Effect of Temperature on Shelf Stability of Soybean-corn Oil

Effect of Temperature on Shelf Stability of Soybean-corn Oil STUDY OF EFFECT OF TEMPERATURE ON SHELF STABILITY OF SOYBEAN-CORN OIL BLENDS. Atul Thakkar*, Jayshree Parikh** Abstract Soybean oil because of certain advantages is cultivated on large scale in recent years in India particularly in M.P, U.P, and part of Maharashtra. Soybean oil meal is rich in protein and the oil has ready outlet in vanaspati manufacture with the possibility, that it may be utilized as edible oil. The direct use of soybean oil for deep frying purpose has certain limitation as it contains significant amount of linolenic acid i.e. about 6.8 %. These polyunsaturated acids made the soybean oil unstable even under ambient conditions. Secondly the consumers do not have liking of the fishy flavor of the oil during deep-frying. Significant improvement in shelf life and thermal stability and flavor reduction can be achieved by lowering the linolenate content of soybean oil by blending in different proportions with corn oil. Corn oil widely used as an all purpose cooking oil and margarine because of the unique flavor it attributes and because it is more stable to oxidation than linolenate containing oil such soybean oil. Corn oil has milder taste and less expensive than most other types of vegetable oils. In present study to improve the stability and yet retain fluidity the soybean oil is blended with more stable corn oil thereby reducing linolenic acid content. The thermal stability for all the blends is studied by determining their Physico-chemical properties and fatty acid composition using standard methods. KEYWODS Soybean oil, corn oil, Thermal stability. INTRODUCTION Oils rich in Monosaturated fatty acid are gaining more importance these days due to their specific advantages over other oils. They are more stable towards oxidative changes over polyunsaturated fatty acid rich oils and hence prove to be better choice for frying or cooking application. Polyunsaturated fatty acid rich oils are more prone to oxidative changes, and hence promote oxidation in both food and non-food products, although important from health point of view. Thus while selecting oil or fat one has to consider both aspects that-oil should not be too much saturated and unsaturated as well. In fact as per latest guidelines of WHO/Japanese Heart Association the ideal ratio of SAFA: MUFA: PUFA should be 1:1.5:1.In order to derive maximum benefits from oil it is advised to consume a mixture of oils in order to maintain a balance between the fatty acids, and possible to keep cholesterol level in control. Now-a-days a number of blended oils are available in the market. For instance, blends of rice bran and sunflower oils. Soyabean oil is rich in protein but direct use of soybean oil has some limitation as it contains linolenic acid and it becomes unstable even under ambient conditions. To increase stability of soybean oil linolenic acid content must be reduce it can be done by changing fatty acid compositon this is possible by blending with more stable oils compare to soybean oil. In soybean oil linolenic acid is oxidized twice as quickly as linoleic acid and produces short chain aldehydes with flavor that are even stronger and less acceptable than those produced from linoleic acid, due to this odor of oil change. It can be used after one or two frying. It is the most saleable oil in india. Corn oil contains a significant amount of ubiquinone and high amounts of alpha and gamma tocopherols (vitamin E) that protect it from oxidative rancidity. It has good sensory qualities for use as salad and cooking oil. Corn oil is highly digestible and provides energy and Essential Fatty Acids (EFA). Linoleic acid is a dietary essential that is necessary for integrity of the skin, cell membranes, the immune system, and for synthesis of icosanoids. Icosanoids are necessary for reproductive, cardiovascular, renal and gastrointestinal functions and resistance to disease. Corn oil is highly effective food oil for lowering serum cholesterol. The use of corn oil to contribute to PUFA intake of 10% in the diet would be beneficial to heart health. It is rich in linoleic acid one of the three fatty acids . Corn oil beyond food and consumer product replacing petroleum in many industrial applications it is use as biofuel. Use of corn oil as a biodiesel is increases and for this purpose investment in cultivation of corn oil is increases not only in India but in Global states . It is used in