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Oven
Kinds of Oven Selected AbstractsHEAT TRANSFER COEFFICIENT FOR COOKIE SHAPED OBJECTS IN A HOT AIR JET IMPINGEMENT OVENJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2001N. NITIN ABSTRACT Correlations for average heat transfer coefficient for cookie shaped objects in a hot air jet impingement oven were obtained using aluminum cookie models. The study was carried out in a pilot plant scale hot air jet impingement oven. The effects of individual cookie position, presence of surrounding cookies, air velocity, air temperature and rotation of the oven plate on average surface heat transfer coefficient were investigated. The value of the heat transfer coefficient ranged between 100,225 W/m2K and was found to be a strong function of jet air velocity. The impact of surrounding cookies on the heat transfer coefficient was more for smaller cookies, which had larger cookie-to-cookie spacing. [source] EFFECTS OF OVEN HUMIDITY ON FOODS BAKED IN GAS CONVECTION OVENS,JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2004J. XUE ABSTRACT Bread, cakes, and cookies were baked in direct- and indirect-gas fired, foodservice style convection ovens. Oven humidity was varied by including different numbers of perlite and water dummy loads during baking. Oven, product, and dummy temperatures were continuously recorded during baking, as was oven humidity. The properties of the finished baked foods were measured. Increased oven humidity resulted in products with higher yield, greater volume or spread, lighter color, and reduced firmness. [source] Modeling Cooking Time to Inactivate Salmonella in Chicken Leg Quarters Cooked in an Air,Steam Impingement OvenJOURNAL OF FOOD SCIENCE, Issue 5 2006Tareq M. Osaili ABSTRACT:, Inadequate cooking of poultry products may lead to human foodborne infections. The use of mathematical models that describe heat transfer during cooking of chicken leg quarters may help in developing safer food products and minimizing time for cooking. The objective of this study was to develop regression models that predict cooking time required to reach internal temperatures of 71.1, 73.9, 76.7, and 82.2 °C in chicken leg quarters. Samples that had different weights, thicknesses, and initial internal temperatures were cooked in an air,steam impingement oven at temperature of 232.2 °C, humidity of 60%, and air velocity of 1.4 m/min. A thermocouple probe (type K) connected with a data acquisition system was inserted into the coldest point of each chicken leg quarter. Samples were cooked until they reached an internal temperature higher than 82.2 °C. The collected data of each sample in the data acquisition system were used to develop regression models that depend on sample weight, thickness, and initial temperature in predicting cooking times. Sample weight, thickness, and initial internal temperature had significant effects on the cooking time. The results of these models would be helpful for ready-to-eat poultry processors to meet lethality performance standards, and ensuring the safety and quality of skin on, bone in chicken leg quarters cooked via air,steam impingement ovens. [source] Thermal Inactivation of Salmonella Senftenberg and Listeria innocua in Beef/Turkey Blended Patties Cooked via Fryer and/or Air Convection OvenJOURNAL OF FOOD SCIENCE, Issue 5 2002R.Y. Murphy ABSTRACT: Beef/turkey blended patties, containing 107 to 108 cfu/g of Salmonella Senftenberg or Listeria innocua, were battered and breaded. The effect of frying (177 °C) and air convection cooking (288 °C) on thermal inactivation of S. Senftenberg and L. innocua was evaluated. A model was obtained to correlate product internal temperature with frying and oven cooking time. Cooking method significantly affected thermal history and subsequently the thermal inactivation of S. Senftenberg and L. innocua. The effect of frying time interacted with oven cooking time. Increasing frying time reduced the oven cooking time. Mathematical models were developed to correlate the survival rate of S. Senftenberg or L. innocua with frying and oven cooking time. [source] Sintering of Partially Stabilized Zirconia by Microwave Heating Using ZnO,MnO2,Al2O3 Plates in a Domestic Microwave OvenJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2000Satoru Fujitsu Partially stabilized zirconia (PSZ) powders were fully densified by microwave heating using a domestic microwave oven. Pressed powder compacts of PSZ were sandwiched between two ZnO,MnO2,Al2O3 ceramic plates and put into the microwave oven. In the first step, PSZ green pellets were heated by self-heating of ZnO,MnO2,Al2O3 ceramics (1000°C). In the second step, the heated PSZ pellets absorbed microwave energy and self-heated up to a higher temperature (1250°C), leading to densification. The density of PSZ obtained by heating in the microwave oven for 16 min was 5.7 g/cm3, which was approximately equal to the density of bodies sintered at 1300°C for 4 h or 1400°C for 