: Edible oil is oxidized during processing and storage via autoxidation and photosensitized oxidation, in which triplet oxygen (3O2) and singlet oxygen (1O2) react with the oil, respectively. Autoxidation of oils requires radical forms of acylglycerols, whereas photosensitized oxidation does not require lipid radicals since 1O2 reacts directly with double bonds. Lipid hydroperoxides formed by 3O2 are conjugated dienes, whereas 1O2 produces both conjugated and nonconjugated dienes. The hydroperoxides are decomposed to produce off-flavor compounds and the oil quality decreases. Autoxidation of oil is accelerated by the presence of free fatty acids, mono- and diacylglycerols, metals such as iron, and thermally oxidized compounds. Chlorophylls and phenolic compounds decrease the autoxidation of oil in the dark, and carotenoids, tocopherols, and phospholipids demonstrate both antioxidant and prooxidant activity depending on the oil system. In photosensitized oxidation chlorophyll acts as a photosensitizer for the formation of 1O2; however, carotenoids and tocopherols decrease the oxidation through 1O2 quenching. Temperature, light, oxygen concentration, oil processing, and fatty acid composition also affect the oxidative stability of edible oil.

Mechanisms and Factors for Edible Oil Oxidation

Preface to the First Edition. Preface to the Second Edition. Contributors. List of Abbreviations. 1 Production and Trade of Vegetable Oils ( Frank D. Gunstone ). 1.1 Extraction, refining and processing. 1.2 Vegetable oils: Production, consumption and trade. 1.3 Some topical issues. 2 Palm Oil ( Siew Wai Lin ). 2.1 Introduction. 2.2 Composition and properties of palm oil and fractions. 2.3 Physical characteristics of palm oil products. 2.4 Minor components of palm oil products. 2.5 Food applications of palm oil products. 2.5.1 Cooking/frying oil. 2.6 Nutritional aspects of palm oil. 2.7 Sustainable palm oil. 2.8 Conclusions. 3 Soybean Oil ( Tong Wang ). 3.1 Introduction. 3.2 Composition of soybean and soybean oil. 3.3 Recovery and refining of soybean oil. 3.4 Oil composition modification by processing and biotechnology. 3.5 Physical properties of soybean oil. 3.6 Oxidation evaluation of soybean oil. 3.7 Nutritional properties of soybean oil. 3.8 Food uses of soybean oil. 4 Canola/Rapeseed Oil ( Roman Przybylski ). 4.1 Introduction. 4.2 Composition. 4.3 Physical and chemical properties. 4.4 Major food uses. 4.5 Conclusion and outlook. 5 Sunflower Oil ( Maria A. Grompone ). 5.1 Introduction. 5.2 Sunflower oil from different types of seed. 5.3 Physical and chemical properties. 5.4 Melting properties and thermal behaviour. 5.5 Extraction and processing of sunflower oil. 5.6 Modified properties of sunflower oil. 5.7 Oxidative stability of commercial sunflower oils. 5.8 Food uses of different sunflower oil types. 5.9 Frying use of commercial sunflower oil types. 6 The Lauric (Coconut and Palm Kernel) Oils ( Ibrahim Nuzul Amri ). 6.1 Introduction. 6.2 Coconut oil. 6.3 Palm kernel oil. 6.4 Processing. 6.5 Food uses. 6.6 Health aspects. 7 Cottonseed Oil ( Michael K. Dowd ). 7.1 Introduction. 7.2 History. 7.3 Seed composition. 7.4 Oil composition. 7.5 Chemical and physical properties of cottonseed oil. 7.6 Processing. 7.7 Cottonseed oil uses. 7.8 Co-product uses. 8 Groundnut (Peanut) Oil ( Lisa L. Dean, Jack P. Davis, and Timothy H. Sanders ). 8.1 Peanut production, history, and oil extraction. 8.2 Oil uses. 8.3 Composition of groundnut oil. 8.4 Chemical and physical characteristics of groundnut oil. 8.5 Health issues. 9 Olive Oil ( Dimitrios Boskou ). 9.1 Introduction. 9.2 Extraction of olive oil from olives. 9.3 Olive oil composition. 9.4 Effect of processing olives on the composition of virgin olive oils. 9.5 Refining and modification. 9.6 Hardening and interesterification. 9.7 Quality, genuineness and regulations. 9.8 Consumption and culinary applications. 10 Corn Oil ( Robert A. Moreau ). 10.1 Composition of corn oil. 10.2 Properties of corn oil. 10.3 Major food uses of corn oil. 10.4 Conclusions. 11 Minor and Speciality Oils ( S. Prakash Kochhar ). 11.1 Introduction. 11.2 Sesame seed oil. 11.3 Rice bran oil. 11.4 Flaxseed (linseed and linola) oil. 11.5 Safflower oil. 11.6 Argan kernel oil. 11.7 Avocado oil. 11.8 Camelina seed oil. 11.9 Grape seed oil. 11.10 Pumpkin seed oil. 11.11 Sea buckthorn oil. 11.12 Cocoa butter and CBE. 11.13 Oils containing a-linolenic acid (GLA) and stearidonic acid (SDA). 11.14 Tree nut oils. Useful Websites. Index.

http://health120years.com/cn/pdf/hd_Vegetable.Oils.pdf

Vegetable Oils in Food Technology: Composition, Properties, and Uses

Some historical facts on and botanical descriptions of sesame are given. Some flavor studies of raw and roasted sesame seeds and oils are described. Composition and some usages are also briefly reported. Sesame has long been regarded in the Orient as a health food which increases energy and prevents aging. Sesame oil has been known empirically as a cooking oil which is highly resistant to oxidative deterioration in comparison with other edible oils. Until recently there were no scientific studies to elucidate these interesting aspects of sesame seed and oil, but the author and members of his group initiated studies on the chemical elucidation of antioxidative principles of sesame seed and oil, and extensively investigated the antiaging effect of sesame. Presence of various new antioxidative lignan phenol compounds in sesame seed and oil is described. Sesaminol has been identified as a new antioxidative principle in raw sesame salad oil. The mechanism of the superior antioxidative activity of roas...

Shyi-Liang Shyu

Papers

Oxidative stability of sesame oil prepared from sesame seed with different roasting temperatures