Fats serve both as energy sources for the body, and as stores for energy in excess of what the body needs immediately. The rate of hydrogenation depends on the following factors. Fats and oils 9599% 14% glycerol deriavatives glycerol free fatty acids etc. Fats are solid at room temperature and contain saturated long chain fatty acids 6. Chemical and physical properties of lipids processing and. Fats and oils are example of lipids and are composed largely of triglycerides with great importance in food systems, and they are formed by esters of a molecule of glycerol and three fatty acid molecules. Physical properties of oils and mixtures of oils springerlink.
It focuses on fundamental aspects of the crystallization and transformation of fats employed in real food systems, through describing the use of important examples, such. The quality of cookie primarily relies upon the functionality of fats and oils in cookie system which ultimately is combined result of their physical, chemical, and rheological properties. Jul 27, 2017 the physical properties of lipids give them an essential role in influencing the texture, appearance and healthfulness of the foods we eat 2. Milk fat and cocoa butter are the two main forms of fat used in chocolate manufacture to provide these properties beckett, 2009. Triglycerides and fatty acid composition formed from glycerol and. Every oil is different, and with different molecular structures comes different chemical properties.
Hydrogenation, interesterification, fractionation, and blending are distinct processes that can be applied to modify the physical or chemical properties of fats and oils in order to improve their. Fats and oils are very important for every human body. Chemical and physical properties of lipids processing. However, there has been a continued shift from food to industrial consumption, particularly in biodiesel.
Fats and oils structure triglyceride3 fatty acids attached to a glycerol backbone various fatty acids within the tg slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Physical and chemical properties of crude oils and their. It focuses on fundamental aspects of the crystallization and transformation of fats employed in real food systems, through describing the use of important examples, such as cocoa butter, palm oil and palm mid. Presentations ppt, key, pdf logging in or signing up. While fats and oils are not soluble in water, other chemical compounds are only soluble in fats. The number of carbon and structure will largely define the chemical and physical properties of the oil. Aug 04, 2018 physical properties of fats and oil 1. Physicochemical, rheological and functional properties of fats and oils in relation to cookie quality. Lipids are a distinct group of compounds, including oils, waxes, steroids, fats and similar compounds that are very much connected by their physical property rather than their chemical property. Rapeseed oil exhibited a higher viscosity than canola, corn and soybean oils. Fats and oils can participate in a variety of chemical reactionsfor example, because triglycerides are esters, they can be hydrolyzed in the presence of an acid, a base, or specific enzymes known as lipases. Fats and oils are triesters of glycerol with saturated arid unsaturated fatty acids. Chocolate manufacturing process generally follows the common steps.
Nov 01, 2017 on the whole, the fatty acid profile of fats and oils, the presence of excess fatoil, and calcium content mainly dictate the appearance, melting, rheology, and microstructure of calcium soaps. This chapter covers the fundamentals and looks at recent research work on these three properties. Physical properties of oil specific gravitythe specific gravity of a substance is a comparison of its density to that of water. Many of these fatsoluble compounds are responsible for foods flavor and even vitamin content. Oils and fats important for storing chemical energy in living things. Their reactions are those of ester groups in triplicate and carboncarbon double bonds.
This degree of unsaturation determines to a large extent the ultimate use of the fat. Influence of fat and oil type on the yield, physico. The sources of fats and oils include edible vegetable oils, palm oils, industrial oils, animal fats, and marine oils. The physical properties of lipids give them an essential role in influencing the texture, appearance and healthfulness of the foods we eat 2. Lipids are a group of compounds which are differentiated by their feature of solubility in nonpolar solvents and insolubility in water. This can be determined by the peroxide value of fatsoils. They are readily hydrolysed by heating with acids or alkalies or superheated steam. Aug 16, 20 the different lipid species vary significantly with respect to their chemical and physical properties, their absorption, metabolism, and physiological activities. Including fat in food allows for maximum flavor and a wider range of nutritional content. Most of the physical properties of crude oils such as a. The minor components include mono and diglycerides, free fatty acids, phosphatides, sterols, fatsoluble vitamins, tocopherols, pigments, waxes, and fatty alcohols.