16 min by the conventional method. The average grain size of the sample obtained by this method was larger than the average grain size of samples sintered by the conventional method with a similar heating process. [source] Something from the Oven: Reinventing Dinner in 1950s AmericaTHE JOURNAL OF POPULAR CULTURE, Issue 6 2005Martha L. Finch No abstract is available for this article. [source] Single-Mode Microwave Ovens as New Reaction Devices: Accelerating the Living Polymerization of 2-Ethyl-2-OxazolineMACROMOLECULAR RAPID COMMUNICATIONS, Issue 22 2004Frank Wiesbrock Abstract Summary: The ring-opening cationic polymerization of 2-ethyl-2-oxazoline was performed in a single-mode microwave reactor as the first example of a microwave-assisted living polymerization. The observed increase in reaction rates by a factor of 350 (6 h,,,1 min) in the range from 80 to 190,°C could be attributed solely to a temperature effect as was clearly shown by control experiments and the determined activation energy. Because of the homogenous microwave irradiation, the polymerization could be performed in bulk or with drastically reduced solvent ratios (green chemistry). Monomer conversion, represented by the ratio ln{[M0]/[Mt]}, plotted against time for six temperatures in the range from 80 to 180,°C, and polymerization reaction vials, showing an increase in yellow color for those reactions performed (well) above and below 140,°C, indicating side reactions. [source] Induction Ovens and Electromagnetic Interference:PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7p1 2003What is the Risk for Patients with Implanted Pacemakers? Electromagnetic fields may interfere with normal pacemaker function. Despite the introduction of modern pacemakers and bipolar lead systems, electromagnetic interference (EMI) still remains to be a concern during daily lives when patients are exposed to cellular phones, electronic security systems, and several household appliances. The aim of this study was to evaluate potential EMI risk of induction ovens, which are increasingly used in private households. The study included 40 consecutive patients (22 men, 18 women; age73 ± 11 years) with implanted DDD, VVI, VDD, and AAI pacemaker systems. The pacemakers were programmed to unipolar sensing and pacing. Sensitivity remained unchanged, if the measured sensing threshold was more than twice the programmed value; otherwise, it was set at half of the measured sensing threshold. Patients were placed in a sitting position at the closest possible distance of about 20 cm between two cooking pots and pacemaker bending the upper part of the body slightly over the induction oven. The energy was increased stepwise to the maximum. One pot was removed and placed again at the highest oven level. Potential interference was monitored continuously. The study showed no incidence of pacemaker malfunction during the entire test while the patients with intrinsic cardiac rhythms were exposed to the induction oven at varying energy strengths. Likewise, there was no external interference when the patients were paced at heart rates of 10,15 beats/min above their heart rates. The programmed parameters remained unchanged after the study. In conclusion, this study shows no EMI risk of an induction oven in patients with bipolar or right-sided unipolar pacemakers. (PACE 2003; 26[Pt. I]:1494,1497) [source] Ultrastructural preservation of rat embryonic dental tissues after rapid fixation and dehydration under microwave irradiationEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2000Luciana F. Massa Adequate preservation of the cells and matrix of mineralising tissues remains difficult, as organic components and initial mineral deposits may be lost during conventional processing for electron microscopy. In this study, we have reduced significantly the processing time using microwave irradiation. Rat molar tooth germs were fixed in 4% glutaraldehyde+4% formaldehyde with 0.1 M sodium cacodylate in a laboratory microwave oven for two periods of 20 s with a maximal temperature of 37°C. After conventional washing and post-fixation, specimens were dehydrated in graded ethanols under microwave irradiation for a total of 7 min 20 s. For comparison, some specimens were processed by conventional methods. After embedding, ultrathin sections were examined by electron microscopy. In differentiating ameloblasts and odontoblasts, plasma membranes, mitochondria, rough endoplasmic reticulum, the Golgi complex, together with all other cytoplasmic organelles exhibited excellent preservation. Microtubules, microfilaments and coated vesicles were particularly evident. Crystal-like mineral deposits were conspicuously present in relation to dentine matrix vesicles and collagen fibrils as well as in enamel matrix. The matrix of forming enamel had a globular electron-lucent appearance. It is concluded that this is a rapid method which provides a preserved or even improved morphology. [source] Processing of urea-formaldehyde-based