pharmaceutical, cosmetic industries,paper, textiles, plastics, baked goods, candies, soups and mixes. It is also used as skin soother and softener. MATERIAL AND MEHOD Chemicals used A wide variety of chemicals were used in the experiments which are listed below. Acetic acid ,Acetone , Carbon tetrachloride,ethyl alcohol, HCl, Glacial acetic acid (All S.D.Fine Chemicals); Methanol, Chloroform, BF3-methanol solution (Qualigens); Hexane Heptane (HPLC grade, Qualigens); Wijs Solution (Merck Grade); isopropyl alcohol (China). Before using these solvents, their expiry was checked and these were stored properly. Reagens Used Sodium hydroxide Sodium thiosulphate Sodium sulphate Potassium iodide Sodium chloride,15% potassium iodide solution(15 gm of potassium iodide dissolve in 100 ml of water), potassium dichromate (All Qualigens). Before using these reagents their expiry was checked and was stored properly. Indicators Phenolphthalein (Qualigens) :-It was used by dissolving 1gm of phenolphthalein in alcohol. Starch (Qualigens):-Starch prepared by dissolving 1gm of soluble starch in 200ml distilled water and boil for few seconds. These indicators were prepared freshly as per the requirement of test. To observe proper colour changes during titration. Raw Material Soybean oil and Corn oil were purchased from market package of 1 liter. Before analysis, manufacturing and expiry date was checked properly. Before starting analysis, the colour and odor of these oils were checked. Methods Iodine value Iodine value is a measure of the degree of unsaturation in oil. It is constant for particular oil or fat. Iodine value is useful parameter in studying oxidative rancidity of oils since higher the unsaturation the greater the possibility of the oils to go rancid. This is the most important test to determine stability of oils. Peroxide value Rancidity is brought about by the action of air on the oil which is oxidative rancidity, where in, the fat takes up oxygen with the formation of peroxides. Peroxide value is the peroxide content in the oil.Procedure for determination for Peroxide value test was used from AOCS method. Free fatty acid value Free fatty acids are usually presents in oils along with the triglycerides. It increases during storage. It is keeping quality of oil; therefore the free fatty acid content generally increases on storage. This is most important test to find out quality of oils. This test performed according to the AOCS method. Fatty acid composition To find out fatty acid composition of oils gas chromatographic method is used because fatty acid evaluated in GC only it give prominent result. In this method oils first has to convert into methyl esters and then injected into the GC. Prepared sample seal in dry GC vial and kept in refrigerator before injection. Test performs as per the method of AOCS. The five major fatty acids in soybean oil are palmitate, stearate, oleate, linolenate, and linoleate. The fatty acids differ in the number of carbon and hydrogen atoms they contains, which causes differences in the nutritional value of each and their influence on the characteristics of food products. It show change in percentages when blend with other oils. All these tests were performed simultaneously. This study was followed by Thermal stability. In thermal stability study the sample was kept in oven which was set at 60oC. This stability analysis has been done continuously for seven days. For the thermal stability blends were prepared in the proportions given as in table 1. Pure oils were taken as reference. 250ml of sample taken in the 500 ml beakers, it was labeled properly. The beakers were not closed. Then the beakers placed in the preheated oven at 60oC for 6 hr. Then the samples were taken out, cooled at room temperature and analyzed for iodine value, free fatty acid content and peroxide value using AOCS methods. Then the samples were allowed to remain overnight at room temperature in a closed shelf. Next day the samples were again kept inside preheated oven for 6hr. followed by testing as above. Thermal stability testing was done continuously for seven days i.e.in all for 42 hours. Table 1: Ratio of blends and symbols used Table 2: Thermal stability: Iodine value. Table 3: Thermal stability: free fatty acid content. Table 4: Thermal stability: Peroxide value. Table 5: Results of Fatty acid composition (at 60Â °C for 42 hours) RESULT AND DISCUSSION The characteristics and fatty acid composition of oils used in the study are given in tables (from Table 2 to 5). All the oils were