bluuebunny/crossref_metadata_2025_split huggingface dataset:
A NEW TECHNIQUE FOR EVALUATING FLUID‐TO‐PARTICLE HEAT TRANSFER COEFFICIENTS UNDER TUBE‐FLOW CONDITIONS INVOLVING PARTICLE OSCILLATORY MOTION
Authors: ZAREIFARD M.R. , RAMASWAMY H.S. 
Published: February 2007

ABSTRACT One of the critical parameters for the modelling of particle temperature profiles in continuous processing of particulate foods in a carrier liquid is the fluid‐to‐particle heat transfer coefficient between the fluid and the particles (hfp). A laboratory scale apparatus was fabricated to evaluate hfp under conditions imparting particle oscillatory motion while being heated in a model holding tube. Spherical particles (d = 12.7 × 10−3m) with centrally located fine‐wire flexible thermocouples (d = 7.62 × 10−5 m) were suspended from the upper mid‐section of a curved glass tube (ID = 50.8 × 10−3 m) to provide lateral movement of the particle as the tube was subjected to an oscillatory motion. A variable speed reversible motor, in conjunction with an electronic circuit board, was used to control the frequency and amplitude of the tube thereby keeping the particle in continuous motion. Time‐temperature data were gathered continuously from the time the particle‐mounted oscillatory unit, set at room temperature for the desired amplitude and frequency, was transferred to a heated sucrose solution (0, 30 and 50% w/w) at 70 or 90C. The hfp values were calculated from the evaluated heat rate index, fh, at three particle velocities (0.09, 0.16 and 0.26 m/s) under three oscillatory amplitudes (90, 180 and 270°). The hfp values increased with amplitude of oscillation and particle velocity, and decreased with the sucrose concentration. The hfp values associated with the fixed particles were higher than those for particles which were free to move.
MEASUREMENT AND PREDICTION OF THE PRESSURE DROP INSIDE A PIPE: THE CASE OF A MODEL FOOD SUSPENSION WITH A NEWTONIAN PHASE
Authors: MARTÍNEZ‐PADILLA L.P. , ARZATE‐LÓPEZ A.C. , DELGADO‐REYES V.A. , BARBOSA‐CÁNOVAS G.V. 
Published: February 2007

ABSTRACTThe aim of this study was to measure the pressure drops of a solid‐liquid food model and to compare pressure drop estimations obtained from proposed correlations for asymmetric distributed suspensions in a horizontal pipe. The model food suspension consisted of alginate spheres suspended in a Newtonian sugar syrup of medium viscosity. The suspension was pumped into a horizontal pipe and measurements for three different sphere diameters and solid‐phase concentrations were carried out. Particle velocity, necessary for pressure drop estimations, was predicted using the Eulerian approach, which assumed solid and liquid phases as continuous. Considerations taken were: one dimensional flow of fluid and particles, drag force acting on the particles and constant pressure drop. The momentum equations were solved by the fourth order Runge‐Kutta method. Predicted particle velocities showed a retarded parabolic profile compared to the fluid. Drag expressions used, considerably influenced the predicted particle velocities. Estimated pressure drops for the suspensions using the predicted particle velocities agreed with the experimental pressure drops when the tube‐particle diameter ratio was higher than 5.8.
SOLAR ABSORPTIVITY OF PEELED CASSAVA ROOT, YAM TUBER AND UNRIPE PLANTAIN FRUIT
Authors: NJIE DIVINE N. , RUMSEY THOMAS R. 
Published: February 2007

ABSTRACT Absorptivity is a property which governs the quantity of solar radiation absorbed by materials undergoing sun drying. A laboratory spectrophotometer was used to measure the spectral absorptivity of peeled cassava root, yam tuber, and unripe plantain fruit for wavelengths in the range 0.4–2.4 μm; 88% of solar radiation reaching the earth lies in this part of the electromagnetic spectrum. The total (i.e., integral) absorptivity calculated from the measured spectral absorptivity was 0.32 for fresh cassava which had a wet basis moisture content (M.C.) of 65%, 0.26 for fresh plantain (M.C. =61%) and 0.53 for fresh yam (M.C.=68%). Corresponding values for dried crops were 0.23 for cassava (M.C.=5%), 0.58 for plantain (M.C.=20%) and 0.77 for yam (M.C.=9%). Application of absorptivity data in evaluating heat transfer during sun drying of crops was discussed.
NEURAL NETWORK WITH PRINCIPAL COMPONENT ANALYSIS FOR POULTRY CARCASS CLASSIFICATION
Authors: CHEN Y.R. , NGUYEN M. , PARK B. 
Published: February 2007