particleboard from hazelnut shell and improvement of its fire and water resistanceFIRE AND MATERIALS, Issue 8 2009M. Gürü Abstract The purpose of this study was to manufacture urea-formaldehyde-based particleboard from hazelnut shell and eliminate its disadvantages such as flammability, water absorption, swelling thickness by using fly ash and phenol-formaldehyde. Synthesized urea-formaldehyde and grained hazelnut shells were blended at different ratios ranging from 0.8 to 3.2 hazelnut shell/urea-formaldehyde and dried at 70°C in an oven until constant weight was reached. In addition, other parameters affecting polymer composite particleboard from hazelnut shell and urea-formaldehyde were investigated to be the amount of fly ash, amount of phenol formaldehyde and the effects of these parameters on bending stress, limit oxygen index, water absorption capacity and swelling in the thickness. The optimization results showed that the maximum bending strength was 4.1N/mm2, at urea-formaldehyde ratio of 1.0, reaction temperature of 70°C, reaction time of 25,min, hazelnut shell/urea-formaldehyde resin of 2.4 and mean particle size of 0.1,mm. Although the limited oxygen index and smoke density of composite particleboard without fly ash has 22.3 and 1.62, with fly ash of 16% (w/w) according to the filler has 38.2 and 1.47, respectively. Water absorption and increase in the swelling thickness exponentially decreased with increasing phenol formaldehyde. Copyright © 2009 John Wiley & Sons, Ltd. [source] An evaluation of the self-heating hazards of cerium(IV) nitrated treated towels using differential scanning calorimetry and thermogravimetric analysisFIRE AND MATERIALS, Issue 6 2007J. R. Hartman Abstract This study measured the Arrhenius kinetic parameters and heat of reaction using thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) for the combustion of untreated towels and towels treated with cerium(IV) nitrate. These parameters were used to calculate the self-heating parameters, M and P (Self-heating: Evaluating and Controlling the Hazard. Her Majesty's Stationery Office: London, 1984) and the critical pile sizes of the towels at several temperatures. The results from the TGA/DSC experiments support the conclusions by Beyler et al. (Fire and Materials 2005; 30:223,240) that the cerium(IV) nitrate treatment of towels significantly enhances the ignitability of the towels but that self-heating is not a hazard for normal temperature storage scenarios other than bulk storage. It was found that the kinetic reaction data measured by TGA and DSC are only useful for predicting the specific reaction hazard for materials stored above 100°C. A comparison of the self-heating parameters measured by oven and kinetic reaction data methods for a number of materials suggests that the kinetic reaction data overestimate the critical pile size at temperatures below 100°C. In addition, it was found that the kinetic reaction data measured by TGA can be used to determine the relative self-heating hazards for modified materials. TGA testing with towels saturated with a 0.5 N solution of cerium(IV) nitrate (Ce(NO3)4) in a 2.0 N solution of nitric acid, a 2.0 N solution of sodium nitrate in 2.0 N nitric acid and simple 2.0 N nitric acid, showed that the sodium nitrate and nitric acid treated samples reacted at the same temperatures as the untreated towels, while cerium(IV) nitrate markedly reduced the reaction temperature. These tests clearly point to the importance of the cerium(IV) ion as an oxidizing agent. Thus, the TGA testing provided in a matter of days, insights that would have required months of oven testing. Copyright © 2006 John Wiley & Sons, Ltd. [source] Metal Corrosion and its Impact on Glass Tempering Furnace DesignINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 5 2010Peter Tiernan A reliable well-designed tempering furnace is considered to be the cornerstone of any modern glass-processing facility. This paper addresses a series of engineering anomalies encountered during the commissioning of such a glass-processing furnace. Following the installation of a furnace in a European facility, small black deposits were noticed on both the silica-fused rollers used to transport the glass through the hearth of the furnace and on the processed glass surface itself. EDAX and scanning electron microscopy investigations indicated conclusively that the deposits were primarily constituted of sodium sulfate and trace elements consistent with stainless steel (chromium, iron, and nickel). Traditionally, high-density glass fiber was used to insulate the roof walls and side walls of tempering furnaces; however, it was noticed in this particular case that rolled stainless steel sheeting (SS316) was used. Chemical and X-ray diffraction analyses were used to pinpoint the origin of the deposits. It was determined that poor material selection choices taken during the design stage of the furnace in question were at fault. The combination of stainless