Search results for: freeze dryer
112 Comparative Syudy Of Heat Transfer Capacity Limits of Heat Pipe
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also observed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 376111 Heat Pipe Thermal Performance Improvement in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is a simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of the heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force, the liquid phase flows to evaporator section. In HVAC systems, the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally, heat pipes have three main sections: condenser, adiabatic region, and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In the present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of the heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances its heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, CFD simulation
Procedia PDF Downloads 495110 Heat Pipes Thermal Performance Improvement in H-VAC Systems Using CFD Modeling
Authors: M. Heydari, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 444109 Improve Heat Pipe Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
A heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At a hot surface of the heat pipe, the liquid phase absorbs heat and changes to the vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to the liquid phase. Due to gravitational force the liquid phase flows to the evaporator section. In HVAC systems, the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses the heater, humidifier, or dryer is a suitable nominate for the utilization of heat pipes. Generally, heat pipes have three main sections: condenser, adiabatic region, and evaporator. Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In the present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of the heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian-Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances its heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 436108 Improvement of Heat Pipe Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.Keywords: heat pipe, HVAC system, grooved heat pipe, CFD simulation
Procedia PDF Downloads 425107 Improvement of Heat Pipes Thermal Performance in H-VAC Systems Using CFD Modeling
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 364106 Bioactive Compounds and Antioxidant Capacity of Instant Fruit Green Tea Powders
Authors: Akanit Pisalwadcharin, Komate Satayawut, Virachnee Lohachoompol
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Green tea, mangosteen and pomegranate contain high levels of bioactive compounds which have antioxidant effects and great potential in food applications. The aim of this study was to produce and determine catechin contents, total phenolic contents, antioxidant activity and phenolic compounds of two instant fruit green tea powders which were green tea fortified with mangosteen juice and green tea fortified with pomegranate juice. Seventy percent of hot water extract of green tea was mixed with 30% of mangosteen juice or pomegranate juice, and then spray-dried using a spray dryer. The results showed that the drying conditions optimized for the highest total phenolic contents, catechin contents and antioxidant activity of both powders were the inlet air temperature of 170°C, outlet air temperatures of 90°C and maltodextrin concentration of 30%. The instant green tea with mangosteen powder had total phenolic contents, catechin contents and antioxidant activity of 19.18 (mg gallic acid/kg), 85.44 (mg/kg) and 4,334 (µmoles TE/100 g), respectively. The instant green tea with pomegranate powder had total phenolic contents, catechin contents and antioxidant activity of 32.72 (mg gallic acid/kg), 156.36 (mg/kg) and 6,283 (µmoles TE/100 g), respectively. The phenolic compounds in instant green tea with mangosteen powder comprised of tannic acid (2,156.87 mg/kg), epigallocatechin-3-gallate (898.23 mg/kg) and rutin (13.74 mg/kg). Also, the phenolic compounds in instant green tea with pomegranate powder comprised of tannic acid (2,275.82 mg/kg), epigallocatechin-3-gallate (981.23 mg/kg), rutin (14.97 mg/kg) and i-quercetin (5.86 mg/kg).Keywords: green tea, mangosteen, pomegranate, antioxidant activity
Procedia PDF Downloads 366105 Comparative Study of Heat Transfer Capacity Limits of Heat Pipes
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved Heat pipe, heat pipe limits
Procedia PDF Downloads 421104 Variability of Climatic Elements in Nigeria Over Recent 100 Years
Authors: T. Salami, O. S. Idowu, N. J. Bello
