Drying is one of the conservation methods of food that reduces moisture through the simultaneous transfer of heat and mass. In this study, the drying kinetics of Biodegradable film based on Carrageenan and using microwave was investigated as a new, fast and relatively inexpensive method and it was introduced as the most suitable mathematical model for describing drying kinetics. For this purpose, the prepared films were dried using microwave oven at 350, 500, 750 and 900 W. Also, 10 mathematical models were fitted to test data and their fitting quality was analyzed. The fitting quality of the proposed models was evaluated based on the parameters of the coefficient of explanation (R2), square mean square error (RMSE) of the square (χ 2). Comparison between different models showed that the Midley model could be the most suitable model for estimating moisture variations and describing the film drying behavior. The highest effective moisture penetration coefficient was also obtained at a power of 900 watts of 41. 7 × 10-4 and the lowest effective moisture penetration coefficient at 350 watts was found to be 2. 78-10. 5-5. The results showed that microwave power has an important effect on drying rate and drying time is decreased by increasing the dryer power. The initial drying rate at 900 watts 9. 8 g/min and it was 4. 3 g/min at 350 watts. The longest drying time was observed at 350 watts which lasted 425 minutes. Also, the drying time of films with this method was significantly reduced by 97% compared to the conventional method (at 25° C warm air).

Edible films and coatings are a thin layer of material that used on the surface and between different layers of nutrients. Biopolymers such as polysaccharides, proteins, lipids and their mixtures are used for the preparation of the edible films and coatings. Due to consumers demand for access to high quality materials and their concern because of the problems caused by the use of artificial preservatives, as well as environmental concerns arising from the accumulation of synthetic polymers, the idea of using Biodegradable biopolymers as a replacement for the plastic packaging was strong. Efficiency and functional properties of edible films and coatings is dependent on intrinsic properties of ingredients of films, namely, biopolymers, plasticizer and other additives. The useful properties of edible films and coatings are capability of eating and biodegradation of them. Some properties of edible film sand coatings, such as preventing moisture transport and volatiles out of food, selective throughput oxygen and carbon dioxide, delaying surface dehydration, tissue changes, barrier against fat sand oils transports, increase nutritional value, preventing dripping, microbial growth and rancidity, Maintaining the quality of Aquatic and their products against physical damage caused by their transportation, increase the shelf life of them. For industrial use, more scientific studies are needed to determine the mechanisms of the film formation from biopolymers for optimizing their properties. Biodegradable compounds used in this study for aquatic coating and their effects on maintaining the quality of fish and their action mechanism has been investigated.

In order to improve the properties of the starch Biodegradable films, three components were manipulated: citric acid, carboxy methyl cellulose (CMC) and nanoclay, and the effect of each of these ingredients on the morphological properties and roughness values of the films, as well as their homogeneity were investigated. Afterwards, the effect of nanoclay concentration on the moisture permeability of these films was investigated. AFM results indicated that the starch -CMC biocomposites and starch -CMC- nanoclay bionanocomposites had the lowest and highest roughness values, respectively. Results of the moisture adsorption test indicated that by increasing the nanoclay contents, moisture absorption of the films decreased. The films containing 7% nanoclay showed the lowest moisture absorption value (14.78%). However, according to the results of contact angle test, surface hydrophobisity of the films decreased by an increase in nanoclay contents.

Objective-The objective of the present study was to assess effect of propolis in combination with chitosan biofilm on excisional wounds. Design-Experimental Study. Animals-Male healthy Wistar rats. Procedures-Sixty-four rats were randomized into four groups of 16 rats each. Group I: Animals with wounds treated with 0. 9% saline solution. Group II: Animals with wounds were dressed with chitosan biofilm. Group III: Animals with wounds were treated topically with propolis and Group IV: Animals with wounds were treated topically with propolis and dressed with chitosan biofilm. Wound size was measured on 6, 9, 12, 15, 18 and 21days after surgery. Histological studies were performed on three time points of 7, 14 and 21 days post-wounding. Results-Planimetric studies and quantitative histological studies and mean rank of the qualitative studies demonstrated that there was significant difference (p<0. 05) between group IV and other groups. Conclusion and clinical relevance-It was concluded that the propolis with chitosan biofilm had a reproducible wound healing potential in excisional wounds in rats.

In the present study, a polymer was produced with the aim of food packing (especially meat) to inform the consumers from corruption stages of food corruption based on color of food pack and in addition to be Biodegradable. For this purpose, the Biodegradable films based on carrageenan in combination with red cabbage extract (Brassica oleaceae) prepared, after producing the films, their functional properties, including tensile strength and strength, solubility, water vapor permeability, microstructures were investigated using the FTIR test. Then, the relationship between the stages of corruption in Rainbow trout fillets (Oncorhynchus mykiss) and the color changes of packed film investigated for 48 hours at room temperature (in order to expedite corruption) condition. The PH, TVB-N and colorimetric performed in every 6 hrs intervals. The changes in color of the polymer determined at each stage of maintenance. According to the tests, the results indicated that carrageenan film containing cabbage extract, at first is colorless then after packaging the food, its color change which is in accordance with the corruption stage in fish packed. The TVB-N and pH changes extended and the color of the smoky film became dark. These symptoms could be used as a corruption index to inform the consumer about the quality and freshness of the packed fish. Therefore, according to the results of this study, the carrageenan film containing cabbage extract can be used as an indicator of fish corruption and other meat food.

ABSTRACT: In this study, an edible film is prepared using Mentha piperita essential oil (MPEO) plasticized by sorbitol and glycerol in cassava starch matrix by the solution intercalation process. The effects of MPEO addition on the color, and antimicrobial activity (Staphylococcus aureus and Escherichia coli), as well as the barrier properties of active films were investigated. MPEO was incorporated into cassava starch Biodegradable films at different level (1-3%, w/w). A low level of MPEO can obviously increased the water vapor permeability (WVP) of cassava starch/MPEO films. When the MPEO contents varied from 0-3% w/w, the lightness (L, value) decreased from 95. 63 to 89. 17 while the a* value increased from 0. 15 to 0. 82. The cassava film showed antimicrobial properties against S. aureus and E. coli by using agar diffusion method. These findings showed that Mentha piperita essential oil has a good potential to be added to cassava to make antimicrobial coating or film for food and non-food packaging.