ABSTRACTThis paper reports the results of applying principal component analyses (PCA) of spectral reflectance data to reduce the number of input nodes for neural networks for classification of wholesome and unwholesome poultry carcasses. The results showed that the models with PCA pretreatment of input data performed better than those models without pretreatment. When sensing moving poultry carcasses in an environment without room light with a visible/near‐infrared spectrophotometer, the neural network classification models with PCA pretreatment achieved 100% accuracies for training, validating, and testing. For carcasses moving at 60 birds/min, 50 factors were required for perfect classification, while for 90 birds/min 30 factors were required. When sensing in room light, the best model was generated with 30 factors for a shackle speed of 60 birds/min, with a test set accuracy of 95.8%. For 90 birds/min, the best model with a test set accuracy of 96.8% was obtained when 15 factors were used. This study showed that PCA reduced the number of input nodes to the neural network classifiers and, in most cases, improved the model's classification accuracy. It also required fewer training samples and reduced training time.
DRYING RATE EFFECT ON THE PROPERTIES OF WHEY PROTEIN FILMS
Authors: ALCANTARA C.R. , RUMSEY T.R. , KROCHTA J.M. 
Published: February 2007

ABSTRACT The effects of drying temperature, drying relative humidity and film thickness on the drying characteristics, water vapor permeability, and tensile properties of glycerol (Gly)‐plasticized whey protein isolate (WPI) films were investigated. 50%WPI:50%Gly and 60%WPI:40%Gly (dry basis) films were studied. Constant rate periods were compared among films. A higher temperature (95C) and lower relative humidity (30%RH) increased the slope of the weight versus time plot during the constant rate period, indicating shorter drying times to reach the falling rate period. Water vapor permeabilities were significantly lower for films dried at 95C and 30%RH than for films dried at 21C and 50%RH. Films dried at 95C and 30%RH were generally thinner, stiffer, stronger, and less extendable than films dried at 21C and 50%RH.
FLOW PROFILES OF POWER LAW FLUIDS IN SCRAPED SURFACE HEAT EXCHANGER GEOMETRY USING MRI
Authors: WANG WEI , WALTON JEFFREY H. , McCARTHY KATHRYN L. 
Published: February 2007

ABSTRACTScraped surface heat exchangers (SSHE) are prevalent in the food industry to heat/cool viscous fluids and to provide enhanced mixing. This work focused on developing and verifying a theoretical model to characterize the flow patterns in two‐dimensional angular flow in an SSHE geometry under isothermal conditions. Experimentally, the model was verified by a noninvasive magnetic resonance imaging (MRI) technique. Good agreement was achieved between the theoretical model and experimental data for a polyalkylene glycol, which behaved as a Newtonian fluid (n = 1), and a 1% CMC solution, a power law fluid with n = 0.77. However, the experimental flow profile tomato puree was characterized by apparent wall slip. The best fit, with respect to the power law model, was a flow behavior index of 0.11. This study provides the framework to quantify the effects of heat transfer on flow profiles in this geometry and the effectiveness of mixing.
THERMAL DESIGN PROCESS FOR ACIDIFIED CANNED PAPAYA (Carica papaya L.) PULP
Authors: MAGALHÄES M.M. DOS A. , TOSELLO R.M. , MASSAGUER P.R. 
Published: February 2007

ABSTRACT Previous results showed that the heat resistant portion of pectinesterase in the acidified papaya pulp var. “formosa” presented greater thermal resistance than Cl. pasteurianum. Based on this, and determined F7.8C77C, a value of 12.3 min was calculated using the heat resistant portion of pectinesterase as the target for the process, and applying 1.7 decimal reduction of the activity of the heat resistant enzyme (98% inactivation). Using Shiga (1976) an empirical relationship and a heating time of 12.9 min in water bath at 97C was established for the process. Three processing tests were carried out under these conditions using 6 cans per test. The processing values varied from 12.33 to 12.75 min at 77C. Statistical analysis showed no significant difference between tests and among cans as well as test at the 0.05 and 0.01 α level. After processing the cans, gelatinization, activity of remaining enzyme and micro‐organism growth were not detected. This shows that the process was able to inactivate the heat resistant portion of pectinesterase and kill the natural micro‐flora present on the pulp. By considering the initial variation of the pectinesterase activity in the pulp and F7.8C77C ‐ value of 16.7 min, a safety factor for the process was applied. This process was equivalent to 15 min of heating in water bath at 97C and corresponded to 2.3 decimal reductions in activity of heat resistant pectinesterase. An inoculation pack study was performed to verify the microbiological safety of such process. Each can of papaya pulp was inoculated with 1 mL of a 104 spore/mL suspension of Cl. pasteurianum. Swelling of the cans, growth after subculturing and pectinesterase were not detected after incubation, showing that the pulp could be safely processed. The storage test showed no significant changes in the color, flavor, aroma and texture of the canned acidified papaya pulp.
SUPERPOSITION OF COMPLEX VISCOSITY CURVES DURING GELATINIZATION OF STARCH DISPERSION AND DOUGH
Authors: LIAO H‐J. , TATTIYAKUL J. , RAO M.A. 
Published: February 2007