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Climatic variability is an essential issue when dealing with the issue of climate change. Variability of some climate parameter helps to determine how variable the climatic condition of a region will behave. The most important of these climatic variables which help to determine the climatic condition in an area are both the Temperature and Precipitation. This research deals with Longterm climatic variability in Nigeria. Variables examined in this analysis include near-surface temperature, near surface minimum temperature, maximum temperature, relative humidity, vapour pressure, precipitation, wet-day frequency and cloud cover using data ranging between 1901-2010. Analyses were carried out and the following methods were used: - Regression and EOF analysis. Results show that the annual average, minimum and maximum near-surface temperature all gradually increases from 1901 to 2010. And they are in the same case in a wet season and dry season. Minimum near-surface temperature, with its linear trends are significant for annual, wet season and dry season means. However, the diurnal temperature range decreases in the recent 100 years imply that the minimum near-surface temperature has increased more than the maximum. Both precipitation and wet day frequency decline from the analysis, demonstrating that Nigeria has become dryer than before by the way of rainfall. Temperature and precipitation variability has become very high during these periods especially in the Northern areas. Areas which had excessive rainfall were confronted with flooding and other related issues while area that had less precipitation were all confronted with drought. More practical issues will be presented.Keywords: climate, variability, flooding, excessive rainfall
Procedia PDF Downloads 384103 Determination of Resistance to Freezing of Bonded Façade Joint
Authors: B. Nečasová, P. Liška, J. Šlanhof
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Verification of vented wooden façade system with bonded joints is presented in this paper. The potential of bonded joints is studied and described in more detail. The paper presents the results of an experimental and theoretical research about the effects of freeze cycling on the bonded joint. For the purpose of tests spruce timber profiles were chosen for the load bearing substructure. Planks from wooden plastic composite and Siberian larch are representing facade cladding. Two types of industrial polyurethane adhesives intended for structural bonding were selected. The article is focused on the preparation as well as on the subsequent curing and conditioning of test samples. All test samples were subjected to 15 cycles that represents sudden temperature changes, i.e. immersion in a water bath at (293.15 ± 3) K for 6 hours and subsequent freezing to (253.15 ± 2) K for 18 hours. Furthermore, the retention of bond strength between substructure and cladding was tested and strength in shear was determined under tensile stress. Research data indicate that little, if any, damage to the bond results from freezing cycles. Additionally, the suitability of selected group of adhesives in combination with timber substructure was confirmed.Keywords: adhesive system, bonded joints, wooden lightweight façade, timber substructure
Procedia PDF Downloads 391102 Improve Heat Pipes Thermal Performance In H-VAC Systems Using CFD Modeling
Authors: A. Ghanami, M.Heydari
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator. Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.used in the abstract.Keywords: Heat pipe, HVAC system, Grooved Heat pipe, Heat pipe limits.
Procedia PDF Downloads 482101 Colour Formation and Maillard Reactions in Spray-Dried Milk Powders
Authors: Zelin Zhou, Timothy Langrish
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Spray drying is the final stage of milk powder production. Traditionally, the quality of spray-dried milk powders has mainly been assessed using their physical properties, such as their moisture contents, while chemical changes occurring during the spray drying process have often been ignored. With growing concerns about food quality, it is necessary to establish a better understanding of heat-induced degradation due to the spray-drying process of skim milk. In this study, the extent of thermal degradation for skim milk in a pilot-scale spray dryer has been investigated using different inlet gas temperatures. The extent of heat-induced damage has been measured by the formation of advanced Maillard reaction products and the loss of soluble proteins at pH 4.6 as assessed by a fluorometric method. A significant increase in the extent of thermal degradation has been found when the inlet gas temperature increased from 170°C to 190°C, suggesting protein unfolding may play an important role in the kinetics of heat-induced degradation for milk in spray dryers. Colour changes of the spray-dried skim milk powders have also been analysed using a standard lighting box. Colourimetric analysis results were expressed in CIELAB colour space with the use of the E index (E) and the Chroma (C) for measuring the difference between colours and the intensity of the colours. A strong linear correlation between the colour intensity of the spray-dried skim milk powders and the formation of advanced Maillard reaction products has been observed.Keywords: colour formation, Maillard reactions, spray drying, skim milk powder