Together, they present the more important available data on this versatile chemical compound. The term lipids describes compounds such as fats, waxes, phospholipids, oils and other similar compounds. The different lipid species vary significantly with respect to their chemical and physical properties, their absorption, metabolism, and physiological activities. For this, the crystallization, the melting point, the viscosity, the refractive index, the density, the solubility. Their distinct properties can be used as criteria in predicting the condition and stability of fog deposits. Thus, the food science industry has developed a number of criteria by which to measure and evaluate the physical properties of lipids 2. For an understanding of the place of fats and oils in the diet and in the arts, some elementary knowledge of their chemical and physical properties is essential.
Hydrogenation hydrogenation is a reaction used to optimize the properties of fats and oils prepared for specific uses. A free powerpoint ppt presentation displayed as a flash slide show on id. Fatty acids contribute from 94 to 96 percent of the total weight of various fats and oils. Chemical properties palm oil fatty acid triglyceride. This can be determined by the peroxide value of fats oils. Triglycerides non glycerol deriavatives phospholipids sterols pigments hydrocarbons antioxidants etc. Each gram of fat when burned or metabolized releases about 9 food calories 37 kj 8. The main difference between fats and oils is that, fats are usually derived from animals, whereas oils are usually derived from plants. Physicochemical, rheological and functional properties of. Ppt acids, esters and fats powerpoint presentation. The free fatty acid content of crude oil varies widely based on the source. Physical properties of fats, oils, and emulsifiers.
Effects of some major fats and oils such as butter, bakery fat. By definition, lipids include any compound created by living organisms that resists reaction with water, including fats, hormones, oils and membranes. As volatile oil oils are responsible for the essence or odour of the plant they are also known as essential oils. Contrary to what you might expect, pure fats and oils are colorless, odorless, and tasteless. Nonetheless, the extraction method depends, among other factors, on the kind of material to. Volatile or essential oils, as their name implies, are volatile in steam. Ppt acids, esters and fats powerpoint presentation free. Before then, oil was primarily derived from animal fats. Any color or taste is due to association with other foreign substances. Further, they may be classified according to their degree of unsaturation as measured by their ability to absorb iodine at the double bonds.
The chemical properties of crude oils vary in relation to changes in. Study of the chemical composition of essential oils by gas. The introduction of vegetable oils into the american food industry began in the early 1900s. Chemical properties and introduction this booklet is the second in a series, the first being physical properties of glycerine and its solutions, published in 1963. Lipids serve many important roles, including energy storage, insulation, carrying. A fundamental understanding of the physical properties of fats, oils, and emulsifiers is essential to help the food processing industry meet consumer needs for quality foods with improved nutritional properties at a minimal cost. Milk is composed of protein, fats, carbohydrates, vitamins, and minerals. Because of their preponderant weight in the glyceride molecules and also because they comprise the reactive portion of the molecules, the fatty acids influence greatly both the physical and chemical character of glycerides. The properties evaluated were physical appearance, percent. The book also focuses on the current main concerns of the food industry regarding oils and fats use, including. Physical and chemical characteristics of oils, fats, and waxes, champaign, illinois, aocs press, 2006.
These are acids occurring in natural triglycerides and are monocarboxylic acids. Chemical analysis of fats and oils is done using procedures 100150 years old, but the modern lipid analysis started by introduction of gasliquid chromatography, and 20 years later of highperformance. Ppt volatile oils powerpoint presentation free to view. Chemical and physical properties of palm oil and palm kernel oil. Volatile oils evaporate on exposure to air at ordinary temperature and are the odorous constituents. They are secreted in oil cells, in secretion ducts or cavities or in glandular hairs. One of the significant things about glycerine is the.