steel and sulfur dioxide (SO2 is used as a lubricant to prevent scuffing) at elevated temperatures (>650°C) generated droplets of sodium sulfate, which condensed due to the convectional flow of the heat currents within the oven. These droplets scorched the glass surface and destroyed the fused silica rollers. As a recommendation, the usage of stainless steel and other nonrefractory metals should be avoided in the design of any future glass tempering furnaces. [source] Effect of different precooking methods on chemical composition and lipid damage of silver carp (Hypophthalmichthys molitrix) muscleINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 10 2010Mahmood Naseri Summary The influence of three precooking methods (steaming, oven-baking and microwave-cooking) on the chemical composition and lipid quality of silver carp fillets was evaluated. The changes in protein, fat and moisture were found to be significant for all the treatments (P , 0.05). The iron content in the samples subjected to steam-cooking increased; however, the other precooking methods did not change the mineral contents (P , 0.05). The free fatty acid content of the fillets did not change by the different precooking methods, while thiobarbituric acid (TBA) values increased for oven- and microwave-cooked fillets and remained constant in the steam-cooked samples. Conjugated diene and browning colour formation levels significantly increased in the oven-baked fillets. Oven-baking and microwave-cooking marginally affected the fatty acid composition of the silver carp. On comparing the raw and precooked fillets, steam-cooking was found to be the best precooking method on retaining nutritional constituents. [source] Glass transition behaviour of fructoseINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2004Vinh Truong Summary The glass transition temperature and the second transition (the endothermic change between the glass transition and melting temperatures) of fructose were studied. The thermal history strongly affected both transitions of fructose. Storage for 10 days at 22 °C increased the dynamic glass transition temperature from 16 to 25 °C and decreased the second transition of fructose from 110 to 98 °C in the first differential scanning calorimetric (DSC) scan. The amplitude of the second transition increased slightly with storage time and reached 260% of the first transition for vacuum oven dried samples. The effect of thermal history on the glass transition temperature of fructose can be removed by scanning the sample in a DSC to 130 °C. The effects of water content, glucose and sucrose on the two transitions were also investigated. [source] The effects of ingredients on popcorn popping characteristicsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2004Mehmet Ceylan Summary Response surface methodology was used to evaluate the effects of ingredients on popcorn popping characteristics. The effects of different ingredients on the expansion volume and unpopped kernel ratio of popcorn in a conventional popper and a microwave oven were evaluated and optimized by response surface methodology. The regression models were significant and had R2 value in the range of 0.919,0.956. The optimum levels of ingredients for microwave popping were 4.4% salt, 5.9% vegetable oil, 0% sodium bicarbonate and 16.4% butter, this formulation giving an expansion volume of 33.1 mL g,1. In the case of conventional popping, the maximum expansion volume of 37.3 mL g,1 was obtained for 3.5% salt, 6% vegetable oil, 0.10% sodium bicarbonate and 12.9% butter. [source] Effect of thermal treatment of incubated potato juice on the formation of Maillard volatilesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2003Stephen J. Davids Summary Potato juice samples, obtained from potatoes stored at different temperatures (0,24 °C) and times (8,20 weeks), were incubated (45,57 °C for 42 h) with or without commercial proteases. The samples were then used for thermal browning experiments by placing in either a heated oven at 125 °C overnight or in an autoclave at 132 or 121 °C for 1 h, these experiments promoted the occurrence of the Maillard reaction. After the heat treatment step, all samples were extracted with methylene chloride and analysed by gas chromatography/mass spectrometry. The data indicated that, by subjecting the potato juice to thermal treatments, a wide variety of volatiles generated by the Maillard were produced and these are known to be associated with specific flavour notes, examples are alkyl and acetyl pyrazines, piperazinediones, furans and pyrroles. These findings suggest that the study of potato juice extract as a new medium for flavour development, in particular in those applications which presently use malt, coffee, soybean, meat and yeast extracts, is a worthwhile endeavour. [source] Changes in the fatty acid composition of vegetable oils in model doughs submitted to conventional or microwave heatingINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2003Francesco