Procedia PDF Downloads 185100 Study on Heat Transfer Capacity Limits of Heat Pipe with Working Fluids Ammonia and Water
Authors: M. Heydari, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region, and evaporator. Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In the present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.used in the abstract.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 40099 Improving Oxidative Stability of Encapsulated Krill and Black Cumin Oils and its Application in Functional Yogurt
Authors: Tamer El-Messery, Beraat Ozcelik
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This study aimed to produce functional yogurt supplemented with microencapsulated krill oil as a source of omega 3, which is known, to maintain the normal brain function, reduce the risk of cancer, and preventing cardiovascular disease. Krill oil was mixed with black cumin oil (1:1) in order to increase its oxidative stability. β-caroteine (10 mg/100 ml) was used as a standard antioxidant. Maltodextrin (MD) was mixed with whey protein concentrate (WPC) and gum Arabic (GA) at the ratio of 8:2:0.5 ratios and used for microencapsulation of single or mixed oils. The microcapsules were dried by freeze and spray drying in order to maximize encapsulation efficiency and minimize lipid oxidation. The feed emulsions used for particle production were characterized for stability, viscosity and particle size, zeta potential, and oxidative stability. The oxidative stability for mixed krill oil and black cumin oil was the highest. The highest encapsulation efficiency was obtained using spray drying, which also showed the highest oxidative stability. The addition of encapsulated krill and black cumin oils (1:1) powder in yogurt manufacture reduced slightly effects on the development of acidity, textural parameters, and water holding capacity of yogurt as compared to control.Keywords: Krill oil, black cumin oil, micro-encapsulation, oxidative stability, functional yogurt
Procedia PDF Downloads 10798 Polygeneration Solar Air Drying
Authors: Binoy Chandra Sarma, S. K. Deb
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Over 85% of industrial dryers are of the convective type with hot air or direct flue gases as the drying medium. Over 99% of the applications involve removal of water. In this study, the performance of a solar air heater with the recovery of the absorbed heat by the metallic concentrator sheet itself besides the normal heat accumulated by the receiver at the focus of the concentrator for generating drying air by convection at a low to medium temperature range is discussed. The system performance through thermal analysis & the performance of a model achieving the required temperature range is also investigate in this study. Over 85% of industrial dryers are of the convective type with hot air or direct flue gases as the drying medium. Over 99% of the applications involve removal of water. In this study, the performance of a solar air heater with the recovery of the absorbed heat by the metallic concentrator sheet itself besides the normal heat accumulated by the receiver at the focus of the concentrator for generating drying air by convection at a low to medium temperature range is discussed. The system performance through thermal analysis & the performance of a model achieving the required temperature range is also investigate in this study.Keywords: dryer, polygeneration, moisture, equilibrium, humidity
Procedia PDF Downloads 39697 Diversification of Sweet Potato Blends and Utilization for Malnutrition and Poverty Alleviation
Authors: Ladele Ademola A., Nkiru T. Meludu, Olufunke Ezekiel, Olaoye Taye F., Okanlowan Oluwatoyin M.
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Value addition to agricultural produce is of possible potential in reducing poverty, improving food security and malnutrition, therefore the need to develop small and micro-enterprises of sweet potato production. The study was carried out in Nigeria to determine the acceptability of blends sweet potato (Ipomea batatas) and commodities yellow maize (Zea mays), millet (Pennisetum glaucum), soybean (Glycine max), bambara groundnut (Vigna subterranean), guinea corn (Sorghum vulgare), wheat (Triticum aestivum), and roselle (Hibiscus sabdariffa) through sensory evaluation. Sweet potato (Ipomea batatas) roots were processed using two methods. The first method involved the use of a fabricated gas powered cabinet dryer to dry sulphited chips and the second method was the use of traditional sun drying method without the addition of the chemical. The blends were also assessed in terms of functional, chemical and color properties. Most acceptable blends include BAW (80:20 of sweet potato/wheat), BBC (80:20 of sweet potato/guinea corn), AAB (60:40 of sweet potato/guinea corn), YTE (100% soybean), TYG (100% sweet potato), KTN (100% wheat flour), XGP (80:20 of sweet potato/soybean), XAX (60:40 of sweet potato/wheat), LSS (100% Roselle), CHK (100% Guinea corn), and ABC (60:40% of sweet potato/ yellow maize). In addition, chemical analysis carried out revealed that sweet potato has high percentage of vitamins A and C, potassium (K), manganese (Mn), calcium (Ca), magnesium (Mg) and iron (Fe) and fibre content. There is also an increase of vitamin A and Iron in the blended products.Keywords: blends, diversification, sensory evaluation, sweet potato, utilization