used fresh. During the storage studies at room temperature a small but steady rise in free fatty acid content and peroxide value and fall in iodine value was observed in all blends. In Shelf Stability (at room temperature) upto our 42 hours study Iodine value for pure soybean oil is ranging from (134.1 to 129.5), and Soybean oil,Corn oil composition ranging from (127.2 to 120.8), (120.7 to 115.8), (115.3 to 112.9), (108.1 to 104.9), (101.8 to 93.5) for pure corn oil (95.6 to 89.4). (Table 02, Figure 01). All these values indicate decrease in values of blends at high range compared to the pure oils. Decrease in iodine value may be due to the polymerization. Peroxide values in Shelf Stability (at room temperature) upto our 42 hours study for pure soybean oil is ranging from (3.1 to 7.2), and Soybean oil ,Corn oil composition Peroxide value ranging from (2.1 to 7.0), (1.9 to 6.9), (1.2 to 7.2), (0.9 to 7.5), (0.6 to 7.8) for pure corn oil (0.3 to 6.5) (Table 04, Figure 02). Free fatty acid content in Shelf Stability (at room temperature) upto our 42 hours study for pure soybean oil is ranging from (0.14 to 0.30), and Soybean oil ,Corn oil composition Free fatty acid value ranging from (0.15 to 0.34), (0.17 to 0.31), (0.18 to 0.30), (0.20 to 0.31), (0.21 to 0.32) for pure corn oil (0.25 to 0.33) (Table 03, Figure 03). The changes in these values may be due to oxidation which increases the free fatty acid content and peroxide value whereas decreases iodine value through marginally. The increase in peroxide value in the blend of soybean oil as the concentration of other oil increases indicates the increasing oxidative stability of blend as c ompare to other oil. The rate of decrease in peroxide value for soybean oil (Table 3) is very high as compared with corn oil.. This may be due to the presence of significant amount of linolenic acid in soybean oil, which is prone to oxidation. The rate of oxidation of all blends is slow as compared with pure soybean oil. When corn oil was blended with Soybean oil iodine value of soybean oil decreases and progressive changes observed in the peroxide value that is oxidative stability of Soybean oil increases. Corn oil has better shelf life than the soybean oil, Hence when soybean oil is blended with corn oil there is an increase in shelf life stability of soybean oil. Thus the present study of three blends certainly help to improve shelf life of soybean oil as compared to pure soybean oil. Fatty acid composition in Shelf Stability (at room temperature) linolenic acid content for pure soybean oil is (6.6), and Soybean oil ,Corn oil composition linolenic acid content (5.6), (5.3), (4.9), (3.5), (2.9) and for pure corn oil (0.7) (Table 5)..After 42 hours value of free Fatty acids are changed. It is indicated that, when soybean oil blended with corn oil there is decrease in value of linolenic acid content. After 42 hours also linolenic acid content show decrease comparing to initial stage of blending. The blend of Soybean oil with the corn oil shows good stability. Figure 1 : Graphical Represents of Iodine value of blends. Figure 2 : Graphical Represents of peroxide value of blends. Figure 3 : Graphical Represents of FFA value of blends. REFERENCES Saska, M., and Rossiter, G. J., J. Am. Oil Chem. Soc., 68:436-439 (1991). Handoo, S. K., Gupta, Sanjoy., and Agarwal, T. N., J Oil Tech. Assoc. of India. 24:83 (1992). Handoo, S. K., Bagga, K. K. and Sharma, K. P. J. Am. Oil Chem. Soc., 26: 91 (1994). Young,C., in Balley’s industrial Oil and Fat products,5th edition, Interscience publication,2, .339. (1996). Bhattacharya, D. K.., J. Am. Oil Chem. Soc., 77:1683-1686 (1998). McCaskill, D. R., and Zhang, F. J. Am. Oil Chem. Soc., 53:50-54 (1999). Chopra, Rainy., and Nagraj, G., J. Am. Oil Chem. Soc., 36:21 (2004). Oil Technology Association of India., (Source: SEA News Circular), 8,(2006). Choe, Eunok.,, David., B., Comprehensive review in Food Science and Food Safety.2, (2006) Choe, E., D., Min. B., Journal of Food Science.. 72, R77–R86, (2007). Basturk, Ayhan.., Javidipour, Issa., and Boyaci, Ismail, H., Journal of Food Lipids 14, 170–188, (2007). 12. Ryan, Liliana, C., et al., International Journal of Food Science Technology, 43, 193–199, (2008). Francisca, Manzanarez-LÃ ³pez., et.al., Journal of Food Engineering. 104, 508–517, (2011). Fawzy, Mohamed., Mohamed Khaled, Wahdan. M., Food Chemistry, Volume 132, 873-879, (2012). Teresa, Maria., Simon, A., Haughey, Christopher., Elliott, T., Anastasios Koidis, Food Research International.10,1016, (2013).