Caponio Summary An experimental investigation ascertained the variation of the contents of saturated, unsaturated and polyenoic fatty acids, as well as of the trans -isomers of unsaturated fatty acids, in different vegetable oils (virgin olive oil, refined sunflower, refined peanut) submitted to either conventional or microwave heating. The results obtained showed that heat treatment causes a worsening of the nutritional quality of the fatty fraction. As a consequence, the contents of unsaturated and polyenoic fatty acids decreased, with greater variations in the oils heated by microwave than by a conventional oven, while the saturated fatty acid contents did not change substantially. The heat treatments also caused an increase in the trans -isomers of unsaturated fatty acids and this was more evident after microwave treatment. [source] A preliminary study on bladder-assisted rotomolding of thermoplastic polymer compositesADVANCES IN POLYMER TECHNOLOGY, Issue 1 2007A. Salomi Abstract In this preliminary work, a new process is examined for manufacturing hollow parts from continuous fiber-reinforced thermoplastic polymer. The new process combines the basic idea of bag forming (or bladder-assisted forming) with the rotation of the mold for the processing of thermoplastic matrix composites. A pressurized membrane is used to compact the composite on the inner wall of a mold, which is placed inside a forced convection oven. The mold is removed from the oven for the cooling stage. The process was initially developed by using a thermoplastic pre-preg obtained using yarns of commingled E-glass fibers with isotactic polypropylene (iPP). A preliminary characterization of the thermoplastic composite showed that the material can be consolidated with pressures as low as 0.01 MPa, which is readily achievable with the process of this study. The design of the mold and membrane was carried out on the basis of both structural analysis of the aluminum shell and thermal analysis of the mold. The mold thickness is of great importance with respect to both the maximum pressure allowed in the process and the overall cycle time. Molding was performed on stacks of three and six layers of yarn, varying the applied pressure between 0.01 and 0.05 MPa and maximum temperature of the internal air between 185°C and 215°C. The composite shells obtained under different processing conditions were characterized in terms of physical and mechanical properties. Mechanical properties comparable with those obtained by compression molding and vacuum bagging were obtained. The maximum values obtained are 12.1 GPa and 290 MPa for the flexural modulus and the flexural strength, respectively. Furthermore, the results obtained show that mechanical properties improve with increasing the pressure during the cycle and with the maximum temperature used in the process. © 2007 Wiley Periodicals, Inc. Adv Polym Techn 26:21,32, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20085 [source] Ozone cracking and flex cracking of crosslinked polymer blend compoundsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2007M. F. Tse Abstract Ozone cracking and flex cracking of crosslinked elastomer blends of brominated isobutylene/para -methylstyrene copolymer (BIMSM) and unsaturated elastomers, such as polybutadiene rubber (BR) and natural rubber (NR), are studied. This saturated BIMSM elastomer, which is a terpolymer of isobutylene, para -bromomethylstyrene, and para -methylstyrene, functions as the ozone-inert phase of the blend. Ozone cracking is measured by the failure time of a tapered specimen under a fixed load in a high severity ozone oven, whereas flex cracking is ranked by the De Mattia cut growth. The ozone resistance of BIMSM/BR/NR blends is compared to that of a BR/NR blend (with or without antiozonant) at constant strain energy densities. The effects of the BIMSM content in the blend, the structural variations of BIMSM, and the network chain length between crosslinks on these two failure properties, which are important in crosslinked compounds for applications in tire sidewalls, are discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2183,2196, 2007 [source] Pretreatment of barley husk for bioethanol productionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2005Beatriz Palmarola-Adrados Abstract This paper reports on the optimization of steam pretreatment of barley husk for high pentose and hexose recovery in the subsequent enzymatic hydrolysis step, as well as high ethanol yield, following simultaneous saccharification and fermentation. The parameters optimized in the steam pretreatment step were residence time (5,15 min), temperature (190,215 °C), and concentration of the acid catalyst (0 or 0.5% H2SO4). A microwave oven was employed for screening of the optimal conditions to obtain the highest sugar yield following combined pretreatment and enzymatic hydrolysis. The final optimization of the pretreatment prior to enzymatic hydrolysis was