Determination of primary lipid oxidation products in cooking oils /
Determination of primary lipid oxidation products in cooking oils /
Section C2; Joel Javate; Anna Belen Ignacio-Alensuela; Mari-Ann B. Bringas; Dolores V. Viliran.
- Fairview, Quezon City: Department of Biochemistry, FEU-NRMF, 2013.
- 51 pages: illustration, tables, photos; 28 cm.
Includes appendices and bibliographical references.
Abstract: Present medical knowledge advocate the replacement of dietary saturated fats with polyunsaturated fatty acids to decrease the risk of cardiovascular diseases. PUFA-rich foods are therefore recommended Vegetable Oils used for cooking contain mostly PUFA. However, PUFA easily undergo lipid peroxidation by different processes like heating, which yields to the production of different products, such as hydroperoxides, which are said to be absorbed and metabolized in the body. Now, there is growing concern about the possible negative health effects from the intake of oxidized lipids. Little is also known about the degree of lipid peroxidation in such products. This study generally aims to measure the content of primary lipid oxidation products in five types of cooking oils available locally. Statistical data obtained was also used to determine if there is a significant correlation between the number of times heating and the Peroxide Value (PV) of vegetable oils. Five types of vegetable cooking oils were purchased in a local grocery stores. The content of primary lipid oxidation products were measured as peroxide value via iodometric titration. Samples measured were fresh, once heated, twice heated, and thrice heated for each type oil, using temperature (225oC) and time (25 minutes) resembling conditions typically used during cooking. Initially there is a large variation in the peroxide values among the untreated cooking oils with the palm oil having the largest at 4.1meg/kg and the coconut lauric oil having the least at 0.62 meg/kg. A steadily increasing level of peroxide content was noted after three rounds of heating, with values from 1.3 to 5.3 to 7.2 meg/kg and 0.62 to 5.3 meg/kg for palm oil, canola oil and coconut Lauri coil, respectively. In contrast, the soy oil and corn oil exhibited an initial decrease in peroxide level up to the second treatment, before returning to 80% of the initial untreated peroxide values by the third heating, with values of 4.1 to 3.3 meg/kg and 4.0 to 3.3 meg/kg accordingly. High temperature heating, dependent on frequency or duration of heating causes an increase in the peroxide value of some of the tested cooking oils particularly palm oil, canola oil and coconut lauric oil. However, this was not observed on the soya oil and corn oil. The product observed to have the greatest peroxide value upon the third heating was the canola oil.
Thesis - Department of Biochemistry & Nutrition
cooking oil
lipid peroxidation
saturated fatty acids
polyunsaturated fatty acids
hydroperoxide
M BIO 2013 0007
Includes appendices and bibliographical references.
Abstract: Present medical knowledge advocate the replacement of dietary saturated fats with polyunsaturated fatty acids to decrease the risk of cardiovascular diseases. PUFA-rich foods are therefore recommended Vegetable Oils used for cooking contain mostly PUFA. However, PUFA easily undergo lipid peroxidation by different processes like heating, which yields to the production of different products, such as hydroperoxides, which are said to be absorbed and metabolized in the body. Now, there is growing concern about the possible negative health effects from the intake of oxidized lipids. Little is also known about the degree of lipid peroxidation in such products. This study generally aims to measure the content of primary lipid oxidation products in five types of cooking oils available locally. Statistical data obtained was also used to determine if there is a significant correlation between the number of times heating and the Peroxide Value (PV) of vegetable oils. Five types of vegetable cooking oils were purchased in a local grocery stores. The content of primary lipid oxidation products were measured as peroxide value via iodometric titration. Samples measured were fresh, once heated, twice heated, and thrice heated for each type oil, using temperature (225oC) and time (25 minutes) resembling conditions typically used during cooking. Initially there is a large variation in the peroxide values among the untreated cooking oils with the palm oil having the largest at 4.1meg/kg and the coconut lauric oil having the least at 0.62 meg/kg. A steadily increasing level of peroxide content was noted after three rounds of heating, with values from 1.3 to 5.3 to 7.2 meg/kg and 0.62 to 5.3 meg/kg for palm oil, canola oil and coconut Lauri coil, respectively. In contrast, the soy oil and corn oil exhibited an initial decrease in peroxide level up to the second treatment, before returning to 80% of the initial untreated peroxide values by the third heating, with values of 4.1 to 3.3 meg/kg and 4.0 to 3.3 meg/kg accordingly. High temperature heating, dependent on frequency or duration of heating causes an increase in the peroxide value of some of the tested cooking oils particularly palm oil, canola oil and coconut lauric oil. However, this was not observed on the soya oil and corn oil. The product observed to have the greatest peroxide value upon the third heating was the canola oil.
Thesis - Department of Biochemistry & Nutrition
cooking oil
lipid peroxidation
saturated fatty acids
polyunsaturated fatty acids
hydroperoxide
M BIO 2013 0007
