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Background and Objectives: Kefiran (Kef) is a water-soluble polysaccharide that can form transparent film however, it is brittle. Therefore, in order to improve the mechanical properties of kefiran film, a mixture with other polymers can be offered. The expansion of mixed systems can propose kefiran and polyvinyl alcohol (PVOH) as a new composite film. Materials and Methods: Solutions of 20 gram per liter kef and 40 gram per liter of PVOH were prepared. A mixture of film-forming solutions of different ratios of Kef/PVOH (100/0, 68/32, 50/50, 32/68) was prepared. In this study, different experiments including the physical properties (thickness, moisture content, and film solubility in water), water vapor permeability, and mechanical properties (tensile strength, elongation at break, puncture strength, and puncture deformation) of composite films as well as the rheological properties of film forming solutions were investigated. Results: The results of physical properties such as thickness, moisture content, solubility in water and mechanical properties such as tensile strength, elongation at break, puncture deformation, puncture strength and water vapor permeability indicated that the mechanical properties, thickness and solubility in water increase with increase in PVOH content however, moisture content and water vapor permeability decrease. Rheological characterization of different film forming solutions exhibited Newtonian fluid behavior. Conclusions: These results contribute to the establishment of an approach to optimize films’ composition based on the interactions between polymers, aiming at improving the properties of polysaccharide-based films. Keywords: Kefiran, Polyvinyl alcohol, Physical properties, Mechanical properties, Rheological properties

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Background and Objectives: Canola oil is very low in saturated fatty acid (~8 %), which makes it suitable for application as dressing for salad. Canola oil is liquid, thus its application in the production of margarine and shortening is limited. The present study provides information about the effects of monoacylglycerols (MAG) as the structuring agent on physical, microstructure and rheological properties of canola oil.
Materials and Methods: Canola oil was added 0.5, 3.0 and 5.0% MAGs. Fatty acid composition, iodine value (IV), slip melting point (SMP), solid fat content (SFC), rheological properties (viscose, elastic and complex moduli, complex viscosity and tand) and its microstructure by polarized light microscopy (PLM) were evaluated.
Results: MAGs at 0.5% concentration, did not affect the saturated fatty acid (SFA) content; however, at 3 or 5% concentrations, SFA content increased (P< 0.05). MAGs increased solid fat content (SFC) of fats proportional to MAG content. At 0.5% concentration, MAGs had no effect on SMP, but at higher concentrations, SMP increased with MAGs concentration. With the increase of MAGs concentration, the induction period of crystallization decreased and crystallization rate increased at all temperatures. In spite of the decrease of tand  by MAGs addition, samples containing higher MAG concentration had higher viscose, elastic and complex moduli and complex viscosity. PLM images indicated that MAG addition resulted in an increased hardness of canola oil.
Conclusions: Canola oil structured with MAGs, can find its application in the production of liquid margarines and shortenings suitable for the use in bakery.

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Background and Objectives: Use of aloe vera gel in dairy industries is important for increasing quality of dairy products. In the present study, effects of aloe vera gel with inulin and whey powder on survival of probiotic bacteria, rheological and sensory characteristics of yogurt were investigated.
Materials and Methods: Low-fat (1.5%) probiotic yogurts were prepared from pasteurized milks, 1% of starters and 2% combinations of Lactobacillus acidophilus with Bifidobacterium animalis at 40 °C and pH 4.4. Probiotic yogurts mixed with aloe vera gels at 0, 5, 10, 15 and 20% were stored seven days at 4 ^oC. Since the probiotic yogurt with 10% of aloe vera gel included the best sensory scores compared to other aloe vera gel concentrations after seven days of storage at 4 ^oC, this formulation was mixed with inulin at 0.5, 1 and 1.5% (w/w) or whey powder at 5, 10 and 15% (w/w). 
Results: Sensory evaluations showed that the probiotic yogurt with 10% of aloe vera gel and 1.5% of inulin included the highest scores of flavor, texture, aroma, color and acceptance within the samples after similar storage conditions. The probiotic yogurt with 10% of aloe vera gel and 1.5% of inulin included the highest survival of Lactobacillus acidophilus and Bifidobacterium animalis, while controls (with no aloe vera gels) showed the lowest survival rates of Lactobacillus acidophilus and Bifidobacterium animalis. Apparent viscosity and serum separation of probiotic yogurt with 10% of aloe vera gel and 1.5% of inulin respectively increased three times and decreased to less than 4%, compared to controls and whey samples at similar shear rates and storage times.
The pH decrease of probiotic yogurt with 10% of aloe vera gel and 1.5% of inulin was much slower than those of the control and whey samples during storage, including no serum separations during storage.
Conclusions: Aloe vera gel and inulin improved viability of probiotic bacteria and quality of yogurt samples during storage.