Gullah

The recent rise in Black consciousness has created an extraordinary interest in the study of Black heritage and the preservation of Black culture in America. Many scholars and students are turning their attention to A frican-American cultural patterns, which have been long ignored and often scorned. Black people are realizing more and more that these patterns exemplify key features of their heritage and may offer not only clues into the past, but also provide guides to survival in the future.As this interest gains momentum, African-Americans are looking toward the South, particularly to its rural and isolated islands where so many of the unique elements of contemporary Black culture have their roots. The culture of the Sea Islands is such a special case. The lack of contact with the mainland helped to preserve some of the important features of their African culture. Because the Africans that were brought to these islands were not sold and resold as often as those on the mainland, som e of their ancestral family patterns remain even to this date. ——————————————————————————- A. Sea Islands Begin just north of Georgetown, South Carolina, and continue to the Florida border. It is estimated that there are approximately 1,000 islands along the coast of South Carolina and Georgia separated from the mainland by marshes, alluvial streams and rivers. 1. Some of the islands are bordered by the Atlantic Ocean and are as far as twenty miles or more from the mainland. 2. They range in size from the uninhabitable ones to John’s Island South Carolina, the second largest island in the United States.B. European settlement 1. The Sea Islands have formed the basis of a very profitable agriculture. 2. During slavery, the long staple cotton grown here was considered the best available anywhere and brought very favorable prices on the world market 3. The economy of the region was based almost entirely on slavery, and because of the labor intensity of the crops, very large plantations developed in this area. a. Some Whites owned entire islands containing thousands of acres of land and maintained hundreds of slaves to till the soil. C. Isolation 1.The isolation of the islands and the large numbers of slaves meant that the influence of American White culture upon African and slave culture was minimal. 2. To further enhance the development of a unique Black culture, there was the continual importation of slaves directly from Africa. a. The overwhelming number of slaves entering South Carolina during the 18th century came directly from Africa. b. The isolation of the islands made them a prime location for slave traders to land illegal cargoes of Africans after the Slave Trade Act of 1808. c. Africans were imported into the islands as late as 1858.D. Cultural formations 1. There was a geographical, social and cultural basis for the retention of many elements of African culture in the Sea Islands and the development of a distinctive African-American culture. 2. The word â€Å"Gullah† was once defined as the way of speaking of Blacks on the Sea Islands. In recent years, Gullah has come to mean not only the speech of Black islanders but also their culture and way of life. a. Food- traditional seafood and rice dishes â€Å"Hoppin John† and â€Å"Frogmore Stew† b. Arts-basket weaving, donning fishnets, pottery, and quilting. . The first American cowboys were the Blacks in the Carolina low country (Sea Islands). d. Contributions to American music are also evident. e. Tradition of fishing passed from one generation to another. f. During the slave period many of the customs the people developed clearly reflected African culture and post-bellum conditions enhanced their retention. Basket weaving is one of the dominant crafts of the region, and one of the oldest crafts of African origin in theUnited States. Crabbing and fishing are a very important part of the Sea Island culture.Sea Island children are intimately familiar with the ocean and learn the art of casting and netting as early as the age of three. E. Development of survival patterns 1. Philosophy and utilization of time. Older Blacks have a different relationship to time than many younger and â€Å"up to date† Blacks. 2. Environment coping a. Dealing with atmospheric changes F. Psychological and sociological issues. 1. Many Sea Island Blacks may have different self perceptions and attitudes as compared to Blacks raised in other areas. 