1.
Effect Of Different Heat Treatments On Antioxidant Activity Of Eggplant And Its Efficacy Study Dr. Sanaullah Iqbal
by Wajeeha Baig | Dr. Muhammad Nasir | Prof. Dr. Habib-ur-Rehman.
Material type: ; Literary form:
not fiction
Publisher: 2014Dissertation note: Eggplants (Solanum melongena L), are native to the South East Asian region and were first domesticated there over 4000 years ago. In fact, the eggplant’s true species name ‘‘Melongena’’ is an ancient name for eggplant in Sanskrit (Spurling, 2003). The color, size, and shape of the eggplant fruit vary significantly with the variety of cultivar. Eggplant is one of the most common vegetables that is grown and consumed all around the world (Nisha et al. 2009). Thomas Jefferson introduced eggplant to the United States in 1806. Even today, a prickly, white eggplant still grows in Jefferson’s preserved Vir-ginia Garden at Monticello (Filippone et al. 2009). Eggplant fruit contains ascorbic acid and phenolics e.g chlorogenic acid, flavonoids, acetylated chlorogenic acid isomers, hydroxycinnamic acid oxides conjugates caffeic acid ,both of which are powerful antioxidants (Vinson et al. 1998). Eggplant is commonly considered as a vegetable, but botanically it is categorized as a fruit. Eggplant fruit is ranked among the top ten vegetables in terms of oxygen radical absorbance capacity due to its high phenolic content (Cao et al. 1996). A comparative study of the antioxidant capacity of different varieties was recently reported by two separate groups of researchers (Huang et al. 2004; Nisha et al. 2009). Vegetables contain several hydrophilic and lipophilic antioxidant compounds and it is important to estimate the antioxidant activity using different methods. They may act together more effectively than singly because they function synergistically and are capable of quenching free radicals in both aqueous and lipid phases (Ohr et al. 2004; Trombino et al. 2004). Antioxidant components are micronutrients present in the diet that can delay or inhibit lipid oxidation, by inhibiting the initiation or propagation of oxidizing chain reactions, and are also involved in scavenging free radicals (Othman et al., 2007). Epidemiological studies have shown that high fruit and vegetable consumption has health benefits in the prevention of chronic diseases (Cheel et al., 2007). The influence of home cooking methods (boiling , pressure-cooking , frying ) on the antioxidant activity of vegetables has been evaluated in 20 vegetables, using different antioxidant activity assays (lipoperoxyl and hydroxyl radicals scavenging and TEAC). Artichoke was the only vegetable that kept its very high scavenging-lipoperoxyl radical capacity in all the cooking methods. The highest scavenging capacity were observed in cauliflower after boiling and microwaving , in pea after boiling , and in zucchini after boiling and frying. Beetroot, green bean, and garlic kept their antioxidant activity after most cooking treatments. Swiss chard and pepper lost OH (Enez –Monreal et al. 2009). In the case of boiling or pressure-cooking occurs lixiviation phenomenon that leads to a 64% loss of total carotenoids and a 49% loss of total phenolics (Bunea et al. 2008). The phenols enter the cooking water and complex phenol proteins are found, reducing drastically by 90% or more (Barroga et al. 1985: Rocha et al. 2007). Eggplant is one of most common vegetables consumed all around the world. The present study will evaluate the antioxidant potential of two different varieties of eggplant (long purple coloured big size, and rounded purple coloured small size) in terms of total phenolic content (TPC), 2,2,di-phenyl-2-picrylhydrazyl (DPPH), superoxide radical scavenging activity, and total anthocyanin content. Extracts from purple colour small size eggplant demonstrated better antioxidant activities than the other samples which may be attributed to the higher phenolic and anthocyanin content since a linear relation was observed between the TPC and the antioxidant parameters (Nisha et al. 2009). There is comparison of among vegetables regarding to their antioxident capacity.
Tab.1.1: Comparison of different vegetables with respect to their antioxidant capacity
Vegetables Size Total antioxidant capacity
Russet potato 1 whole 4,649
Artichoke Half cup 4,402
Small red bean Half cup 13,727
Eggplant 1 whole 4,035
Red kidney beans Half cup 6,000
In the present study , the focus is on the amount of the antioxidants in eggplant after the application of different heat treatments. As eggplant is good source of antioxidants, it has been observed from different studies that heat leaves adverse effect on nutritional status of fruits and vegetables. Pakistan is one of the countries who has good cultivation rate of eggplant.
One hundered gram of fruit contains 0.7mg iron, 13.0mg sodium, 213.0mg potassium, 12.0mg calcium, 26.0mg phosphorus, 5.0mg ascorbic acid and provides 25.0 calories (Yousafi et al.2013).
In world production ranking, Pakistan is at 20th position in the eggplant production. Pakistan produces 87,000 tons eggplant every year. Moreover, it has 0.2% sharing in world wide eggplant production. It is cultivated in 9,044 ha on the land of Pakistan (FAO, 2012).
Hydrogen Peroxide is one of the most powerful oxidizers known -- stronger than chlorine, chlorine dioxide, and potassium permanganate. And through catalysis, (H2O2) can be converted into hydroxyl radicals (.OH) with reactivity second only to fluorine.