Procedia PDF Downloads 50696 Effect of Saponin Enriched Soapwort Powder on Structural and Sensorial Properties of Turkish Delight
Authors: Ihsan Burak Cam, Ayhan Topuz
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Turkish delight has been produced by bleaching the plain delight mix (refined sugar, water and starch) via soapwort extract and powdered sugar. Soapwort extract which contains high amount of saponin, is an additive used in Turkish delight and tahini halvah production to improve consistency, chewiness and color due to its bioactive saponin content by acting as emulsifier. In this study, soapwort powder has been produced by determining optimum process conditions of soapwort extract by using response-surface method. This extract has been enriched with saponin by reverse osmosis (contains %63 saponin in dry bases). Büchi mini spray dryer B-290 was used to produce spray-dried soapwort powder (aw=0.254) from the enriched soapwort concentrate. Processing steps optimization and saponin content enrichment of soapwort extract has been tested on Turkish Delight production. Delight samples, produced by soapwort powder and commercial extract (control), were compared in chewiness, springiness, stickiness, adhesiveness, hardness, color and sensorial characteristics. According to the results, all textural properties except hardness of delights produced by powder were found to be statistically different than control samples. Chewiness, springiness, stickiness, adhesiveness and hardness values of samples (delights produced by the powder / control delights) were determined to be 361.9/1406.7, 0.095/0.251, -120.3/-51.7, 781.9/1869.3, 3427.3g/3118.4g, respectively. According to the quality analysis that has been ran with the end products it has been determined that; there is no statistically negative effect of the soapwort extract and the soapwort powder on the color and the appearance of Turkish Delight.Keywords: saponin, delight, soapwort powder, spray drying
Procedia PDF Downloads 25395 Effect of Cellular Water Transport on Deformation of Food Material during Drying
Authors: M. Imran Hossen Khan, M. Mahiuddin, M. A. Karim
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Drying is a food processing technique where simultaneous heat and mass transfer take place from surface to the center of the sample. Deformation of food materials during drying is a common physical phenomenon which affects the textural quality and taste of the dried product. Most of the plant-based food materials are porous and hygroscopic in nature that contains about 80-90% water in different cellular environments: intercellular environment and intracellular environment. Transport of this cellular water has a significant effect on material deformation during drying. However, understanding of the scale of deformation is very complex due to diverse nature and structural heterogeneity of food material. Knowledge about the effect of transport of cellular water on deformation of material during drying is crucial for increasing the energy efficiency and obtaining better quality dried foods. Therefore, the primary aim of this work is to investigate the effect of intracellular water transport on material deformation during drying. In this study, apple tissue was taken for the investigation. The experiment was carried out using 1H-NMR T2 relaxometry with a conventional dryer. The experimental results are consistent with the understanding that transport of intracellular water causes cellular shrinkage associated with the anisotropic deformation of whole apple tissue. Interestingly, it is found that the deformation of apple tissue takes place at different stages of drying rather than deforming at one time. Moreover, it is found that the penetration rate of heat energy together with the pressure gradient between intracellular and intercellular environments is the responsible force to rupture the cell membrane.Keywords: heat and mass transfer, food material, intracellular water, cell rupture, deformation
Procedia PDF Downloads 22194 Optimization of Hemp Fiber Reinforced Concrete for Various Environmental Conditions
Authors: Zoe Chang, Max Williams, Gautham Das