2. The Sea Island Blacks frequently owned their land since the years before Reconstruction.Many of them do not know what it means to pay rent or a mortgage and to some the very concepts are meaningless. 3. The fact that the people were very isolated from mainstream culture, they could only survive by developing a posture of self-s ufficiency and independence. 4. Many elderly Sea Island Blacks had very limited interaction with Whites. 5. Black activism of Sea Island Blacks a. Some of the earliest support for the civil rights movement came out of the Sea Island and Martin Luther King developed some of his major campaigns during retreats to the area. . Local independence and activism has its roots in the Reconstructionist Era and the Black majority in the area. c. A large portion of the elderly Sea Islanders registered to vote before 1910. G. Uniqueness of Sea Islands 1. They are home of a West African people called Gullah. They were captured from this area because the Europeans needed technology and labor to build their empires and America. The Gullah captives possessed skills (technology) in agriculture, science, animal farming, construction, navigation, government, and teaching. 2.The knowledge and need for farming and building in the Sea Islands required specialized skills that were found in abundance in Wes t Africa 3. The isolation of the Gullah from mainland whites and other Africans allowed the Gullah to maintain a high degree of African culture. Also, the high concentration of Africans allowed a Gullah community to form an Afrocentric cultural entity within a European American cultural context. H. Gullah Dialect 1. The Gullah â€Å"accent† is much more than just an accent on the English language. Gullah, as a language, uses distinct African language patterns, and conceptual meanings.In other words, the Gullah language is uniquely African, with English words added to it. 2. One study says that the origin of the term Gullah and the Blacks came from the West Coast of Africa, but exactly where has not been agreed upon. a. One is that Gullah is a shortened form of Angola, the name of an African West Coast district lying south of the Equator and the mouth of the Congo River. b. A second suggestion is that Gullah comes from the name of the Liberian group of tribes known as Golas li ving on the West Coast between Sierra Leone and the Ivory Coast. . Gullah has been called the most African of any of our Black dialects, yet it can be traced back in practically every detail to English dialect speech. There has been an interchange of cultural values between the Black and White communities who have lived and worked together on the Sea Islands from the first days of settlement. The dialect was nourished in isolation and has survived with little change because of the continued isolation of its native area. The Parable of the Lost Sheep, Luke 15:2-3 King James VersionAnd the Pharisees and scribes murmured saying, this man receiveth sinners and eateth with the them. And he spake this parable unto them, saying What man of you, having an hundred sheep, if he lose one of them, doth not leave the ninety and nine in the wilderness and go after that which is lost, until hefind it? Gullah Version En de Pharisee en de law teesha dem saat ta mek cumplain,say â€Å"Dis man sociat e widsinna en ebn eat mong am. Now den Jesus done know dem binna nek cumplain bout am. So e tell am one parryubble, say â€Å"Supposin a hondad sheep blonks ta one a oona.Ef one a dem sheep done loss een de wood wa you fa do? Sho nuf, you gwain lef de ninety-nine oddares safe een de pasta. You gwain saach fa de one wa loss tel you fin am eni? † I. Sea Islands Today 1. Today, an estimated 270,00 people along the Georgia, Carolina, and northeastern Florida coasts speak of Gullah. The dialect survived primarily among rural Blacks who largely depended on farming and fishing. Many of these people are now moving into jobs in the various resort industries, which are springing up on the islands, thus ending their isolation.Nonetheless, Gullah has a way of surviving even in small clusters in New York City where its speakers are often mistaken for Barbadians. 2. Because many corporations are now building their resorts on the islands and the United States Marine Corps has established a training base on Paris Island, many sociologists theorize the Gullah culture will soon die out. Nonetheless, although the pressures on the Gullah culture to disintegrate and assimilate are great, there are a number of people who are making valiant attempts to maintain, and preserve this treasured culture.