Hydrogen Peroxide (H2O2) is a colourless liquid that resembles water in many respects. Its physical properties are very similar to those of water, except that it is 40% denser. The main difference between hydrogen peroxide and water, however, is in its chemical behaviour. The single bond between the two oxygen atoms is weak, so that H2O2 readily fragments into either H and HO2 or two OHs. Either way, the resulting species are free radicals, which means they are very reactive, and this makes H2O2 a very powerful oxidizing agent. For this reason it has been utilized in rocket propulsion, when it is used to oxidise the hydrazine fuel, liberating hot gases (steam and oxygen) which propel the rocket forward. When something acts as an oxidising agent is gains electrons (removing them from the oxidised species) (Ganie et al., 2009).
For this purpose, this study has been designed to find out the appropriate method to cook eggplant at domestic level, so that maximum level of antioxidants could be obtained in our food, because antioxidants play a very important role in prevention of many chronic diseases. So, four different cooking methods i.e, grilling, cooking under pressure, boiling and deep frying has been selected for this study because these cooking methods are applied frequently at domestic level.
Availability: Items available for loan: UVAS Library [Call number: 2191,T] (1).
2.
Effect Of Oiling And Packaging On Shelf Life Of Eggs Stored At Two Different Temperatures
by Marium Munir (2008-VA-388) | Dr. Muhammad Nasir | Dr. Sanaullah Iqbal | Dr. Aftab Ahmad Anjum.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: In Pakistan, poultry industry is playing a vital role in the economy of the country. As eggs are perishable so it must be handled with safety. It is imperative to handle and store the eggs at appropriate conditions. But improper storage of eggs is a problem in our country which affects its quality and there is chance of microbial contamination in eggs. Oiling and packaging has variable impact on shelf life of eggs at different storage temperatures (Matt et al. 2009).Raw eggs have many benefits, they contain essential nutrients for the brain, nerves, glands and hormones, they are nutritionally balanced. raw eggs also contain an abundance of other vital substances including protein, essential fatty acids along with niacin, riboflavin, biotin, choline, vitamins A, D and E, magnesium, potassium, phosphorous, manganese, iron, iodine, copper, zinc and Sulphur. Egg yolks are one of the few foods that contain vitamin D(Watkins, 2002). As eggs are perishable food stuff,so the purposes of present research work are to analyze the effect of oiling and packaging on shelf life of eggs at two different temperatures. For this a total of 864 eggs were collected. The four different treatments were applied along with two different temperatures. Each category was further divided into four treatment strategies (108 eggs in each strategy) i.e. eggs without any treatment, oil coated eggs, eggs packed (air-tight) in white polythene bags, oil coated eggs packed (air-tight) in white polythene bags.Eggs undergone each treatment strategy were analyzed for six parameter i.e. sensory evaluation, microbial load, Physical parameters (weight, pH, egg shell percentage and haugh unit) using 18 eggs for each further divided into three replicates (6 eggs for each replicate). All the eggs were stored for 1, 7, 14, 21, 28 and 35 days.
Summary
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Data was analyzed statistically by the 2- way ANOVA (Analysis of Variance) with 5% probability. Means was compared by DMR test.At the end of this study we were able to assess the shelf life of eggs with respect to their oiling, packaging and storage conditions. Availability: Items available for loan: UVAS Library [Call number: 2289-T] (1).
3.
Effect On Lipid Profile Parameters By The Addition Of Orange Juice In Diet Of Hypercholesterolemic Patients
by Zeshan Ali (2012-VA-616) | Dr. Naureen Naeem | Dr. Sanaullah Iqbal | Mrs. Rahat Naseer.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: Orange juice;arich source ofvitamin C,folate,andflavonoidssuchashesperidine, induceshypocholestremicresponsesinanimals.Previousepidemiologicstudiessuggestedthat ahighintakeoffruitandvegetablesisassociatedwithareducedriskofcoronary heartdisease(Borsetal.1990).Thebeneficialeffectcould berelatedtominorcomponents,especially flavonoids,whichare proposedtoexerttheiractionby inhibitingLDLoxidation (CooksandSamman1996).Orange juice might beneficially decrease blood lipid profile in subjects with hypercholesterolemia(Charleux1996).
Fiftysubjectshavingelevated totalcholesterol andLDLcholesterolincludedin thestudy.Participantswas incorporate2cups(5000mL)oforange juicedailyintotheirdiets,eachdoseoveraperiodof3 weekfollowed by a 5-weekwashoutperiod.Plasma lipid,folateandvitaminC(acompliance marker) concentrationsmeasuredat baseline,aftereach treatment, and afterthewashout period.Obtained resultswereanalyzedbyusingstatisticaltoolANOVA (two-way)onStatistical PackagefortheSocialSciences (SPSS) softwareversion 21.0.0.Attheendofthis studywewereabletoconcludethe variationin lipidprofile parametersbyorangejuiceconsumption.EitherOrangejuicecanbeusedtoimproveblood lipidprofilein hypercholesterolemicsubjects.
At the end of the study period the significantly increased HDL- cholesterol and decreased LDL-HDL cholesterol ratio had not reverted to initial values. In fact, the decrease in the LD-HDL cholesterol ratio and increased HDL- cholesterol at the time of washout tend to be higher as compared to the detected in 3rd period. Moreover it was also observed that subjects consuming processed orange juice showed different results of HDL and LDL-HDL cholesterol concentration, subjects consuming fresh orange juice had elevated level of HDL and decreased ratio of LDL-HDL ratio as compared to those who intake commercially available processed orange juice.
Availability: Items available for loan: UVAS Library [Call number: 2309-T] (1).
