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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Mechanical oil expression from selected oilseeds under uniaxial compression

Bargale, Praveen Chandra 01 January 1997 (has links)
Mechanical pressing of soybean is highly desirable as it provides, at low cost, non-contaminated, protein-rich, low-fat soyflour which can be further processed into nutritious edible foods. Unfortunately, mechanical pressing of this low-fat oilseed ($<$20%) yields only 50-70% of the available oil, in contrast to the solvent extraction method which recovers over 98% of the oil. The main focus of the study was to maximize the oil recovery from soybean using mechanical oil expression by applying two pretreatments, enzymatic hydrolysis and extrusion cooking of soybeans, and by varying the pressing conditions including three applied pressures (20, 40 and 60 MPa), three pressing temperatures (22, 60 and 90°C) and two sample sizes (10 and 20 g). To characterize the material properties affecting mechanical oil expression from soybean a mathematical simulation of uniaxial compression was developed which incorporated the time dependent variation of soybean properties. The mathematical simulation was based on Terznaghi's theory of consolidation for soils and was solved using measured values of the coefficients of permeability, volume change and consolidation. A compression-permeability test cell was specifically developed for these measurements. For validation of the model, in addition to extruded soy, sunflower seeds (oil content ca. 45%) were also compressed under the same pressing conditions. Improvements in oil recovery due to enzymatic pretreatment of soybean were small, while the extrusion pretreatment increased the oil recovery from only a trace for raw soybean to 90.6%. Such oil recovery using mechanical pressing of soybean has not been reported in the past. The measured values of oil recovery, coefficients of permeability, volume change and consolidation for soybean and sunflower seeds were found to vary significantly $(P<0.05)$ with time of pressing, applied pressure, pressing temperature and the size of the sample. For extruded soy samples, the developed model predicted the values of oil recovery versus pressing time with an average error of 15%, while for sunflower seed samples the average prediction error was 40%. The high error values were attributed to the presence of hulls in the sunflower seed samples, as well as error during measurement of the coefficient of permeability. The coefficient of consolidation was found to have the greatest influence on oil recovery. The incorporation of time dependent material properties in the developed simulation was demonstrated to give more accurate and consistent prediction in trends of oil recovery as compared to using constant material properties. The correlationship developed between the oilseed material properties and the oil recovery obtained from uniaxially compressed oilseeds would help researchers and designers to better evaluate the mechanical oil expression equipment and systems. To the extent that the developed model adequately predicted oil recoveries from both sunflower and soybean oilseeds, the model is expected to be applicable to other oilseeds as well.
372

The effect of liquor composition on the rate of reaction of a lignin model compound (acetovanillone) under oxygen-alkali conditions

Mih, Jer-Fei 01 January 1982 (has links)
No description available.
373

Effect of digestion on wood structure

Bixler, A. L. M. (Andrew Loy Moore) 01 January 1937 (has links)
No description available.
374

Highly efficient procedure for the synthesis of biodiesel using ionic liquid as catalyst

Lin, Jia-fang 16 July 2012 (has links)
This study used jatropha oil, waste cooing oil, and soybean oil as the raw materials for investigating effects of catalyst concentration, reaction time, reaction temperature, methanol-to-oil ratio, and catalyst types on biodiesel yield. The authors also heated up the oil to speed up the transesterification and to make the reaction more complete. Jatropha oil, waste cooing oil, and soybean oil were used as the raw materials, and three types of ionic liquid or zwitterionic liquid, [PyrMe][HSO4], [PyrMeBuS][HSO4], and [MorMeA][Br], were added as catalysts for co-catalysis while heating the oil raw materials to create the best operational condition for biodiesel production. For soybean oil used as the raw material, the best catalyzing effect (a 99.4% yield) was achieved by adding [MorMeA][Br] while the reaction time was 6min, reaction temperature was 70 ¢J, and the methanol-to-oil ratio was 9:1. Under the best reaction condition, catalyzing effect was compared between the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid. The yield of the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid were 97.2% and 98.7% respectively. It can be found from this study that for increasing biodiesel yield, the addition of zwitterionic liquid for co-catalysis is more effective than the addition of homogeneous ionic liquid. Comparing the best operational condition between jatropha oil and soybean oil, the best yield of jatropha oil and soybean oil was 98.5% and 99.4% respectively, while the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 6 min, and the reaction temperature was 70¢J. As for disposed cooking oil, the best operational condition rendered a yield of 98.1% when the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 7 min, and the reaction temperature was 70¢J. For waste cooking oil, because of the containing of impurities from frying, the yield was slightly lower and the reaction time was longer.
375