ABSTRACTComplex viscosity (η*) of 8% tapioca starch dispersion (STD) during gelatinization at a specific oscillatory frequency (ω, rad s−1) was independent of the heating rates: 1.5 to 6.0C min−1 when plotted against temperature as the independent variable instead of time. The influence of ω in the range: 3.14 to 62.83 rad s−1 on η* was scaled by a frequency shift factor resulting in a reduced complex viscosity (η*R) versus temperature (58–88C) master curve. Similar η*R versus temperature master curves were derived for η* data on a 8% waxy rice STD at the heating rate 2C min−1 and ω values 1.27 to 125.6 rad s−1, and a 45.5% waxy rice dough at the heating rate 4C min−1 and ω values 1.27 to 94.2 rad s−1. The areas under the η*, at ω=6.28 rad s−1, versus temperature curves of the tapioca and the waxy rice STDs with different starch concentrations were exponentially related to the concentrations.
SPECIFIC HEAT OF SOYBEAN
Authors: DESHPANDE S. D. , BAL SATISH 
Published: February 2007

ABSTRACTThe specific heat of soybean, determined by the method of mixtures, exhibited linear positive correlation with moisture content in the moisture range from 8.1 to 25% d.b. for the mean temperature of 315 K and can be expressed in the form as Cp=1.444 (1 + 4.06 × 10−2M). The specific heat values increased from 1.926 to 2.912 kj/kg‐K in the given moisture range. Further, the specific heat values obtained in the present study when compared with the values predicted by the other empirical methods indicated the close approximation of observed and estimated values.
THIN‐LAYER DRYING OF DATES
Authors: HASSAN BAKRI H. , HOBANI ALI I. 
Published: February 2007

ABSTRACTThin‐layer drying rates of two date cultivars, namely, Sukkari and Sakie were experimentally determined at three drying temperatures 70, 80, and 90C. Three drying models were evaluated for the thin‐layer date data. These were the exponential model, Page equation, and the approximation of diffusion model. The Page equation fitted the data best. Two empirical expressions of Page equation for predicting moisture ratio as a function of drying time and drying temperature for the two date cultivars are presented.
REUSE OF SUCROSE SYRUP IN PILOT‐SCALE OSMOTIC DEHYDRATION OF APPLE CUBES
Authors: VALDEZ‐FRAGOSO A. , MUJICA‐PAZ H. , GIROUX F. , WELTI‐CHANES J. 
Published: February 2007

ABSTRACTOsmotic dehydration (OD) treatments of apple cubes were carried out in a pilot plant, which consisted of an OD vessel, a filter, a vacuum evaporator, and recirculating pumps. The osmotic solution (OS) was maintained at 59.5 ± 1.5 °Brix and 50C by reconcentration in the evaporator, and suspended particles were eliminated by filtration. OS was reused to process 20 batches of apple cubes, maintaining a constant OS/fruit ratio of 5/1 (w/w) by addition of new OS. Evolution of pH, titratable acidity, soluble solids, water activity, color, reducing sugars, and microbial load in the OS was evaluated along the OD process. The OD parameters and the apple color were determined. Values of the physicochemical properties of the OS stabilized after 10 treated batches. A microbial load of 2590 ± 330 CFU/mL was observed in the OS at the end of 20 OD treatments. Water loss, solids gain and color of dehydrated apple cubesobtained in OD process with reuse of the OS were similar to those found in an OD process carried out with a nonrewed OS.
OIL POINT PRESSURE OF SOYBEAN
Authors: AJIBOLA O.O. , OKUNADE D.A. , OWOLARAFE O.K. 
Published: February 2007

