File Name: hydrogenation of fats and oils .zip
The lipid hypothesis states that eating saturated fats leads to elevated LDL Low Density Lipoprotein which is perceived to be bad cholesterol. This will result in coronary heart disease which is hardening and narrowing of arteries resulting in heart attack. Unhealthy fats where perceived to be saturated fats, healthy fats where perceived to be unsaturated fats.
In nutrition , biology , and chemistry , fat usually means any ester of fatty acids , or a mixture of such compounds ; most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides triple esters of glycerol , that are the main components of vegetable oils and of fatty tissue in animals;  or, even more narrowly, to triglycerides that are solid or semisolid at room temperature, thus excluding oils. The term may also be used more broadly as a synonym of lipid -- any substance of biological relevance, composed of carbon , hydrogen , or oxygen , that is insoluble in water but soluble in non-polar solvents. Fats are one of the three main macronutrient groups in human diet , along with carbohydrates and proteins ,   and the main components of common food products like milk , butter , tallow , lard , bacon , and cooking oils. They are a major and dense source of food energy for many animals and play important structural and metabolic functions, in most living beings, including energy storage, waterproofing, and thermal insulation. Dietary fats are also the carriers of some flavor and aroma ingredients and vitamins that are not water-soluble.
For many edible purposes and for some commercial applications it is desirable to produce solid fats. Many shortenings and margarines contain hydrogenated hardened oils as their major ingredients. The development of margarine and shortening products resulted from the invention of a successful method for converting low-melting unsaturated fatty acids and glycerides to higher-melting saturated products. The process consists of the addition of hydrogen in the presence of a catalyst to the double unsaturated bonds. Thus oleic or linoleic acid or their acid radicals in glycerides , which are normally liquid at room temperature, can be converted to stearic acid or the acid radical by the addition of hydrogen.
The supply and demand of edible oils and fats is briefly reviewed, and certain trends, relevant for the application of fat modification techniques, are noted. The effect of hydrogenation conditions on a number of selectivity aspects in hydrogenation with nickel catalysts is explained in terms of mass transport effects for hydrogen and triglycerides. The effect of selectivity on stability and melting behavior is also discussed. The limitations of the existing hydrogenation process with nickel are pointed out, and possible extensions by use of other catalysts, such as sulphur poisoned nickel, copper, and chromium complexes, are mentioned. Some technological aspects of the process are briefly reviewed. This is a preview of subscription content, access via your institution. Unilever Ltd.
Purchase Hydrogenation of Fats and Oils - 2nd Edition. Print Book & E-Book. ISBN ,
Advice service. Oils such as vegetable, olive, sunflower are liquids at room temperature. In the food industry, hydrogen is added to oils in a process called hydrogenation to make them more solid, or 'spreadable'. Hydrogenated oils can be sold directly as 'spreads', but are also used in the food industry in the manufacture of many foodstuffs such as biscuits and cakes.
Roslyn B. Alfin-Slater, Arthur F. Wells, Lilla Aftergood, Harry J. Deuel, Jr.
Food companies began using hydrogenated oil to help increase shelf life and save costs. Hydrogenation is a process in which a liquid unsaturated fat is turned into a solid fat by adding hydrogen. During this manufactured partially hydrogenated processing, a type of fat called trans fat is made. While small amounts of trans fats are found naturally in some foods, most trans fats in the diet come from these processed hydrogenated fats. Partially hydrogenated oils are most commonly found in foods that also have saturated fat , such as:. According to the U. Food and Drug Administration FDA , a company can label a food free of trans fats if the actual content is 0.
As in the first edition, discussion is not confined to vegetable oils, and the hydrogenation technique is considered in detail. The "why" as well as the "how" of hydrogenation are addressed. Written for both production staff who need advice on specific problems and development personnel who seek directions, if not solutions, the book offers direct practical advice along with explanations of why changes occur as they do. The glossary of technical terms contains a more detailed explanation of some features mentioned throughout the text.
Some vegetable oils were hydrogenated with scrap automobile catalyst SAC as a catalyst.
Hydrogenation of vegetable oils has been practiced since the discovery by Normann some 75 years ago and is the major chemical process in the fat and oil industry.Reply