VOLUME 34, NO3, JUN 2012
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Physicochemical Characterization and Frying Quality of Canola and Sunflower Oil Samples

SHAZIA TABASUM ,HAFIZ BADARUDDIN AHMAD ,SANIA ASGHAR ,NAEEM AKHTAR ,SADAF NAZ ASHRAF ,

Normal 0 false false false MicrosoftInternetExplorer4 Frying quality of canola and sunflower oils was evaluated. Stimulated frying experiments were performed on oils with French fries as the fried food. Samples of oils were used to fry potato chips for four days. Physical and chemical characterization was carried out to determine the change during frying. Comparison of frying oil samples was then made with their control counterparts (i.e. oil samples without frying). There was a gradual increase in refractive index, viscosity, acid value and colour with time of frying. Iodine value decreased significantly with time of frying. Peroxide value first increased up to 12 h of frying and then decreased. Colour change and viscosity increase with increase in frying time. Amount of free fatty acid gradually increase during frying. Refined oil showed better performance than the crude oil due to the presence of impurities in the latter.
Pages(513)
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Quality Evaluation and Safety Assessment of Different Cooking Oils Available in Pakistan

TAHIR MEHMOOD ,NAUMAN KHALID ,ASIF AHMAD ,ANWAAR AHMED ,

Normal 0 false false false MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} The present study was conducted to evaluate the quality of cooking oils available in Pakistani market. The physicochemical qualities of 35 commercially available cooking oil brands were investigated for free fatty acid, peroxide value, smell, weight, color, rancidity, foreign matter, appearance and cold point. Analysis showed that free fatty acid, peroxide, smell, weight and rancidity value significantly deviate from standards set by Pakistan standard quality control authority (PSQCA). However, color, foreign matter, appearance and cloud point values were in limits set by PSQCA. In terms of vitamin only 71.43±2.32% brands contain vitamins. These results confirm the presence of adulteration and deviation of product development from quality limits sets by Pakistan standard quality control authority.
Pages(518)
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Effect of Heat Treatment on the Structural Characteristics and Dehydroxylation Kinetics of the Tunellite

SABRIYE PISKIN ,MUGE SARI YILMAZ ,

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} The effect of heat treatment on the structural properties of the tunellite has been investigated in the present study. The tunellite samples were calcined in a furnace for 5 h at three different temperatures, 400, 710, and 800°C. These temperatures were determined with respect to the DTA/TG curve. The calcined tunellite samples were characterized by X-Ray Diffraction (XRD). It was found that with increasing calcination temperatures, a veatchite phase was observed. The morphology of the calcined tunellite samples was characterized by Scanning Electron Microscope (SEM). According to the results of the analyses, it was observed that the calcination temperature influenced the shape of the tunellite. The Brauner-Emmett-Teller (BET) analysis revealed that the specific surface area of the samples decreased with an increasing calcination temperature due to the shrinkage of the agglomerates. In addition, the dehydroxylation kinetics of the tunellite was studied by the thermogravimetric technique. The non-isothermal kinetic data were analyzed and the kinetic parameters for the dehydroxylation stage were computed by 21 solid-state mechanisms. In addition, the kinetic compensation effect (KCE) was also used in order to correlate the pre-exponential factor with the activation energy.
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Use of TiO2 as Catalyst in Degradation Induced with Gamma Radiation of Methylene Blue

GABRIELA G. CANO-GARCIA ,JAIME JIMENEZ-BECERRIL ,ALMA MARTINEZ-HERNANDEZ ,

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Heterogeneous radiocatalysis is a catalytic process promoted by the direct adsorption of high radiant energy capable of activating a semiconductor such as TiO2, which generates free radicals very reactive at the surface that allow oxidation-reduction reactions with adsorbed species, breaking some molecular bonds and reducing or oxidizing them less complex species. We irradiated methylene blue with 60Co gamma rays and added of TiO2 during irradiation with different doses of gamma radiation, measuring the remaining methylene blue concentration by spectrophotometry UV. The degradation of the organic compound was enhanced when doses increased and with the addition of semiconductors of up to 1g of catalyst per liter of suspension.
Pages(533)
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Spectrophotometric Determination of Diazepam

NAEEM ASGHAR KHAN ,NARJIS NAZ ,NADEEM ASGHAR KHAN ,NAVEED ASLAM DOGER ,WASEEM ASGHAR KHAN ,

Normal 0 false false false /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Diazepam reacts with ninhydrin at pH range 12-12.5 to give a violet color having maximum absorbance at 530 nm wavelength. The reaction is specific for diazepam and provides a basis for its spectrophotometric determination. The color reaction obeys Beer’s law from 0.1 to 2 mg/10 mL of diazepam. Coefficient of variation and confidence limit determination are 0.06 and 0.0041%, respectively. The relative standard deviation is 1.5%. The quantitative assessments of tolerable amount of other drugs have also been studied.
Pages(536)
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Accumulation of Pesticide Residues by Shrimp, Fish and Brine Shrimp During Pond Culture at Ghorabari (District Thatta)