performed on a larger scale, in a steam pretreatment unit. Simultaneous saccharification and fermentation was carried out following steam pretreatment on 5 and 10% dry matter steam-pretreated slurries. Fermentability tests were performed to determine the effect of by-products (ie furfural and 5-hydroxymethyl furfural) in the bioconversion of glucose to ethanol by baker's yeast. The maximum glucose yield, 88% of the theoretical, was obtained following steam pretreatment with 0.5% H2SO4 at 200 °C for 10 min. Under these conditions, a sugar to ethanol conversion of 81% was attained in simultaneous saccharification and fermentation. Copyright © 2004 Society of Chemical Industry [source] Review Article: Fragrance technology for the dermatologist , a review and practical applicationJOURNAL OF COSMETIC DERMATOLOGY, Issue 3 2010Claudia S Cortez-Pereira MSc Summary Cosmetic product development has increased in recent years. The value of a product is emphasized in its safety and effectiveness. The stability study in the context of product quality evaluation during shelf life becomes primordial to guarantee the integrity of the physical, chemical, and olfactory properties. In this study, aromatic compositions had been submitted to the stability normal test, at low temperature (4.0 ± 2.0 °C), at room temperature (22.0 ± 2.0 °C), and in oven (45.0 ± 2.0 °C). The compositions were analyzed at 15, 30, 60, and 90 days versus a fresh aromatic composition 48 h after preparation, in which the organoleptic characteristics and pH value were evaluated besides undertaking sensory evaluation. The results demonstrated that at the high temperature (45.0 ± 2.0 °C), in which the oxidative processes of the fragrance components are accelerated, the cosmetic preparation "A" was chosen because it showed more acceptable physical,chemical properties and in terms of sensory evaluation of perfume character and intensity was approved for commercial use. [source] DRYING OF CHILI PEPPER (CAPSCIUM FRUTSCENS)JOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2010T.Y. TUNDE-AKINTUNDE ABSTRACT Drying is one of the common methods of food preservation and is carried out on untreated/unblanched and treated/blanched chili pepper using sun, solar and hot-air drying. The drying curves generated from the three methods showed that drying of treated/blanched pepper was faster than that of untreated/unblanched pepper. The drying rate period observed for all the methods and samples was the falling rate drying regime. This suggests that the blanching pretreatment assisted water loss and thus decreased the resistance to water loss at the surface of the product. The drying time of the dried pepper varied from 27 h for hot-air drying to 144.5 h for sun drying respectively. The values of moisture diffusivity coefficient ranged from 2.163 × 10,9 m2/s for hot-air drying to 1.125 × 10,9 m2/s for sun drying. PRACTICAL APPLICATIONS A common method of preserving pepper, a vegetable with versatile use, is drying and this is done by sun, solar and oven-drying methods. Climatic variations of sun and solar drying make it unsuitable for large-scale production. Hot-air drying is thus considered as an alternative drying method because it decreases drying time and improves the hygienic quality of the dried product. Pretreating pepper by blanching increases its rate of drying. The effect of each drying method on the drying rate, equilibrium moisture content and moisture diffusivity coefficient were used to compare the drying methods. Hot-air drying had the lowest drying time whereas pretreated samples also dried faster. The effective moisture diffusivity of oven dried samples as well as pretreated samples were highest. This indicates that oven drying reduces drying time and can be used to dry pepper samples for large-scale production. [source] COMPUTER-CONTROLLED MICROWAVE HEATING TO IN-PACKAGE PASTEURIZE BEEF FRANKFURTERS FOR ELIMINATION OF LISTERIA MONOCYTOGENES,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2005LIHAN HUANG ABSTRACT The objective of this study was to develop an in-package pasteurization technology to kill Listeria monocytogenes in ready-to-eat meats using microwave heating. This technology utilized an infrared sensor to monitor the surface temperature of beef frankfurters during microwave heating. The aim was to increase the surface temperature of frankfurters to a set point lethal to L. monocytogenes. A feedback control mechanism was used to control the power to the microwave oven. Results indicated that the simple on-off control mechanism was able to maintain the surface temperature of beef frankfurters near the respective set points of 75, 80 or 85C used in this study. This pasteurization process was able to achieve a 7-log reduction of L. monocytogenes in inoculated beef frankfurters using a 600-W nominally rated microwave oven within 12,15 min. If optimized, this system may provide the food industry with a terminal, postlethality pasteurization technology to kill