Treatment of Volatile Organic Compounds in Cooking Oil Fume Emitted from Restaurants by Nano-sized TiO2 Photocatalyst Coated Fiberglass Filter and Ozone Oxidation Technology

Lai, Tzu-Fan 20 August 2012 (has links)
Recently, restaurant employees exposing to cooking oil fume with potential lung cancer was highly concerned, indicating cooking oil fume emitted from restaurants might cause tremendous hazard to human health. This study combined photocatalytic oxidation and ozone oxidation technology to decompose VOCs from the exhaust of cooking oil fume from restaurants. Firstly, this study selected three different types of restaurants to implement air pollutant measurements in the indoor dinning room and stack emission. Indoor TVOCs continuous monitoring data showed that the highest TVOCs concentration was generally observed in the dining peak time. In this study, photocatalyst coated fiberglass filter was prepared by impregnation procedure and its characteristics was analyzed by SEM and XRD. Experimental results showed that the particle size of photocatalyst ranged from 25 to 50 nm and had high percentage of Anatase, suggesting that it had high photocatalytic reactivity. This study designed a continuous-flow reaction system combined nano-sized TiO2 photocatalysis with ozone oxidation technology to decompose VOCs from cooking oil fume. After passing through a fiberglass filter to remove oil droplets, the cooking oil fume then coated with nano-sized titanium oxide (UV/TiO2) fiberglass filter purification system, and then injected ozone into the system to decompose residual VOCs. This study further investigated the influences of operating parameters, including TVOCs initial concentration, O3 injection concentration, and reaction temperature on the decomposition efficiency of TVOCs by using the UV/TiO2/O3 technology. When the photocatalytic reaction temperature was 35~50¢J, the TVOC decomposition efficiency slightly increased with reaction temperature, however, when the reaction temperature went up to 55¢J, the TVOC decomposition efficiency increased only slightly, but did not increased linearly. Combination of photocatalysis and ozone oxidation system performance test results showed that ozone could decompose approximately 34% VOCs, and followed by the photocatalytical reaction of residual pollutants, achieving an overall decomposition efficiency of about 75%; while photocatalytic reaction can remove 64% of TVOCs and followed by O3 for the decomposition of residual pollutants, achieving an overall decomposition efficiency up to 94%. It showed that the combined UV/TiO2+O3 system could effectively remove VOCs in the cooking oil fume from the exhaust of restaurants. By using GC/MS to qualitatively analyze the speciation of TVOCs from cooking oil fume before and after UV/TiO2/O3, the results showed that the composition of VOCs had a decreasing trend. The peak area and dilution factor were applied to estimate the decomposition efficiency of different VOCs species. The decomposition efficiencies of pentane, 2-acrolein, acrolein, heptane, pentanal, hexanal, 2-hexenal, heptanal, heptenal and ethylhexenal were 56.21%, 72.88%, 51.33%, 32.23%, 59.04%, 69.22%, 73.53%, 41.37%, 92.57%, and 96.02%. Finally, a Langmuir-Hinshelwood kinetic model was applied to simulate the photocatalytic decomposition efficiency with the initial concentration of cooking oil fume. Model simulation results showed that the reaction rate increased with the initial TVOCs concentration. However, when TVOCs concentration increased gradually, the reaction rate became constant since the activated sites on the photocatalyst¡¦s surface was limited and cannot allow more VOC molecules diffuse to the activated sites for further photocatalytic reaction.
376

Wet Scrubbing and Activated-carbon Adsorption of Odorous Compounds in Vented Gases from Food-cooking Operations

