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ONPS2143

2010 Literature Review Assignment
ONPS2143 -Lipids in Food Science
2012 Literature Review Assignment

Introducti...
ONPS2143

2010 Literature Review Assignment

There are many methods available for the analysis of the lipids. The two meth...
ONPS2143

2010 Literature Review Assignment

body so keep safe while working with this soxhlet extractor. Soxhlet, F (1879...
ONPS2143

2010 Literature Review Assignment

Conclusion

The above discussion analyze that lipids are soluble in organic s...
ONPS2143

2010 Literature Review Assignment

References:
1. Laurence M. Harwood, Christopher J. Moody. Experimental organi...
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  1. 1. ONPS2143 2010 Literature Review Assignment ONPS2143 -Lipids in Food Science 2012 Literature Review Assignment Introduction In Food lipids are one of the major constituents and also a most important part for our diet and that has been proven in the number of researches. There have been a number of reasons for which lipids are very useful for our body and important to the diet. Lipids are considered as the one of the most important or major sources of energy and consists of the essential lipid nutrients. It is not always that there are benefits from the lipids but also there is problem because of this too if the lipid are consumed over the limit. (Laurence M. Harwood et al, 1989) Not all lipids but few specific lipids if consumed over the certain limit then it might be harmful for the health. For example cholesterol and saturated fats are harmful if consumed more than the limit. The physical characteristics of the food mainly determine by the amount of the lipid in the food. This is the reason the low fat alternatives of the number of food are very difficult to develop because with the reduction or removal of fat the physical characteristics of the food get lost. Some of the important properties of the foods include as the amount of total lipid concentration, which type of lipid present, physicochemical properties and structural organization of lipids within a food etc. Lipids are generally defined as the components that are soluble in the organic solvents. The Lipids are insoluble in water. In the lipid fraction of the food there is high complex mixture of the different molecules. The analysis of the lipids can be done with the different methods such as soxhlet extractor (William B. Jensen, 2007) and solvent extraction. Both methods are used to analyses the lipids in the food and both are very specific methods for the acids which are mainly soluble in organic solvent only. How much lipid concentration is available can be analyzed through the use of these mentioned methods. (Nielsen, S, 1994) The analysis can easily separate lipid components in food from water soluble components. This report analyze about the two different methods of lipid analysis based on the previous literature. Two different methods of Lipid Analysis Page 1 of 1
  2. 2. ONPS2143 2010 Literature Review Assignment There are many methods available for the analysis of the lipids. The two methods soxhlet extractor and solvent or liquid - liquid extraction methods are analyzed based on the earlier literature. The analysis is done such as: Soxhlet extractor – This analysis is done to analyze the concentration of the lipids in the food and also used for extracting the lipids from the solid material. (Soxhlet, F, 1879) The lipids are not dissolved in the water and other liquid solvent except the organic solvent so it is very use using the soxhlet extractor. Laurence M. Harwood states in his research that soxhlet extractor is very useful to separate the lipids from the food. Not only for food but also in other activities it can be used perfectly. (P. Giridhar et al, 2006) This methodology only works where there is the compound which has the limited solubility in the solvent. In this method the solid material or food which contains the desired component or lipids inside a thimble which is made of the thick filter paper. That thick filter paper made thimble is loaded in to the main chamber of the soxhlet extractor. Then this soxhlet extractor is placed on the above of the flask which contains the extraction solvent. And then the condenser is used in the soxhlet extractor for extracting the desired components as lipids from the material. The solvent is heated then and the vapor travels to the condense part and the desired components is separated from the solid material. Soxhlet extractor is generally used for the fast –food or can say as commercial foods to extract the fats from the food. Nielsen, S (1994) describes that the chemical process used for the extraction of the lipids from the food as using the soxhlet extractor for the fast foods because these foods have the highest amount of the lipids. This soxhlet extractor is not good for the foods where there is poor extraction of polar lipids, long time involved, large volumes of solvents, and hazards of boiling solvents. The accuracy of getting the concentration of the lipids or amounts of the lipids in the food is almost 95-98 percent because as the method use the condense process so in that case there is some chances of not getting the condense lipids from the food perfectly as there might be some components of the extracted material too. (William B. Jensen, 2007) As from the previous literature it can be explains that the precision of the extracted lipids have some issues as lipids are not 100 percent pure lipids extracted from the foods. As this method is totally equipment based in the laboratory so there is need to follow the instructions to carry out the extraction process and also there is need to maintain safety issues because the equipment is made of the glass and thick paper as well it uses the high temperature. (Laurence M. Harwood et al, 1989) Chemicals are harmful for the Page 2 of 1