Conflict in literature Essay

All conflict in literature is, in its simplest form, a struggle between good and evil†. This statement simplifies the idea that all themes and struggles in literature when broken down to their most basic forms are a conflict of good versus evil. This is a valid statement because good and evil are the basis of all conflict. A conflict is a two-sided and any struggle implies a difference of opinion or emotion which can be broken down into both â€Å"good† and â€Å"evil† parts. such works that emphasize this statement are George Orwell’s novel, â€Å"Animal Farm† and the play, â€Å"Othello†, a tragedy written by William Shakespeare. William Shakespeare’s use of characterization in â€Å"Othello† describes the character Othello as a brave, courageous, and honorable soldier. Shakespeare also introduces the complete contrast of Othello in the character Iago. Iago is portrayed as two-faced and manipulation, representing the evil aspect in the play. Shakespeare uses Iago to take advantage of Othello’s trusting personality and to attack Othello’s good nature. Othello becomes overridden with hate and jealousy, which consume all of his other emotions. Othello is an example of how a character can cross the line between good and evil. The relationship between Othello’s character and Iago’s character can be viewed as a battle of the two forces. â€Å"Animal farm† is a modern political novel set in the Twentieth Century. Disliking their owner, the animals of Animal Farm attempt to revolt with the intention of setting up a â€Å"perfect† Utopian society for themselves, a society without the evil of humans. With the help of two intelligent pigs, Snowball and Napoleon, the animals were able to defeat their enemy and conquer animal far. Towards the end of the novel, we discover that Snowball and Napoleon are highly influenced by the actions of humans. Years pass on Animal farm and we find that the pigs become more and more like human beings by walking upright, carrying whips, and wearing clothes. In the end, the pigs backfire on their original plan of eliminating humans but instead, joined them. In conclusion, the struggle of good and evil is a basic struggle that is common in all novels. This common struggle is illustrated in Shakespeare’s  Ã¢â‚¬Å"Othello† and George Orwell’s â€Å"Animal Farm† through various themes and characterizations.

Analysis Of Alasdair Gray s Songs Of Innocence And Of...

Intermediality comprises the combination of the literary text with other media or forms of art, or the incorporation of such media and forms into the literary text. The combinatory mode, which is known from illustrated novels of the nineteenth century, gained new prominence in Alasdair Gray’s self-illustrated novel Lanark (1981) and in comic books or ‘graphic novels’ by writers such as Alan Moore and Neil Gaiman. With regards to English Romantic poet William Blake, both his lyrical Songs of Innocence and of Experience (1789-94) and his prophetic poems of epic length were conceived as an intermedial work made up of text and illustration. Blake’s collection of poems; Songs of Innocence and of Experience Showing the Two Contrary States of the Human Soul (1789-94) seemingly concerns contradictory ideas. It is intended as a look at two contrasting perceptions of the world, as envisaged by ‘the Two Contrary States of the Human Soul, with each group of poems serving as one half of the two contrary states. The pairing of opposites is the principle underlying this collection of contrary poems, some of which are headed by identical titles. The â€Å"Introduction† to the Songs of Innocence highlights the process from piping or singing a song to the writing down of the text, that is, the journey from orality to scripture. Its counterpart in the Songs of Experience is tinged by prophetic overtones (â€Å"Hear the voice of the Bard!†). In ostensibly simple terms, the two contrary poems â€Å"The