F2+Fats+and+oils

= Fats and Oils =

F.2.1 Describe differences between saturated and unsaturated fat!!
Naturally occurring fats contain a mixture of saturated, mono- unsaturated (one unsaturated) and poly unsaturated fatty acid. ( Think about Alkane and Alkene) Top Saturated fatty acid, Bottom monosaturated 

examples of saturated and unsaturated fats:


 * ** Mono-unsaturated (olive, canola and peanut) **
 * ** Poly-unsaturated fats (safflower, sunflower, corn, fish, linoleic and linolenic) are liquids, **
 * ** Saturated fats (palm, coconut, lard, butter and shortening) are solids at room temperature. **

F. 2. 2 Predict the degree of crystallization (solidification) and melting point of fats and oils from their structure, and explain the relevance of this property in the home and in industry.
Crystallization:


 * ** Solid fats are more likely to be crystalline, more saturated and/or have longer fatty acid hydrocarbon chains. **

Melting point :
 * Melting point of fatty acid increases with increasing relative molecular mass
 * Degree of unsaturation
 *  more unsaturated fatty acids have lower melting point, since there are less crystalline, and it has 'kink' in chain, so it unable to pack closely which lead to low Van der Waal' force.
 * //Cis// and //Trans// isomers
 * //Cis fatty acids// the hydrogen atoms are on the same side of the carbon–carbon double bond have lower melting points than trans fatty acids
 * //Trans fatty acids// the hydrogen atoms are on opposite sides of the carbon–carbon double bond.
 * Fats and oils are chosen for cooking on the basis of their melting temperature.
 *  For example, cocoa butter melts at close to body temperature,
 * Or fats chosen for cake-making melt over a wide range of temperatures.

F. 2. 3 Deduce the stability of fats and oils from their structure. [[image:http://www.topnews.in/health/files/fat-heart.jpg align="right"]]

 * Saturated fats are more stable than unsaturated fats.
 * Because the carbon–carbon double bonds in unsaturated fats react with:
 * oxygen (auto-oxidation),
 * hydrogen (hydrogenation),
 *  light (photo-oxidation)
 * <span style="color: black; direction: ltr; margin-left: 0.375in; margin-top: 0in; unicode-bidi: embed; vertical-align: middle;">Enzymes/heat/water (hydrolysis).

F. 2. 4 Describe the process of hydrogenation of unsaturated fats.

 * <span style="color: black; direction: ltr; margin-left: 0.375in; margin-top: 0in; unicode-bidi: embed; vertical-align: middle;">The addition of hydrogen to the carbon–carbon double bond of a fatty acid:
 * <span style="color: black; direction: ltr; margin-bottom: 0in; margin-left: 0.375in; margin-top: 0in; unicode-bidi: embed; vertical-align: middle;">in the presence of heat (140–225ºC)
 * <span style="color: black; direction: ltr; margin-bottom: 0in; margin-left: 0.375in; margin-top: 0in; unicode-bidi: embed; vertical-align: middle;"> pressure
 * <span style="color: black; direction: ltr; margin-bottom: 0in; margin-left: 0.375in; margin-top: 0in; unicode-bidi: embed; vertical-align: middle;">Finely divided metal catalyst (Zn, Cu, Ni) increases the amount of saturation.

F. 2. 5 Discuss the advantages and disadvantages of hydrogenating fats and oils.

 * Advantages: || Disadvantages: ||
 * changes a liquid oil to a semi-solid or solid, to make the melting point of an unsaturated fat more like saturated fat || mono- and poly-unsaturated fats are healthier for the heart than saturated fats ||
 * decreases the rate of oxidation (stability increases with increasing saturation) || in partial hydrogenation, trans fatty acids can form ||
 * increases hardness || trans fatty acids are hard to metabolize, accumulate in fatty tissue, are difficult to excrete from the body, increase levels of LDL (bad) cholesterol and are a low-quality energy source. ||
 * controls the feel and plasticity (stiffness). ||  ||