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The purpose of this study is to evaluate the incorporation of hemp fibers (HF) in concrete. Hemp fiber reinforced concrete (HFRC) is becoming more popular as an alternative for regular mix designs. This study was done to evaluate the compressive strength of HFRC regarding mix procedure. Hemp fibers were obtained from the manufacturer and hand-processed to ensure uniformity in width and length. The fibers were added to the concrete as both wet and dry mixes to investigate and optimize the mix design process. Results indicated that the dry mix had a compressive strength of 1157 psi compared to the wet mix of 985 psi. This dry mix compressive strength was within range of the standard mix compressive strength of 1533 psi. The statistical analysis revealed that the mix design process needs further optimization and uniformity concerning the addition of HF. Regression analysis revealed the standard mix design had a coefficient of 0.9 as compared to the dry mix of 0.375, indicating a variation in the mixing process. While completing the dry mix, the addition of plain hemp fibers caused them to intertwine, creating lumps and inconsistency. However, during the wet mixing process, combining water and hemp fibers before incorporation allows the fibers to uniformly disperse within the mix; hence the regression analysis indicated a better coefficient of 0.55. This study concludes that HRFC is a viable alternative to regular mixes; however, more research surrounding its characteristics needs to be conducted.Keywords: hemp fibers, hemp reinforced concrete, wet & dry, freeze thaw testing, compressive strength
Procedia PDF Downloads 20093 Counter-Current Extraction of Fish Oil and Toxic Elements from Fish Waste Using Supercritical Carbon Dioxide
Authors: Parvaneh Hajeb, Shahram Shakibazadeh, Md. Zaidul Islam Sarker
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High-quality fish oil for human consumption requires low levels of toxic elements. The aim of this study was to develop a method to extract oil from fish wastes with the least toxic elements contamination. Supercritical fluid extraction (SFE) was applied to detoxify fish oils from toxic elements. The SFE unit used consisted of an intelligent HPLC pump equipped with a cooling jacket to deliver CO2. The freeze-dried fish waste sample was extracted by heating in a column oven. Under supercritical conditions, the oil dissolved in CO2 was separated from the supercritical phase using pressure reduction. The SFE parameters (pressure, temperature, CO2 flow rate, and extraction time) were optimized using response surface methodology (RSM) to extract the highest levels of toxic elements. The results showed that toxic elements in fish oil can be reduced using supercritical CO2 at optimum pressure 40 MPa, temperature 61 ºC, CO2 flow rate 3.8 MPa, and extraction time 4.25 hr. There were significant reductions in the mercury (98.2%), cadmium (98.9%), arsenic (96%), and lead contents (99.2%) of the fish oil. The fish oil extracted using this method contained elements at levels that were much lower than the accepted limits of 0.1 μg/g. The reduction of toxic elements using the SFE method was more efficient than that of the conventional methods due to the high selectivity of supercritical CO2 for non-polar compounds.Keywords: food safety, toxic elements, fish oil, supercritical carbon dioxide
Procedia PDF Downloads 42392 Effect of Thermal Pretreatment on Functional Properties of Chicken Protein Hydrolysate
Authors: Nutnicha Wongpadungkiat, Suwit Siriwatanayotin, Aluck Thipayarat, Punchira Vongsawasdi, Chotika Viriyarattanasak
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Chicken products are major export product of Thailand. With a dramatically increasing consumption of chicken product in the world, there are abundant wastes from chicken meat processing industry. Recently, much research in the development of value-added products from chicken meat industry has focused on the production of protein hydrolysate, utilized as food ingredients for human diet and animal feed. The present study aimed to determine the effect of thermal pre-treatment on functional properties of chicken protein hydrolysate. Chicken breasts were heated at 40, 60, 80 and 100ºC prior to hydrolysis by Alcalase at 60ºC, pH 8 for 4 hr. The hydrolysate was freeze-dried, and subsequently used for assessment of its functional properties molecular weight by gel electrophoresis (SDS-PAGE). The obtained results show that increasing the pre-treatment temperature increased oil holding capacity and emulsion stability while decreasing antioxidant activity and water holding capacity. The SDS-PAGE analysis showed the evidence of protein aggregation in the hydrolysate treated at the higher pre-treatment temperature. These results suggest the connection between molecular weight of the hydrolysate and its functional properties.Keywords: chicken protein hydrolysate, enzymatic hydrolysis, thermal pretreatment, functional properties
Procedia PDF Downloads 27091 Synthesize And Physicochemical Characterization Of Biomimetic Scaffold Of Gelatin/zn-incorporated 58s Bioactive Glass
Authors: SeyedMohammad Hosseini, Amirhossein Moghanian