L. monocytogenes in ready-to-eat meats within the final packages. [source] DEVELOPMENT and EVALUATION of MICROWAVE HEATING of APPLE MASH AS A PRETREATMENT to PRESSINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2004J.S. ROBERTS ABSTRACT Fuji, McIntosh, and Red Delicious apple mashes were heated in a 2450 MHz oven to achieve bulk temperatures of 40, 50, 60, and 70C. Three kilograms of mash at a depth of 0.016 m heated using 1500 W were the optimum parameters to heat apple mash in the microwave. Variety of the apple mash was shown not to have a significant effect on the heating performance. Comparing actual bulk temperature to the predicted bulk temperatures of 40, 50, 60, and 70C showed reproducibility of heating these mashes using microwave energy. Average variation between actual and predicted bulk temperatures were 1.48C for the Fuji mash, 0.98C for the McIntosh mash, and 1.13C for the Red Delicious mash. In addition, regional heating was investigated and four distinct regions of heating were observed: the corner, the edge, the middle, and the center. Color and moisture content of the mash were also measured and compared to unheated mash at 21C. [source] HEAT TRANSFER COEFFICIENT FOR COOKIE SHAPED OBJECTS IN A HOT AIR JET IMPINGEMENT OVENJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2001N. NITIN ABSTRACT Correlations for average heat transfer coefficient for cookie shaped objects in a hot air jet impingement oven were obtained using aluminum cookie models. The study was carried out in a pilot plant scale hot air jet impingement oven. The effects of individual cookie position, presence of surrounding cookies, air velocity, air temperature and rotation of the oven plate on average surface heat transfer coefficient were investigated. The value of the heat transfer coefficient ranged between 100,225 W/m2K and was found to be a strong function of jet air velocity. The impact of surrounding cookies on the heat transfer coefficient was more for smaller cookies, which had larger cookie-to-cookie spacing. [source] EFFECTS OF COOKING AND DRYING PROCESSES ON PHYSICAL, CHEMICAL AND SENSORY PROPERTIES OF LEGUME BASED BULGURJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2009NERMIN BILGIÇLI ABSTRACT The changes in physical, chemical and sensory properties of common bean (CB) and chickpea (CP) bulgur prepared with different cooking (atmospheric, pressure and microwave) and drying (oven at 60, 70 and 80C; microwave at 350 and 700 W) processes were investigated. Neither the cooking methods nor the drying methods significantly affected the ash and protein contents of CB and CP bulgur. Pressure cooking gave lower phytate phosphorus and higher bulgur yield and volume increase values when compared to the other cooking methods. Average bulgur yields were found as 82% for CB and 84% for CP. Cooking processes decreased the phytic acid content of the bulgurs between 25.2 and 39.5% according to raw legume. Ca, K, Mg, P, Zn, Cu and Fe contents of the bulgurs decreased in variable degrees (8.69,28.5%) when compared to raw materials. Pressure cooked and oven (80C) dried bulgur samples in the case of bulgur pilaf were appreciated by the panelists in terms of overall acceptability. PRACTICAL APPLICATIONS Bulgur is a valuable cereal product with its high nutritional value and long shelf life. In this research, bulgur process was applied successfully on common bean and chickpea, and new legume-based bulgur products improved. The bulgur yield (BY) of the legumes was above 80%. Pressure cooking increased the nutritional, sensory and technological quality of the legume bulgurs. [source] A SURVEY OF THE QUALITY OF SIX RETAIL BRANDS OF BONELESS, SKINLESS CHICKEN BREAST FILLETS OBTAINED FROM RETAIL SUPERMARKETS IN THE ATHENS, GEORGIA AREA,JOURNAL OF FOOD QUALITY, Issue 6 2007HONG ZHUANG ABSTRACT To assess the variation in quality of chicken breast fillets available from retail supermarkets, six brands of boneless, skinless fillets without additives were obtained from the fresh counter at grocery stores in Athens, GA, and the surrounding area during fall of 2005. The samples were stored at ,20C and subsequently cooked using a Henny Penny MCS-6 combi oven (Henny Penny Corp., Eaton, OH). Quality parameters of the fillets were measured on the cooked chicken breast fillets including cook yield, descriptive sensory flavor and texture profiling, and Warner,Bratzler (WB) shear force. Our results show that the average cook yield ranged from 78.1 to 80.9%, the average intensity of individual descriptive sensory characteristics was less than 5.4 in a 0,15 universal scale, and WB shear force values were less than 5.2 kg. There were no significant differences in the intensity among brands of all flavor attributes and the texture characteristics associated with moisture. However, significant differences were found among the brands for cook yield, mechanical properties of texture (including springiness, cohesiveness, hardness and chewiness) and WB shear