  3. 3. ONPS2143 2010 Literature Review Assignment body so keep safe while working with this soxhlet extractor. Soxhlet, F (1879) itself explains in his research that safety is more important in this analysis. This method is suitable for both routine use and for the research too because this instrument also works automatically so very useful for the industry too. It signifies that soxhlet extractor is very useful for extracting the lipids concentration from the foods which have high amount of the lipids. Solvent or Liquid- Liquid extraction – The purpose of this analysis is to extract the compounds or separate the compounds which have the relative solubility in two different immiscible liquids. The immiscible liquids are water and organic solvent. It is generally used for separating the lipids from the water in the food. (Yoshinari Baba et al, 2002) It is an extraction of a substance from one liquid phase into another liquid phase. Liquid–liquid extraction is a basic technique in chemical laboratories, where it is performed using a separatory funnel. This type of process is commonly performed after a chemical reaction as part of the work-up. There are few processes used in the solvent extraction for different kind of lipid extraction in many ways such as Batch wise single stage extractions, multistage countercurrent continuous processes, extraction without chemical change, Ion pair extraction, (Danil de Namor et al, 1983) solvation mechanism and ion exchange mechanism etc. This method is applicable for the foods such as meat, milk, margarine, cookie, dairy cream which has highest fats inside it. The lipids concentration can be determine form the solvent extraction process from these foods. This method is most suitable for these kinds of foods because there is high amount of the water and the lipids are not soluble in the water easily so can be extracted easily. The accuracy issues in this method as the lipids are separated from the immiscible liquids and it might happen that the not all the lipids are separated from the liquid so the concentration of the lipids in the food can’t be tested accurately but it is 97-99 percent accurate. J. M. Sánchez explains that the accuracy is more than the other methods in this method lipid concentration measurement. There is not much issues in case of the precision of the measurement of the lipids in the foods mentioned above. (M. Filiz et al, 2006) As this method does not use the equipments so the safety problems are less but as because it uses the chemicals so the person who is doing the process should be keep safe with the chemicals. It is a method that is suitable for routine use in industry and also applicable to research too because this is very general process and can be used to extract the lipids in larger amount too. Page 3 of 1
  4. 4. ONPS2143 2010 Literature Review Assignment Conclusion The above discussion analyze that lipids are soluble in organic solvent but not in the water so easily separated from the water solvent in the food. The important methods are used for the lipid analysis such as soxhlet extractor and solvent extraction. Solvent extraction method is generally used method for isolating lipids from the foods and also determines the amount or concentration of lipids in the food. (J. M. Sánchez et al, 1999) Soxhlet extractor is used for isolating the lipids from the solid material and is a kind of laboratory apparatus. The previous literature states that lipids can be analyses with these methods and these lipids are very important for the health if are taken within the limit as required. This concludes that the lipids are important for health and the concentration of the lipids in the food can be analyzed using the different methods. Page 4 of 1
  5. 5. ONPS2143 2010 Literature Review Assignment References: 1. Laurence M. Harwood, Christopher J. Moody. Experimental organic chemistry: Principles and Practice (Illustrated edition ed.). 1989 pp. 122–125 2. Soxhlet, F. Die gewichtsanalytische Bestimmung des Milchfettes, Polytechnisches J. (Dingler's) 1879, 232, 461 3. The Origin of the Soxhlet Extractor, William B. Jensen Vol. 84 No. 12 December 2007 • Journal of Chemical Education. 4. Nielsen, S. Introduction to the Chemical Analysis of Foods; Jones and Bartlett: Boston, 1994; pp 183–191. 5. Danil de Namor, A.F.; T. Hill (1983). Journal of the Chemical Society, Faraday Transactions: 2713. 6. M. Filiz, N.A. Sayar and A.A. Sayar, Hydrometallurgy, 2006, 81, 167–173 7. Yoshinari Baba, Minako Iwakuma and Hideto Nagami, Ind. Eng. Chem. Res, 2002, 41, 5835– 5841 8. J. M. Sánchez, M. Hidalgo, M. Valiente and V. Salvadó, Solvent Extraction and Ion Exchange, 1999, 17, 455–474. 9. P. Giridhar, K.A. Venkatesan, T.G. Srinivasan and P.R. Vasudeva Rao, Hydrometallurgy, 2006, 81, 30–39. 10. K. Takeshita, K. Watanabe, Y. Nakano, M. Watanabe (2003). "Solvent extraction separation of Cd(II) and Zn(II) with the organophosphorus extractant D2EHPA and the aqueous nitrogendonor ligand TPEN". Hydrometallurgy 70: 63–71. Page 5 of 1

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