More information is available for palm oil than for the other two. Fatty acids are basically the primary derivative of lipids. Major fats and oils industry overview chemical economics. Fats and oils with higher oleic to palmitic acid ratio have higher soap yield. Table 11 common fatty acids types of triesters triesters triglycerides 3 carboxylic acids react with. Food scientists, product development technologists, and food processors will be interested in this overview of both the fundamentals of fat crystallization and the. Also, it avoids oil heating or the use of sophisticated equipment. They differ entirely in both chemical and physical properties from fixed oils. Proteins consist of balanced negative and positive charges, which allow it to be soluble in milk. Chapter 8 lipids fats and oils the fatty acids in a triglyceride molecule are usually not all the same. Study of the chemical composition of essential oils by gas chromatography 309 organic solvent extraction or straight distillation as water steam has a lower cost compared to organic solvents. Fat, any substance of plant or animal origin that is nonvolatile, insoluble in water, and oily or greasy to the touch. Physical properties of fats in food fats in food technology. Food applications account for the major share about threefourths of the worldwide consumption of fats and oils.
The properties of mixtures of the oils also are considered, especially mixtures of palm and palm kernel oils in which a eutectic interaction occurs. This can be directly related to the contribution of saturated fatty acids noureddini et al. Unesco eolss sample chapters food quality and standards vol. Most people think lipid is just another term for fat, but lipids are actually an entire class of molecules. Fats are triglycerides that are solids at room temp. The yellow color of butter or is due to the presence of plant pigments carotene and xanthophyll. Jan, 2009 fats and oils structure triglyceride3 fatty acids attached to a glycerol backbone various fatty acids within the tg slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Chemical properties of fats and oils 1 acrolein test fats and oils contain glycerol so.
Hydrolysis it is the reaction of water with a substance such as fats. Fats are usually solid at ordinary temperatures, such as 25 c 77 f, but they begin to liquefy at somewhat higher temperatures. Chemical properties of lipids authorstream presentation. Amirah nurul hidayah nurul nadiah introduction oleochemicals are chemicals derived from plant and animal fats sources to produce oleochemical plant product. Nov 02, 2019 freshly prepared fats are colorless, odorless and tasteless. Fats are broken down in the healthy body to release their constituents, glycerol and fatty acids. Lipids serve many important roles, including energy storage, insulation, carrying messages between cells and forming cellular membranes. Fats and oils may be divided into animal and vegetable fats according to source. Fatty acids are composed of long hydrocarbon chains terminated by carboxylic acid groups. Oils are liquids at 20c, they contain higher proportion of unsaturated fatty acids 5.
Understanding rancidity of nutritional lipids rancidity is a natural process affecting oils. Fats and oils are totally different from each other. Influence of fat and oil type on the yield, physicochemical. Iii food lipids jan pokorny, jana dostalova encyclopedia of life support systems eolss fats are very rich in transmonoenoic fatty acids. On the whole, the fatty acid profile of fats and oils, the presence of excess fatoil, and calcium content mainly dictate the appearance, melting, rheology, and microstructure of calcium soaps. They contain even number of c atoms majority of fatty acids are those containing 16 and. Chemical and physical properties of carbohydrates 963. Sincere efforts of researchers are underway to understand the functionality of different fats and oils in relation to cookie quality. A ester of fatty acids and saturated hydrocarbon chains. It is intended for use by consumers, nutritionists, dieticians, physicians, food technologists, food industry representatives, students, teachers, and others having an interest in dietary fats and oils. Pdf physicochemical, rheological and functional properties. Oct 15, 2016 sincere efforts of researchers are underway to understand the functionality of different fats and oils in relation to cookie quality.
Palm oil palm oil has a balanced fatty acid composition in which the level of saturated fatty acids is almost equal to that of the unsaturated fatty acids. The main components of edible fats and oils are triglycerides. The main objective of this study was to compare the yield, physicochemical properties, and microstructure of laboratoryprepared fat, oil, and grease fog deposits produced from various fats and oils. The characteristic colors, odors, and flavors that we associate with some of them are imparted by foreign substances that are lipid soluble and have been absorbed by these lipids.
341 377 1026 1149 500 1049 1117 409 1552 1480 1548 1482 167 1490 1339 410 1294 654 53 629 483 140 85 512 1229 512 623 1006 94 352 882 299 418