ABSTRACTThe effects of processing conditions such as preheating moisture content (6, 8.3, 10 and 12%‐wet basis), heating temperature (70, 85, 100 and 115C) and heating time (15, 20, 25 and 30 min) on the oil point pressure of soybean seed was investigated. It was observed that increase in preheating moisture content from 6.0% to 12.0% (wet basis) increases the oil point pressure. The oil point pressure was found to decrease with increase in temperature and heating time from 70C to 115Cand 15 min to 30 min, respectively. It was also observed that increase in the moisture content during expression (postheating moisture content) from 2.6 to 11.6% increases the oil point pressure and the relationship can adequately be represented by a linear model. The postheating moisture content is affected by the initial moisture content, the heating temperature and heating time; therefore these factors affect the oil point pressure. The oil point pressure values obtained in the study were between 10.4 MPa (for sample at a moisture content of 6.0% heated at 115Cfor 30 min) and 17.2 MPa (for sample at a moisture content of 12.0% heated at 70C for 15 min).
THERMO‐PHYSICAL PROPERTIES OF SELECTED VEGETABLES AS INFLUENCED BY TEMPERATURE AND MOISTURE CONTENT
Authors: ALI S.D. , RAMASWAMY H.S. , AWUAH G.B. 
Published: February 2007

ABSTRACTThermo‐physical properties of selected vegetables (cassava, eggplant, ginger, green pepper, white radish and zucchini) were evaluated under different conditions of temperature (5 to 40C) and moisture content (30 to 94% wb). Test samples were equilibrated to a given temperature and moisture content prior to use. The thermal conductivity and heat capacity were measured using the line heat source probe and the differential scanning calorimeter, respectively. Depending on the state, temperature, moisture content and the type of vegetable, average heat capacity varied from 1.5 to 4 kJ/kgC, while the thermal conductivity varied from 0.08 to 0.60 W/mC. Heat capacity of the unfrozen vegetables was found to be approximately twice as much as values obtained for the frozen ones. Although both temperature and moisture affected the thermal conductivity, the latter had the greater influence. Generally, differences in measured data and responses to both temperature and moisture content were attributed to differences in structural characteristics and composition. Correlations were developed for estimating thermo‐physical properties of several vegetables.
LOW ORDER DYNAMIC MODEL of A VAPOR COMPRESSION CYCLE FOR PROCESS CONTROL DESIGN
Authors: LEDUCQ D. , GUILPART J. , TRYSTRAM G. 
Published: February 2007

ABSTRACTControl of food processes involving vapor compression cycles as actuators is often a difficult task: indeed this particular device is itself a complex process including coupled unit operations as evaporation, compression, condensation and expansion. Nevertheless, an accurate control of heat transfer rate is often essential for global quality of product and stability of flow in exchangers.Moreover a number of vapor compression systems are already equipped with variable speed‐compressors and fans. However, due to lack of knowledge about the dynamic behavior of these systems, the industry has not taken full advantage of these variable devices to get substantial control performance improvement.This paper presents a lumped‐parameter model for describing the dynamics of vapor compression cycles. Based on moving‐boundary approach for the description of two‐phase/single phase interface inside the heat exchangers, this low‐order model composed of only ordinary differential equations can be highly useful for design of control strategies. This model has been validated on an experimental device and a good agreement between measurements and computed data has been found. Use of this model in food process control design is discussed.
DIELECTRIC PROPERTIES of STARCH SOLUTIONS AS INFLUENCED BY TEMPERATURE, CONCENTRATION, FREQUENCY and SALT
Authors: PIYASENA P. , RAMASWAMY H.S. , AWUAH G.B. , DEFELICE C. 
Published: February 2007

ABSTRACTDielectric properties of starch solutions (1 to 4% w/w) were evaluated at temperatures ranging from 20 to 80C at 10, 20 and 30 MHz. the effect of added salt (0.2 and 0.5% w/w) was investigated in relation to changes in trends exhibited by the relative permittivity, loss factor and penetration depth. the relative permittivity ranged from 46 to 308 and 65 to 92 for solutions with and without salt, respectively. the corresponding loss factor ranged 266 to 4133 and 9 to 266, respectively. Temperature, frequency, concentration and their interactions had different levels of significance on the dielectric properties of starch solutions. Salt enhanced the relative permittivity, and its effect conformed to the anomalous dispersion phenomenon. the loss factor increased with increasing temperature and salt content, and penetration depths associated with salt‐enriched samples were low compared to samples without salt. Generally, the effects of temperature, frequency, concentration and salt on the dielectric properties of starch solutions were attributed to the complex interaction between conductivity, density, moisture content, loss angle and starch rheological properties. Excellent correlations were developed that could be used for estimating the dielectric properties of starch solutions with and without salt.
COMPARISON OF IN‐LINE CONSISTENCY MEASUREMENT OF TOMATO CONCENTRATES USING ULTRASONICS AND CAPILLARY METHODS
Authors: DOGAN NIHAN , McCARTHY MICHAEL J. , POWELL ROBERT L. 
Published: February 2007