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The main purpose of this research was to design a biomimetic system by freeze-drying method for evaluating the effect of adding 5 and 10 mol. % of zinc (Zn)in 58S bioactive glass and gelatin (5ZnBG/G and 10ZnBG/G) in terms of structural and biological changes. The structural analyses of samples were performed by X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Also, 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide(MTT) and alkaline phosphate (ALP) activity test were carried out for investigation of MC3T3-E1cell behaviors. The SEM results demonstrated the spherical shape of the formed hydroxyapatite (HA) phases, and also HA characteristic peaks were detected by X-ray diffraction spectroscopy (XRD)after 3 days of immersion in the simulated body fluid (SBF) solution. Meanwhile, FTIR spectra proved that the intensity of P–O peaks for 5ZnBG/G was more than 10ZnBG/G and control samples. Moreover, the results of alkaline phosphatase activity (ALP) test illustrated that the optimal amount of Zn (5ZnBG/G) caused a considerable enhancement in bone cell growth. Taken together, the scaffold with 5 mol.% Zn was introduced as an optimal sample because of its higher biocompatibility, in vitro bioactivity, and growth of MC3T3-E1cellsin in comparison with other samples in bone tissue engineering.Keywords: scaffold, gelatin, modified bioactive glass, alp, bone tissue engineering
Procedia PDF Downloads 9490 Drying Kinetics of Okara (Soy Pulp) Using the Multi-Commodity Heat Pump Dryer (MCHPD)
Authors: Lorcelie B. Taclan, Jolly S. Balila, Maribel Balagtas, Eunice M. Aclan, Myrtle C. Orbon, Emson Y. Taclan, Irenea A. Centeno
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Okara (soy pulp), a by-product and waste from the production of soymilk, tufo and tokwa and soybean-based vegan food products is readily available in the university thrice a week. The Food Factory owned and managed by AUP produces these food products weekly. Generally the study was conducted to determine the drying kinetics of soya pulp using the MCHPD. Specifically, it aimed to establish the time of drying; moisture loss per hour and percent moisture content of soya pulp and to establish the dried okara as an ingredient to other foods. The MCHPD is drying equipment that has an ideal drying condition of 50.00C and 10.0% relative humidity. Fresh and wet soya pulp were weighed at 1.0 kg per tray (21 drying trays), laid on the trays lined with cheese cloth. The MCHPD was set to desired drying conditions. Weight loss was monitored every hour and calculated using standard formulas. Research results indicated that the drying time for soya pulp was 19.0 hours; the % moisture content was reduced from 87.6.0% to 9.7.0% at an average moisture loss of 3.0 g/hr. The nutritional values of okara were favorably maintained with enhanced color. The dried okara was added as an ingredient to other healthy bakery products produced by the AUP Food Factory. Making use of okara would add nutritional values to other food products and would also help waste management concerns inside the university.Keywords: okara, MCHPD, drying kinetics, nutritional values, waste management
Procedia PDF Downloads 39589 The Study of Spray Drying Process for Skimmed Coconut Milk
Authors: Jaruwan Duangchuen, Siwalak Pathaveerat
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Coconut (Cocos nucifera) belongs to the family Arecaceae. Coconut juice and meat are consumed as food and dessert in several regions of the world. Coconut juice contains low proteins, and arginine is the main amino acid content. Coconut meat is the endosperm of coconut that has nutritional value. It composes of carbohydrate, protein and fat. The objective of this study is utilization of by-products from the virgin coconut oil extraction process by using the skimmed coconut milk as a powder. The skimmed coconut milk was separated from the coconut milk in virgin coconut oil extraction process that consists approximately of protein 6.4%, carbohydrate 7.2%, dietary fiber 0.27 %, sugar 6.27%, fat 3.6 % and moisture content of 86.93%. This skimmed coconut milk can be made to powder for value - added product by using spray drying. The factors effect to the yield and properties of dry skimmed coconut milk in spraying process are inlet, outlet air temperature and the maltodextrin concentration. The percentage of maltodextrin content (15, 20%), outlet air temperature (80 ºC, 85 ºC, 90 ºC) and inlet air temperature (190 ºC, 200 ºC, 210 ºC) were conducted to the skimmed coconut milk spray drying process. The spray dryer was kept air flow rate (0.2698 m3 /s). The result that shown 2.22 -3.23% of moisture content, solubility, bulk density (0.4-0.67g/mL), solubility, wettability (4.04 -19.25 min) for solubility in the water, color, particle size were analyzed for the powder samples. The maximum yield (18.00%) of spray dried coconut milk powder was obtained at 210 °C of temperature, 80°C of outlet temperature and 20% maltodextrin for 27.27 second for drying time. For the amino analysis shown that the high amino acids are Glutamine (16.28%), Arginine (10.32%) and Glycerin (9.59%) by using HPLP method (UV detector).Keywords: skimmed coconut milk, spray drying, virgin coconut oil process (VCO), maltodextrin
