its efficiency significantly. Practical Apllications Fresh fish are usually more perishable than most other muscle foods. Many attempts have been made to prevent the spoilage of fresh fish. To avoid the use of synthetic food additives, numerous studies are currently focused on using natural products to improve the quality of sea food products. The results of the present study report the efficacy of chitosan edible coating enriched with eucalyptus essential oil and α-tocopherol as a new natural preservative for developing the shelf life of silver carp fillets. [ABSTRACT FROM AUTHOR]

The effects of liposomal encapsulated and unencapsulated (0.3 and 0.5% w/w) thyme extract (TE) on the quality of silver carp (Hypophthalmichthys moltrix) mince during chilled storage (4 ± 1°C) were examined over a period of 15 days. The samples were analyzed by microbiological (total viable count, psychrotrophic count) and chemical (peroxide value and total volatile nitrogen) experiments. Also, the efficacy of the encapsulated extract in control in the population ofEschershia coliO157:H7 inoculated in silver carp mince was investigated. Results showed that the samples containing 0.5% of encapsulated thyme had fewer changes in peroxide value and total volatile nitrogen in comparison to other treatments (p< 0.05). Encapsulated thyme also could inhibit the growth of mesophilic and psychrotrophic bacteria in the samples compared to the control and the samples containing unencapsulated extract during the storage period. Moreover, 0.5% encapsulated TE reduced the population ofE. coliO157:H7 below the acceptable level (< 2) from Day 9 until the end of the storage period. In conclusion, the results obtained from this study suggest that liposomal encapsulation may help to obtain higher antimicrobial activity in lower TE concentrations in minced fish. [ABSTRACT FROM PUBLISHER]

The effect of extraction methods (ultrasound and supercritical fluid) and solvents (ethanol, ethanol/water (50:50) and water) on the phenolic compounds and antioxidant activities of celery ( A pium graveolens) extracts was evaluated to determine the most suitable extraction method for protective effects on stabilizing canola oil ( CAO) during thermal condition (24 h at 180 C). Ultrasound ethanol/water extract was found to have the highest phenols compounds (438.75 mg gallic acid equivalents/g sample) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl [ DPPH] and oxidative stability index 98.71 % and 7.1 h, respectively). Then, this extract was added to CAO. Peroxide value, carbonyl value, polar compound, acid value conjugated dienes value and color index were taken as parameters for evaluation of stabilization efficacy of the celery extract. Results from different parameters were in agreement with each other, suggesting higher efficiency of celery extracts followed by tertiary butylhydroquinone and control treated (without additives), respectively. Practical Applications Lipid peroxidation is responsible for the quality deterioration of vegetable oil, fats and other food systems. Thus, the use of antioxidants to minimize the oxidation of lipids in food materials is extensively practiced. Recently natural antioxidants have gained increased interest because natural food ingredients are safer than synthetic ones. The result of this study showed that celery extracts have antioxidant activity and it can replace synthetic antioxidant tertiary butylhydroquinone in canola oil. [ABSTRACT FROM AUTHOR]

The effects of methylcellulose (MC) coating enriched with Pimpinella affinis essential oil (PAO) on quality and shelf life of fresh silver carp fillets during refrigerated storage (4 ± 1C) were examined over a period of 16 days. MC solution (3%) and MC enriched with PAO (1.5% v/v concentration) were prepared for coating of the fish samples. The control and the treated fish samples were analyzed periodically for microbiological (total viable count), chemical (pH, thiobarbituric acid [TBA], total volatile basic nitrogen [TVB-N], free fatty acid [FFA] and pv) and sensory characteristics. According to results (pv, FFA, TBA, TVB-N, pH), color and odor on MC contain 1.5% PAO and have less change in comparison to other treatments (P < 0.05), and it could inhibit a total bacteria growth and psychrophilic counts of fillet. The results indicated that MC contains 1.5% PAO, a good antioxidant activity, so it can be used for fish preservation without any undesirable changes in antimicrobial and sensorial attributes. [ABSTRACT FROM AUTHOR]