ABSTRACTThis study focuses on the development of a noninvasive, in‐line rheometer using ultrasonics and its comparison with data from a traditional capillary viscometer. The ultrasonic based pointwise viscosity measurement technique combines a measurement of the velocity profile and the pressure drop to determine the shear rate and the shear stress distributions, respectively in a pipe. The experiments were carried out using tomato concentrates at 8.75%, 12.75%, and 17.10% total solids content. The flow system consisted of a 53.2 mm diameter acrylic tube, a positive displacement pump and two pressure transducers. Multiple shear viscosity‐shear rate data were recorded under actual pipeline conditions from a single combined measurement of the velocity profiles using ultrasonics and the pressure gradient, using the pressure transducers. The samples showed shear thinning behavior and a yield stress. Power law and Casson models were used to fit the data and both obtained R2 values higher than 0.99. The yield stress was also directly determined from the velocity profiles. Shear viscosity versus shear rate data of the 12.75% total solids sample were obtained by capillary rheometry at four different flow rates. These showed very‐good agreement with those obtained using the velocity profile technique.
SUPERCRITICAL FLUID EXTRACTION of QUERCETIN FROM ONION SKINS
Authors: MARTINO KARINA GOROSTIAGA , GUYER DANIEL 
Published: February 2007

ABSTRACTSupercritical fluid extraction, with ethanol‐modified carbon dioxide, of free quercetin from onion skins (red and yellow varieties) was studied. Static mode was investigated as an extraction method, which generated a total of 0.024 g of free quercetin per kg of onion skin for the red variety, and 0.020 g per kg for the yellow variety, at 5700 psi, 40C, an average of 7.6% (molar concentration) of ethanol, and in an extraction period of 2.5 h.The modifier was found to have an important influence on free quercetin recovery. the greater the amount of ethanol collected in the trap, the greater the amount of free quercetin recovered.Identification and quantification analysis were conducted in a High Performance Liquid Chromatography system.
WATER ABSORPTION, LEACHING and COLOR CHANGES DURING the SOAKING FOR PRODUCTION of SOY‐BULGUR
Authors: BAYRAM MUSTAFA , KAYA AHMET , ÖNER MEHMET DURDU 
Published: February 2007

ABSTRACTIn this study, the soaking process, which is the first step of soy‐bulgur production to develop a new type food product, was investigated. the soaking operation was conducted at 30, 50 and 70C for 120 min and samples were taken from the soybean and soaking water at 10 min intervals. Moisture content and color (L, a, b and YI values) of soybean were measured, as well as soluble solids content and color (L, a, b and YI values) of soaking water during the soaking process. the results were analyzed by using ANOVA and Duncan test.Soaking time and temperature were significantly effective (P < 0.05) on all variables, except the time effect on the YI‐value.During the soaking, moisture content, lightness (L) and yellowness (b) increased and, redness (a) and yellowness index (YI) of soybean decreased. Soluble solids content, yellowness and yellowness index increased in contrast to a decrease in the lightness and greenness of the soaking water.As a result, soluble solids content in the soaking water increased, which illustrated the leaching of soluble solids from soybean to water. Color of soybean turned to lights, in contrast to darkening and opaqueness of water during soaking. Results showed that the moisture content, soluble solid content, L, a, b and YI values can be successfully modeled using polynomial equations, which can be used to estimate their changes during the soaking operation.
OBSERVATIONS ON STRAWBERRY TEXTURE A THREE‐PRONGED APPROACH
Authors: SZCZESNIAK ALINA S. , SMITH BERTHA J. 
Published: February 2007

AbstractSensory, instrumental and microscopic methods of evaluation were combined to permit relating textural parameters to structural characteristics of fresh, frozen and rehydrated freeze‐dried strawberries. Large cells and thin cell walls appear to account for the ease of textural damage. Degradation of cell walls, cell rupture and plasmolysis caused by senescence or processing are responsible for softening, loss of crispness and easy juice release. A good agreement was obtained between the three methods of texture evaluation.
MEASUREMENT OF TOMATO FIRMNESS WITH A UNIVERSAL TESTING MACHINE
Authors: HOLT C. B. 
Published: February 2007

AbstractA technique of punch‐testing tomatoes to measure the firmness of the different anatomical parts has been developed. A plunger with a 0.040 inch diameter tip tapering to a 0.020 inch diameter shaft is attached to the crosshead of an Instron Universal Testing Machine and driven into the tomato at a speed of 1 cm/min. Distinct peaks are observed on the force‐displacement trace which are related to the firmness of the various parts of the structure. The method can be used to follow changes in firmness during ripening, to detect ripening abnormalities, to measure differences between varieties and to detect variations in firmness over the surface of individual tomatoes.