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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: Shortenings are fats used mainly in the formulation of bakery, confectionery, dairy, and frying products. The aim of this study was to assess the physicochemical properties and trans fatty acid (TFA) content of shortenings produced in Iran.
Materials and Methods: Samples of 15 shortening brands produced in Iran (summer of 2016) were collected and characterized for their physicochemical properties.
Results: Iranian shortenings contained 0.21-15.54% TFA and 40.08-59.54% saturated fatty acids. The iodine value of Iranian shortenings was between 40.84 and 73.32. Lovibond yellow and red color indices of the samples were 2.1-13.6 and 28-70.4, respectively. The induction period of oxidation at 110°C (IP₁₁₀) of the samples was between 10.03 and 44.02 h. The slip melting point of the shortenings was between 42.5 and 49.3°C. Solid fat content of Iranian shortenings was 40.6-75.0% at 10°C, 24.2-59.5% at 20°C, 11.4-36.4% at 30°C, 7.8-27.3% at 35°C, and 3.1-17.4% at 40°C. Free fatty acid (FFA) content of shortenings ranged from 0.02 to 0.92%, and peroxide value was between 1.0 and 3.0 meq/kg.
Conclusions: Compared to the national standard for the specification of shortenings, 20.0% of samples had TFA content higher than the standard level (5%). Additionally, 13.3% of samples did not meet the standard limits of lauric acid content, 46.7% had FFA contents above and 53.3% showed IP₁₁₀ below the standard level. Accordingly, efficient control protocols should be established by the authorities to assure the production of shortenings with the standard properties.