ABSTRACT
Lipids contribute very signiŒcantly to the quality of almost all kinds of foods. They affect the structure of various raw materials and have a large impact on the nutritional value, safety, and the sensory properties of foods. They are the richest kind of energy source in the human diet, supply the organism with numerous substrates for the synthesis of biologically important metabolites and structures, and serve as a carrier of fat-soluble vitamins and other lipophilic substances needed in nutrition. However, they can also be a vehicle of harmful contaminants. They add their own attributes to different sensory properties of foods, and affect the rheological behavior of many products by having their characteristic structure and melting point and by interacting physically with other constituents. Furthermore, the products of enzymatic and chemical reactions of lipids contribute to the formation of pleasant or undesirable notes of color and ºavor. These effects are caused in different degrees by various natural fats differing in chemical and functional properties, as well as by novel, tailor-made lipids produced by applying biotechnological and chemical processes. The effect on food quality is related predominantly to the contents, distribution in the food matrix, chemical composition, and reactivity of the lipids, as
4.1 Introduction .................................................................................................... 71 4.2The Contents and Composition of Lipids in Foods ........................................ 72
4.2.1The Contents and Distribution ............................................................ 72 4.2.2Lipid Classes Affecting Food Quality ................................................ 73
4.2.2.1Structural Lipids and Depot Fats ......................................... 73 4.2.2.2 Fatty Acids ........................................................................... 74
4.3Lipids Affecting the Nutritional Value and Safety of Foods .......................... 74 4.3.1Nutritional BeneŒts ............................................................................. 74 4.3.2Food Lipids Posing Health Hazards ................................................... 75
4.4The Effects of Lipids on the Sensory Attributes of Foods ............................. 76 4.4.1 Introduction ........................................................................................ 76 4.4.2Lipids and the Color of Foods ............................................................ 77 4.4.3The Role of Lipids in Food Texture .................................................... 77 4.4.4Lipids and Food Flavor ....................................................................... 78
4.5Interactions of Lipids with Other Food Components ..................................... 79 References ................................................................................................................ 79
well as to their physical changes due to processing, and the interactions with other components. A very large asset in the activities aimed at increasing the role of lipids in improving the quality of food is the rapidly growing potential of analytical methods (Sacchi and Paolillo 2007).
