Edible hydrogenated fats

Double-bond migration often passes unnoticed, for unless tracers are employed, there may be no direct evidence remaining that migration has occurred. Nonetheless, the fact that it does occur can have a number of important consequences. Selective removal of cis homoconjugated dienes and trienes in natural oils, used to make edible hydrogenated fats, depends mainly on prior isomerization of multiple unsaturation into conjugation under hydrogenation conditions (J9). 

Nickel is a hard, silver-white metal used mainly for the production of stainless steel and for alloying with copper to produce cupronickels, the alloys used for nickel coins (which consist of about 25% Ni and 75% Cu). Cupronickels are slightly yellow but are whitened by the addition of small amounts of cobalt. Nickel is also used in nicad batteries and as a catalyst, especially for the addition of hydrogen to organic compounds, for example, in the manufacture of edible solid fats from vegetable oils (Section 14.5). Nickel s most stable oxidation state is +2, and the green color of aqueous solutions of nickel salts is due to the presence of [Ni(H20)6]2+ ions. 

Hydrogenation is a chemical process where liquid oils are converted to solid fats. In this process, hydrogen is added to oils in the presence of a catalyst. Inedible oils or less useful oils are converted to edible, hard fats by this process. For example, cotton oil is treated with hydrogen at about 500°C in the presence of a catalyst. The resultant hard fat is used for cooking. 

Chapter 4 presents the chemistry and technology of edible oil, fat, and wax processing including refining, recovery, crystallization, interesterification, and hydrogenation. The key oxidation reactions of lipids leading to quality deterioration of processed and unprocessed foods, and the mechanism of... 

Neatsfoot oil Sodium decyl sulfate fatliquor, textiles Sodium decyl sulfate fat-liquoring agent, leather Canola oil Paraffin, chlorinated Rapeseed (Brassica campestris) oil fats/oils, edible Hydrogenated menhaden oil fatting agent, cosmetics Dimethicone copolyol acetate 2-Hexyldecyl stearate... 

Nickel also is an important iadustrial catalyst. The most extensive use of nickel as a catalyst is ia the food iadustry ia connection with the hydrogenation or dehydrogenation of organic compounds to produce edible fats and oils (see Fats and FATTY oils). 

Cocoa butter substitutes and equivalents differ greatly with respect to their method of manufacture, source of fats, and functionaHty they are produced by several physical and chemical processes (17,18). Cocoa butter substitutes are produced from lauric acid fats such as coconut, palm, and palm kernel oils by fractionation and hydrogenation from domestic fats such as soy, com, and cotton seed oils by selective hydrogenation or from palm kernel stearines by fractionation. Cocoa butter equivalents can be produced from palm kernel oil and other specialty fats such as shea and ilHpe by fractional crystallization from glycerol and selected fatty acids by direct chemical synthesis or from edible beef tallow by acetone crystallization. 

Hydrogenation of fats and edible oils H2 + unsaturated oil Ni Saturated oil... 

In this chapter, we report just a few selected examples of heterogeneous catalytic systems for the esterification of fatty acids and for the simultaneous esterification and transesterification of acidic oils and fats, and we discuss the use of selective hydrogenation as a tool for the production of high-quality biodiesel from non-edible raw materials. 

Accurate determination of the amount of solid fat in edible fats and oils is an essential requirement for process control in food industry during hydrogenation, interesterification and blending. Moreover, important physical properties, such as hardness, heat resistance, mouth-feel and flavor release, can be predicted via measurements of solid fat content at different temperatures using low resolution (low-field) NMR. 

The nickel catalyst used in the hydrogenation of natural oils and edible fats is a special example of a catalyst which is transported in a protected state. In this case, the catalyst is protected by encapsulation in solid fat. The fat melts when the catalyst is introduced into the reactor, so releasing the active phase. Particular care must be taken to control the temperature during the transport and handling of this material. 

Fig. 34.26. Effects of adding hardstock (<5 IV) to broaden plastic range working temperatures of two base stocks. (From Hastert, R. C., "Cost/Quality/Health Three Pillars of Hydrogenation," in World Conference Proceedings Edible Fats and Oils Processing Basic Principles and Modern Practices, D. R. Erickson (Ed.), pp. 142-152, American Oil Chemists Society, Champaign, IL, 1990. With permission.)...

Hydrogenation of edible fats and oils 1900s Food production unsaturated fatty acids — partially saturated acids Ni on a support... 

The largest use of industrial hydrogen is in ammonia synthesis, in the catalytic hydrogenation of unsaturated liquid vegetable oils to solid, edible fats (margarine), and in the manufacture of bulk organic chemicals, particularly methanol, by the Oxo Process using a cobalt catalyst ... 

The most important chemical reactions for triglycerides (fats and edible oils) are hydrolysis, methanolysis, and interesterification. The other reactions, such as hydrogenation, isomerization, polymerization, and autoxidation that are primarily relevant to the processing of edible oils and fats are also discussed in this section. 

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