force values. The variation of WB shear force measurements (coefficient of variation) depended on brand. These results indicate that differences exist in the quality and shear force consistency among market brands of boneless, skinless chicken breast fillets available in Athens, GA, and the surrounding area. PRACTICAL APPLICATIONS This study is the first survey reported to evaluate the quality of boneless, skinless chicken breast products without additives in U.S. retail market. This study supplies the evidence that the intensity of sensory quality is mild of cooked boneless, skinless chicken breast products and there are the differences in the quality among the different retail brands obtained by consumers. [source] Magnetic Resonance Temperature Mapping of Microwave-Fried Chicken FingersJOURNAL OF FOOD SCIENCE, Issue 5 2009Isil Barutcu ABSTRACT:, The main objective of this study was to compare the heating patterns of chicken fingers deep-fried conventionally and using a microwave. Two dimensional internal temperature maps of fried chicken fingers with rectangular geometry were measured post frying using magnetic resonance imaging (MRI). Frying was performed in a microwave oven at 365 W power level for 0.5 and 1.5 min after bringing the oil temperature to 180 ± 1 °C. Samples were also fried in a conventional fryer at 180 °C for 2 and 5 min for comparison. Variations in internal temperature distribution increased proportionally to frying time in both microwave and conventional frying. Internal thermal equilibrium is reached in all samples after 13 min of holding time. Internal structural changes, void formation, were also visualized in the images. Void formation did not significantly impact cooling rates. [source] Effects of Mild Heat Treatment on Microbial Growth and Product Quality of Packaged Fresh-Cut Table GrapesJOURNAL OF FOOD SCIENCE, Issue 8 2007L. Kou ABSTRACT:, The changes in packaged fresh-cut grape quality and microbial growth as affected by mild heat treatments and the retention of grape cap stems during 5 °C storage were evaluated. Each individual grape was either manually pulled off (stemless) from the stems, or cut (cut stem) to allow for a 1- to 2-mm cap stem remaining on the berry. The samples were sanitized in 100 mg/L chlorine solution for 1 min, followed by a mild heat treatment in a water bath (45 °C, 8 min) or an oven (55 °C, 5 min). After cooling, the berries were packaged in rigid trays sealed with a gas permeable film and stored at 5 °C. Product quality and decay rate were evaluated periodically during storage. The results indicate that in the package headspace for hot water treatment of stemless grapes, partial pressures of O2 declined significantly (P < 0.05) less and C2H4 increased significantly (P < 0.001) less than for the control and hot air treatment. Stem removal and heat treatment had significant (P < 0.05) effects on the decay rate of grapes during storage. Hot water treatment maintained a significantly lower decay rate than the control and hot air treatment throughout the entire storage. Color and texture were not significantly (P > 0.05) affected by either heat treatment or stem removal. Grapes that retained the cap stems and received hot water treatment had the lowest decay rate and lowest microbial growth with the absence of any negative impact on grape color, texture, and flavor. [source] Modeling Cooking Time to Inactivate Salmonella in Chicken Leg Quarters Cooked in an Air,Steam Impingement OvenJOURNAL OF FOOD SCIENCE, Issue 5 2006Tareq M. Osaili ABSTRACT:, Inadequate cooking of poultry products may lead to human foodborne infections. The use of mathematical models that describe heat transfer during cooking of chicken leg quarters may help in developing safer food products and minimizing time for cooking. The objective of this study was to develop regression models that predict cooking time required to reach internal temperatures of 71.1, 73.9, 76.7, and 82.2 °C in chicken leg quarters. Samples that had different weights, thicknesses, and initial internal temperatures were cooked in an air,steam impingement oven at temperature of 232.2 °C, humidity of 60%, and air velocity of 1.4 m/min. A thermocouple probe (type K) connected with a data acquisition system was inserted into the coldest point of each chicken leg quarter. Samples were cooked until they reached an internal temperature higher than 82.2 °C. The collected data of each sample in the data acquisition system were used to develop regression models that depend on sample weight, thickness, and initial temperature in predicting cooking times. Sample weight, thickness, and initial internal temperature had significant effects on the cooking time. The results of these models would be helpful for ready-to-eat poultry processors to meet lethality performance standards, and ensuring the safety and quality of skin on, bone in chicken leg quarters cooked via air,steam impingement ovens. 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