Preparation and evaluation of blended and interesterified oils

Anitha, Nagaraju (2009) Preparation and evaluation of blended and interesterified oils. PhD thesis, University of Mysore.

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Abstract

Vegetable oils are part of traditional diets all over the world. Triglycerides make up the majority of the lipids in edible fats/oils. The fatty acid composition of the edible oils has been one of the main focuses in defining nutritional value of dietary fats. Nutritional properties of dietary lipids are largely influenced by the nature of their constituent fatty acids, degree of unsaturation, distribution of fatty acid on triglyceride back bone and the composition of nonglyceride fraction of oil. Certain saturated fatty acids play an important role in increasing plasma cholesterol concentrations and determining the risk of coronary heart disease. In contrast, mono unsaturated fatty acids and polyunsaturated fatty acids have been shown to decrease the plasma cholesterol concentration in various clinical studies and various animal models. The majority of the reported adverse effects of fats and oils on health are related to their excessive consumption. The growing awareness on the impact of dietary saturated fats on cardiac problems is resulting in the changes in the types of the oils used in our diet. All the negative effects attributed to fats is slowly leading to great concerns and possible elimination of fat from diet. However, oils and fats are essential part of balanced diet, as they provide numerous components needed for maintaining our health. According to the Indian council of medical research, the desirable proportions of saturated, mono and polyunsaturated fatty acids in the dietary fats should be in the proportion of about 1:1:1. According to the American heart association, the optimum intake of fat for an adult is 30% of total calorie and the ratio of saturated/monounsaturated/polyunsaturated fatty acid 1:1:1, which was also endorsed by studies in India. Naturally available oils are unique in its composition. Careful analysis of edible oils available in India indicates an imbalance in their composition and is not in tune with recommendations made by nutritionists. Some of the commonly used edible oils in India are Coconut oil, Ground nut oil, Sunflower oil, Mustard oil. Coconut oil is characterized by high levels of medium chain fatty acids, mainly lauric acid and small amounts of capric, caprylic and caproic acid. It is deficient in essential fatty acids which needs to be supplemented. This can be achieved by blending Coconut oil with oil like ground nut oil containing essential fatty acids. Olive oil which is consumed in Synopsis  ix mediterranian regions is endowed with many health benefits due to the presence of phenolics. However olive oil is not in the main stream of edible oils in India due to its limited availability and high cost. Blending of olive oil with coconut oil may be a way of introducing it in Indian market at affordable cost and providing health benefits of olive oil in Indian population. However blending of two oils may not provide all the required benefits. They may need to be further modified by way of rearranging fatty acids in the triacylglycerol molecules of blended oil. Hence modification of oils and fats is one of the requirements in food processing industry that demands novel economic and green technologies. In this respect, tailor made vegetable oils with nutritionally beneficial structural triacylglycerols and altered physicochemical properties have a potential in the future market. Structured lipids are tailor made fats and oils with improved nutritional or physical properties. Recent Investigators have demonstrated that structured lipids have a desirable metabolic actions superior to the physically modified oils with identical composition but not subjected to interesterification reactions. In majority of the experiments reported in the literature, the oils containing medium chain triglycerides are interesterified with polyunsaturated fatty acid containing oils. Structured lipids of this type have been reported to have beneficial effects on a range of metabolic parameters including immune function, nitrogen balance and improved lipid clearance from the blood stream. This interesting observation need to be exploited to develop oils which can provide superior health benefits. To provide balanced edible oils to Indian population, the present study aims at the preparation and evaluation of coconut oil which is blended and interesterified with unsaturated oils like ground nut oil or olive oil.

Item Type:	Thesis (PhD)
Uncontrolled Keywords:	interesterified oils-; Physicochemical properties; Effct on-; Serum and Tissue lipids; Antioxidant enzymes; Platelet aggregation
Subjects:	600 Technology > 08 Food technology > 05 Processing and Engineering 600 Technology > 08 Food technology > 19 Lipids-oils/fats
Divisions:	Lipid Science and Traditional Foods
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	12 Mar 2010 09:55
Last Modified:	12 Mar 2010 09:55
URI:	http://ir.cftri.res.in/id/eprint/9381

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