Ultrasonic Analysis

Edible fats and oils play an important role in the human diet because of their characteristic nutritional, organoleptic, heat transfer and rheological properties 1. Ultrasonic analysis of edible fats and oils. Oils and fats constitute one of the three major classes of food constituents besides proteins and carbohydrates (Lawson, 1995). Effect of Heating on the Characteristics and Chemical Composition of Selected Frying Oils and Fats. By definition, a fat is solid at the temperature of interest, whilst oil is liquid. The chemical constituents of fats and oils are triglycerides, i.e. esters of glycerol and three fatty acid molecules. Ultrasonic analysis of edible fats and oils

In food chemistry and technology, the molecular structures of the

Researchers (Tynek et al., 2001; Cuesta et al., 1991) have found a relative loss of the C18:2 fatty acids and a decrease in the iodine value of oil after heating due to more intensive thermo-oxidative transformations that occur compared to heated oil containing food. The decrease in the iodine value can be attributed to the destruction of double bonds by oxidation, scission, and polymerization. According to previous studies (Orthoefer et al., 1996; Tyagi and Vasishtha, 1996; Choe and Min, 2007), the heat treatment causes the oxidative rancidity resulting in an increase in the free fatty acids. This is why heated and unheated fats and oils should be monitored by means of analysis, e.g., the FAC and IV indicating the degradation of the FAs. Usually many oils can be used for frying, e.g., palm oil, corn oil, cotton oil, soya oil, canola oil, sesame oil, and sunflower oil (Valenzuela et al., 2003). Several different oils are usually blended to get a healthy oil mixture. Therefore, the formulation should be low in its content of linoleic and linolenic acids, whereas it should contain a high level of natural antioxidants to be stable in the heating process. Effect of frying process on fatty acid composition and iodine value of selected vegetable oils and their

The frying industry is constantly seeking for new frying oils that are stable and impact desired characteristics to fried products. Thermal stability of the frying oil is related to the level of hydrogenation. The oxidative stability of the frying oil will increase with increased degree of hydrogenation. Thus, hydrogenated oils are widely used in the industry. However, during the hydrogenation process trans fatty acids are generated which, are associated with increased risk of hazards to human health. This fact has become a major concern for the use of hydrogenated oil in the fried food industry. Recently, as an alternative to hydrogenated frying oil, partially hydrogenated oils with less degree of un-saturation are increasingly adopted. Evaluation of Frying Oil Quality Using VIS/NIR Hyperspectral