Procedia PDF Downloads 33288 Contact Toxicity Effects of Different Formulations of Artemisia Absinthium Extracts on Rose Aphid
Authors: Maryam Atapour
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Chemical pesticides, which are widely used in agriculture, cause problems such as soil and water pollution, reducing biodiversity and creating pest resistance. These problems have led to increased attention to alternative and more sustainable methods such as natural-based pesticides. Herbal pesticides have been developed based on essential oils or extracts from different parts of plants, such as leaves, roots, and flowers. Herbal pesticides are compatible with the environment and can be used in integrated pest management programs. Despite the many benefits, herbal pesticides, especially essential oil-based compounds, have low durability in the environment, and their production costs are high, so the use of herbal extracts with appropriate formulations is more justified in all aspects. In the current study and based on the results of previous studies, aqueous and 70% ethanolic extract of Artemisia absinthium L. was prepared by the percolation method and formulated as an emulsion and water-soluble powder. To produce powder formulation, 20% maltodextrin was used with the spray-dryer method. Different concentrations of these compounds were sprayed on bushes infected with rose aphid Macrosiphum rosae (L.). Sampling was done randomly and the percentage of aphids’ mortality was checked. The results showed that the use of different concentrations of ethanolic extracts created a significant difference in the mortality rate of aphids, while water-soluble powder formulation caused less mortality. The current results showed that the extract of this plant has practical usability to control aphids, and with the appropriate formulation, it can be used as a good alternative to chemical pesticides.Keywords: contact toxicity, formulation, extract, aphid, Artemisia absinthium.
Procedia PDF Downloads 3687 Formulation and in Vitro Characterization of Bioactives Loaded Polymeric Nanoparticle Incorporated into Multiphase Hydrogel System for the Treatment of Infected Burn Wound
Authors: Rajni Kant Panik, Deependra Singh, Manju Singh
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Despite significant advances in the treatment of severe burn injury, infection and sepsis persist as frequent causes of morbidity and mortality for burn victims due to extensive compromise of the skin and contiguous tissue that serve as a protective barrier against microbial invasion. In the setting of a burn wound infection, Staphylococcus aureus is the most commonly isolated pathogens from bloodstream infections in burn care hospitals. We aimed to develop a biocompatible system of Poly vinyl alcohol (PVA)-sodium alginate hydrogel carrying multiple drugs- catalase and mupirocin in controlled manner for effective and complete burn wound healing. PLGA nanoparticles of Catalase and mupirocin were prepared by homogenization method and optimized system was incorporated in PVA-sodium alginate slurry. PVA-sodium alginate hydrogels were prepared by freeze thaw method. The prepared dispersion was casted into films to prepare multiphase hydrogel system and characterized by in vitro and in vivo studies. The study clearly showed the beneficial effect of antioxidant enzyme and antibiotic in the treatment of infected burn wound, as evidenced by the reduced incidence of wound infection and the shortening of healing time.Keywords: burn wound, catalase, mupirocin, wound healing
Procedia PDF Downloads 50386 Mechanical Characterization and Durability of Eco-Efficient Ultra High Performance Concrete
Authors: Valeria Corinaldesi, Nicola Generosi, Jacopo Donnini
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Ultra high performance concrete (UHPC) is an innovative material which tends to exhibit superior properties such as incredible mechanical and durability performance and non-brittleness behavior. Over the last twenty years, phenomenal advances have taken place in the research and application of UHPC. Recently, the approach is to improve UHPC sustainability by reducing its embodied energy. First of all, this goal can be achieved by reducing Portland cement dosage. In this work, an experimental investigation was carried out to characterize the mechanical behavior and durability of UHPCs prepared by reducing the cement amount by 30% in order to verify the impact of lower cement content and higher water-to-cement ratio on both mechanical performance and durability, if any. Eight different UHPC mixtures were compared, with two different cement dosages (either 1000 or 700 kg) and four different brass-coated steel fibres dosages (0 - 50 - 100 - 150 kg), in terms of 28-day compressive and flexural strengths. Then, the mixtures prepared with the lower cement content were further investigated in terms of abrasion resistance, water absorption, freezing and thawing cycles, and resistance to sulphate attack. Results obtained showed the feasibility of reducing cement dosage without compromising mechanical performance and UHPC's extraordinary durability.Keywords: abrasion resistance, durability, eco-efficiency, freeze-thawing cycles, steel fibres, sulphate exposure, sustainability, UHPC