Chen, Cheng-wei 26 June 2006 (has links)
In this study, wet scrubbing and activated-carbon adsorption technologies were tested to investigate their abilities to remove total hydrocarbons (THCs) and other odorous compounds in the effluent gas from food-cooking operations such as frying, toasting, grilling, and steaming. A full-scale scrubber (gas-liquid contacting cross section 0.58 m¡Ñ0.50 m, height 0.80 m) was used in the present study for testing its performance on removing odorous compounds from a gas stream of 102 m3/min drawn from a Japanese-type grilling restaurant located in the Kaohsiung city. The scrubbing liquid had a flow rate of 67.2 L/min which is equivalent to a liquid/gas ratio of (L/G) 0.0065 m3 liquid/(m3 gas). Tap water, aqueous sodium hypochlorite solution, and aqueous hydrogen peroxide solution were used as scrubbing liquids. For the activated carbon tests, a 2-cm i.d. glass column packed with 20 g activated carbon which gives a packing height of 10.5 cm was used to obtain the adsorption isotherms by introducing a 15 L/min gas stream drawn from an oven toasting sausage. The gas flow resulted in a superficial gas velocity of 1.06 m/s over the cross section of the column. In addition, a pilot-scale adsorption unit (cross section 0.50 m sq., packed with 30 kg granular activated carbon) was installed for the adsorption test. A gas flow drawn from a vent of a restaurant kitchen cooking Chinese-type food was introduced into the pilot adsorber. A flow rate of 12.6 m3/min was used and the superficial gas velocity was 0.84 m/s. Results indicate that THC and odor (sensory test) removals of 15-35 and 35-65% were obtained, respectively, form the scrubbing test. There was no significant difference in the performance by using one of water or the two aqueous chemical solutions as the scrubbing liquor. Most of the characteristic food-grilling and flavoring smells were removed by the scrubber and some bitter smells like burnt carbon were found in the scrubbed gas. High moisture contents (around 95% in relative humidity) of the vent gas from the sausage-toasting oven resulted in a significant reduction in the activated carbon adsorption capacity for THCs from the tested gas. From results of the pilot-scale adsorption test, THC removals of 60-80% form the vent gas (around 50-60% in relative humidity) of the Chinese-type kitchen were found during the initial adsorption time of 0-50 hr. A long time (200 hr) operation resulted in a decrease in the THC removal efficiency. However, the adsorber exhibited as an odor equalization unit by reducing peaks of the odor emissions from the kitchen. Characteristic odors from various food cooking operations were reduced by the adsorber. It was estimated that a total of around NT$ 57 is required for the full-scale scrubber for treating the gas flow of 102 m3/min for an operation time of 7 hr per day, and the cost is equivalent to NT$ 1.33/(1,000 m3 gas). The cost for the activated carbon adsorption unit of 13 m3/min was estimated to be NT$ 134 for 8 hr per streaming day. The unit cost is NT$ 22.1/(1,000 m3 gas).
377

Production Of Chips And Crisp From Jerusalem Artichoke

Baltacioglu, Cem 01 February 2012 (has links) (PDF)
Jerusalem artichoke has been cultivated in various regions without any special breeding technique. On the other hand, in food industry it does not have a wide usage area. Hence, in food industry its use as a potato substitute in some products is believed to be increasing its economical value. As a first attempt chips and crisps produced from Jerusalem artichoke was analyzed for texture, sensory, color, oil and moisture content. Jerusalem artichoke chips were fried in a bench top deep fat fryer for 120s, 180s and 240s at 160&deg / C, 170&deg / C, 180&deg / C and 190&deg / C. When microwave oven was used samples were cooked for 60s, 75s, 90s, 105s, 120s, 135s and 150s at 600 Watt and 900 Watt. Rheological properties of Jerusalem artichoke puree were investigated and Xanthan gum (2%wb) and sodium metabisulphite (1%wb) added for the desired puree consistence and color. After the production of puree Jerusalem artichoke flour was produced and water added to this flour then dough obtained again. Rheological behaviour of the original puree and these prepared from the containing 1- 4.5 and 1 - 5.0 part water were quite similar. In the light of the experimental results obtained as frying temperature and treatment time increased, moisture content and lightness of the Jerusalem artichoke products have decreased but a*and b* values, hardness, fracture and oil content increased. The best results for frying of Jerusalem artichoke seem to be 180&deg / C with about 240s treatment time for the chips and the same temperature for 180s for the crisps. As microwave power level and duration of treatment increased, moisture content and lightness of the microwave cooked Jerusalem artichoke products have decreased, but a* and b* values increased. Hardness and fracturability values of the products first increased with time and then decreased. When microwave oven was used, the best results were obtained for about 105s treatment time at 600W for the Jerusalem artichoke chips and about 60s processing time at 900W for the crisp. Since treatment time for cooking was significantly reduced when microwave cooking was used, this method could be recommended as an alternative to conventional deep fat frying, as oil is not used as well.
378

Effect of different marinade treatments on survival and morphology of pathogens in beef jerky

Khurana, Sandeep K., Clarke, Andrew Douglas. January 2009 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on December 29, 2009). Thesis advisor: Dr. Andrew D. Clarke. Includes bibliographical references.
379

"160°F for your family" an emotions-based approach to motivating women in WIC to use a food thermometer in ground beef patties /

Erickson, Amy Teresa. January 2009 (has links) (PDF)
Thesis (M.S. in human nutrition)--Washington State University, December 2009. / Title from PDF title page (viewed on Jan. 8, 2010). "College of Pharmacy." Includes bibliographical references (p. 93-101).
380

Chinese Cuisine Training Institute = Zhonghua chu yi xue yuan /

Yau, Kei-wai. January 2000 (has links)
Thesis (M. Arch.)--University of Hong Kong, 2000. / Includes special study report entitled: Re-capturing the lost urban space. Includes bibliographical references.

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