M. NASIR ,ALIA BANO MUNSHI ,F. AMEER ,RAZIA SULTANA ,WAJEEHA ALI ,

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Residual  level of persistent organochlorines (OC) such as ∑HCH (α–HCH, β–HCH, γ–HCH, δ–HCH, ∑DDT (o,p'-DDD, op-DDE, p,p-DDE pp–DDD, pp'-DDT, o,p'-DDT), dieldrin and endrin were measured in a number of water samples from Ambro creek and their accumulation in shrimp (Penaeus merguiensis and P. penicillatus), fish (Otolithes ruber) and brine shrimp (Artemia sp.) reared in ponds for a period of four months. Samples were extracted with organic solvents, and quantified using gas chromatography-electron capture detection (GC/ECD). It has been found that results of animal tissue and water are not same however OCs, (mainly ∑DDT and ∑HCH 4,4-DDT, Dieldrin+2,4-DDT, and Methoxychlor were detected in all samples ). Heptachlor exo-epoxide were found in fish and Artemia sp. and absent in all shrimp samples. Heptachlor endo-epoxide was detected only in Artemia sp. and average residual concentration of OCs in Artemia sp. was 0.004-0.09 ppm. Methoxychlor was found in the highest quantity in all the samples whether it was fish, shrimp or Artemia. In fish average residual concentration of all (OCs) in individual sample was 0.03 – 0.180 ppm.
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Physico-Mechanical Studies of Natural Rubber/Carbon Black Vulcanizates Containing Reclaim Rubber

NUDRAT ZAHID RAZA ,KHAULA SHIRIN ,KHALID MAHMOOD ,KHALIL AHMED ,

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Locally available reclaim rubber (RR) was used in this study. It was characterized in terms of its oil soluble parts by acetone extract, rubber identified by pyrolysis and FT-IR, carbon black from TGA and ash content by ignition. The RR was utilized in place of natural rubber (NR) in natural rubber/ carbon black compounding. The physico-mechanical, cure characteristics and swelling properties of the vulcanizates were investigated as a function of RR/NR loading. The minimum and maximum torque, cure time, compression set, hardness, swelling index, swelling coefficient, mol percentage uptake of solvent increases with increasing the amount of reclaim rubber but tensile, strength, elongation at brake, rear strength, resilience, scorch time & volume fraction of rubber vulcanizate decreases. Accelerated aging performance also effected with increasing the loading of reclaim rubber in vulcanizates.
Pages(550)
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Ultrasonically Assisted Extraction and HPLC Determination of Chondroitin Sulfate from Fish Heads

CHUN LIN KE ,XIAO XIONG ZENG ,

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} In the present study, we investigated the ultrasonically assisted extraction(UAE) and high-performance liquid chromatography (HPLC) determination of chondroitin sulfate(CS) from fish heads. Firstly, the optimized parameters for CS extraction were obtained by using Box–Behnken design(BBD) and response surface methodology(RSM) based on the single-factor experiments. As results, the optimum conditions were ultrasonic time 45min, ultrasonic power 280W and solvent/material ratio 6ml/g. Under these conditions, the experimental yield of CS was 4.623%. Secondly, the CS was purified by DEAE-Cellulose 52 chromatography and Sephadex G-100 chromatography to afford purified CS. Finally, we developed a simple method for the determination of glucuronic acid (GlcA) and N-acetylgalactosamine (GalNAc) in purified CS by HPLC with a diode array detector (DAD). The results showed that there were obvious saccharides peaks in CS.
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GC-MS analysis of Fatty acids (FAs) of Prosobranch

NUZHAT AFSAR, GHAZALA SIDDIQUI, MUNAWWER RASHEED, VIQAR UDDIN AHMED AND AFSAR KHAN

Normal 0 false false false MicrosoftInternetExplorer4 The fatty acids (FAs) composition was analyzed in digestive gland/gonad complex of male and female specimens of Thais carinifera by gas chromatography-mass spectrometry (GC-MS) technique in identification of fatty acids (FAs). Saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and steroidal components formed a large proportion of total lipids. Palmitic acid (16:0) and stearic acid (18:0), 11 eicosanoic acid, 5-13-docosadienoic acid and Cholesterol was  found in abundance as SFA, MUFA, PUFA and steroidal constituent respectively in both male and female samples. Multi-methyl branched, methyl branched and hydroxy FAs contributed a smaller proportion. Presence of fair amount (~20%) of PUFA along with cholesterol (~24%) in Thais carinifera is unique because of their role in human health. This is the first ever report revealing the FAs and steroidal composition of this species.
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Preparation of Industrial Chemicals by Acid Leachi

ABDUR RAUF NIZAMI

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} This paper encompasses the study on the preparation of industrial chemicals by acid leaching from the Koga nepheline syenite, Southern Swat, Lesser Himalayas-Pakistan. These rocks have been studied in detail by many workers to exploit their industrial utility in the form of powdered rock material in glass and ceramics and steel industry. The present authors for the first time carried out acid leaching studies and prepared a number of industrial chemicals, like, alumina, aluminium sulphate, sodium and ammonium alums, sodium sulphate) and sodium bisulphate by simple chemical reactions at bench scale successfully. The developed process is simple and economically viable. It is recommended to exploit this process in cottage industry in the mountainous areas hosting these rocks for the benefit of local population. The research and development work for production of these chemicals at pilot plant and industrial scale is recommended as well.
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