Procedia PDF Downloads 7685 Investigation of Cytotoxic Compounds in Ethyl Acetate and Chloroform Extracts of Nigella sativa Seeds by Sulforhodamine-B Assay-Guided Fractionation
Authors: Harshani Uggallage, Kapila D. Dissanayaka
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A Sulforhodamine-B assay-guided fractionation on Nigella sativa seeds was conducted to determine the presence of cytotoxic compounds against human hepatoma (HepG2) cells. Initially, a freeze-dried sample of Nigella sativa seeds was sequentially extracted into solvents of increasing polarities. Crude extracts from the sequential extraction of Nigella sativa seeds in chloroform and ethyl acetate showed the highest cytotoxicity. The combined mixture of these two extracts was subjected to bioassay guided fractionation using a modified Kupchan method of partitioning, followed by Sephadex® LH-20 chromatography. This chromatographic separation process resulted in a column fraction with a convincing IC50 (half-maximal inhibitory concentration) value of 13.07µg/ml, which is considerable for developing therapeutic drug leads against human hepatoma. Reversed phase High-Performance Liquid Chromatography (HPLC) was finally conducted for the same column fraction, and the result indicates the presence of one or several main cytotoxic compounds against human HepG2 cells.Keywords: cytotoxic compounds, half-maximal inhibitory concentration, high-performance liquid chromatography, human HepG2 cells, nigella sativa seeds, Sulforhodamine-B assay
Procedia PDF Downloads 40184 Experimental and Numerical Determination of the Freeze Point Depression of a Multi-Phase Flow in a Scraped Surface Heat Exchanger
Authors: Carlos A. Acosta, Amar Bhalla, Ruyan Guo
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Scraped surface heat exchangers (SSHE) use a rotor shaft assembly with scraping blades to homogenize viscous fluids during the heat transfer process. Obtaining in-situ measurements is difficult because the rotor and scraping blades spin continuously inside the mixing chamber, obstructing the instrumentation pathway. Computational fluid dynamics simulations provide useful insight into the flow behavior around the scraper blades for a variety of fluids and blade geometries. However, numerical solutions often focus on the fluid dynamics and heat transfer phenomena of rotating flow, ignoring the glass-transition temperature and freezing point depression. This research studies the multi-phase fluid dynamics and freezing point depression inside the SSHE with non-isothermal conditions in a time dependent process using an aqueous solution that contains 13.5 wt.% high fructose corn syrup and CO₂. The computational results were validated with in-situ pressure, temperature, and optical spectroscopy measurements. Results from the numerical model show good quantitatively agreement with experimental values.Keywords: computational fluid dynamics, freezing point depression, phase-transition temperature, multi-phase flow
Procedia PDF Downloads 14783 Resilience of Infrastructure Networks: Maintenance of Bridges in Mountainous Environments
Authors: Lorenza Abbracciavento, Valerio De Biagi
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Infrastructures are key elements to ensure the operational functionality of the transport system. The collapse of a single bridge or, equivalently, a tunnel can leads an entire motorway to be considered completely inaccessible. As a consequence, the paralysis of the communications network determines several important drawbacks for the community. Recent chronicle events have demonstrated that ensuring the functional continuity of the strategic infrastructures during and after a catastrophic event makes a significant difference in terms of life and economical losses. Moreover, it has been observed that RC structures located in mountain environments show a worst state of conservation compared to the same typology and aging structures located in temperate climates. Because of its morphology, in fact, the mountain environment is particularly exposed to severe collapse and deterioration phenomena, generally: natural hazards, e.g. rock falls, and meteorological hazards, e.g. freeze-thaw cycles or heavy snows. For these reasons, deep investigation on the characteristics of these processes becomes of fundamental importance to provide smart and sustainable solutions and make the infrastructure system more resilient. In this paper, the design of a monitoring system in mountainous environments is presented and analyzed in its parts. The method not only takes into account the peculiar climatic conditions, but it is integrated and interacts with the environment surrounding.Keywords: structural health monitoring, resilience of bridges, mountain infrastructures, infrastructural network, maintenance
Procedia PDF Downloads 77