bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in human plasma melatonin profiles in response to 50 Hz magnetic field exposure
Authors: Wood A. W. , Armstrong S. M. , Sait Ml. , Devine L. , Martin M. J.
Published: February 2007

Abstract: The effects of power‐frequency magnetic fields on nighttime plasma melatonin were studied in a group of 30 adult male human subjects. Exposure consisted of 20 μT (200 mG) at 50 Hz (circularly polarized) at certain times in relation to the predicted time of onset of rise in melatonin concentration for a particular individual (the time of onset was predicted from a previous screening night). Response to this exposure was compared to sham‐exposure (in random order). When exposure preceded onset of rise, a significant delay in onset time relative to sham‐exposure of approximately half an hour was observed, with indications (marginally significant) of a reduction in maximum melatonin level. Analysis of distribution of time‐delays is consistent with two populations: those individuals who respond (around 20%) and those that do not. Magnetic fields generated by square‐wave currents produce more marked reductions in the maximum level when compared to sinusoidal waveforms, but there was no significant difference in onset time.
Interactions of melatonin with membrane models: Portioning of melatonin in AOT and lecithin reversed micelles
Authors: Ceraulo L. , Ferrugia M. , Tesoriere L. , Segreto S. , Livrea M. A. , Liveri V. Turco
Published: February 2007

Abstract: The interaction of melatonin with water containing either sodium bis (2‐ethylhexyl) sulfosuccinate (AOT) or soybean phosphatidylcholine (lecithin) reversed micelles has been investigated by UV absorption spectroscopy, at a molar ratio of melatonin: surfactant 1: 800 for AOT and 1: 400 for lecithin reversed micelles, and by varying the water:surfactant molar ratio (R). Our results suggest that in the presence of domains from apolar organic solvent to surfactant and to water, melatonin positions itself in the micellar phase, with a preferential location in the surfactant polar head group domain, independent of the nature of the surfactant and the amount of water encapsulated into the micellar core. Effects are due to the hydrophilic and lipophilic moieties of melatonin. The effectiveness of melatonin as an electron donor and free radical scavenger has been recently recognized. While supporting the hypothesis that melatonin may provide antioxidant protection without the benefit of receptors, present findings may suggest that the molecule could easily scavenge aqueous as well as lipophilic radicals.
The onset of increased melatonin secretion after the onset of darkness in sheep depends on the photoperiod
Authors: Ravault J. P. , Chesneau D.
Published: February 2007

Abstract: In sheep, melatonin secretion occurs rapidly after the onset of darkness, but the interval fluctuates according to different authors. The aim of this study was to determine this interval in sheep subjected to a long or a short photoperiod. Blood samples were taken at the right jugular vein every 100 s for 1 hr after the onset of darkness. The experiment was repeated on three consecutive days either in long (LD 16:8) or in short photoperiod (LD 8:16) on the same animals. Melatonin secretion was found to begin within 11 min under long photoperiod and 20 min under short period. It can be concluded that the onset of melatonin secretion depends on the duration of the photoperiod.
Changes in nocturnal pineal melatonin synthesis during the perimenopausal period: Relation to estrogen levels in female rats
Authors: Okatani Yuji , Morioka Nobuyuki , Hayashi Kazutoshi
Published: February 2007

Abstract: To evaluate changes in melatonin synthesis during the perimenopausal period in the female rat and to determine the effects of estrogen on melatonin synthesis, pineal levels of tryptophan, melatonin and norepinephrine and activities of N‐acetyltransferase (NAT) and hydroxyindole‐O‐methyltransferase (HIOMT) were determined. Homogenates for assay were prepared from the pineal glands of female virgin Sprague‐Dawley rats between 4 and 24 months of age in the middle of the dark period of a daily light/dark cycle. Serum 17 β‐estradiol (E2) concentrations were also determined. Pineal melatonin levels significantly decreased from month 4–12 and significantly increased from month 12–16, decreasing thereafter. Serum E2 concentrations significantly decreased from month 12–16, and remained low thereafter. No significant changes in tryptophan or norepinephrine were seen. NAT activities paralleled the time course of changes in melatonin. HIOMT activities decreased gradually from month 4–24. Subcutaneous implantation of an E2 capsule between months 12 and 16 resulted in significant decreases in levels of melatonin and NAT activity at month 16. Ovariectomy at month 4 or 12 led to significant increases in the levels of melatonin and NAT activity. These findings represent a temporal increase in pineal melatonin synthesis during the perimenopausal period, and suggest that the increase in melatonin synthesis activity at that time might result from decreasing levels of endogenous estrogen. The effect of estrogen on melatonin synthesis appeared to involve modulation of NAT activy.
Hematopoietic effect of melatonin involvement of type 1 K‐opioid receptor on bone marrow macrophages and interleukin‐1
Authors: Maestroni Georges J. M. , Zammaretti Francesca , Pedrinis Ennio
Published: February 2007

Abstract: Melatonin has immuno‐enhancing properties and exerts colony‐stimulating activity (CSA) via T‐helper cell‐derived opioids. Opioid agonists may mimic the CSA of melatonin with an order of potency that suggests the presence of a type 1 K‐opioid receptor (type I kOR [KI‐OR]). The kOR antagonist nor‐binaltorphimine neutralized the in vitro effect of melatonin and inhibited regeneration of hematopoiesis in mice treated with carboplatin. The CSA of dynorphin A was abolished by incubation of adherent cells with antisense (AS) oligodeoxynucleotide to kOR or by addition of anti‐interleukin (IL)‐I monoclonal antibody (mAb), which also neutralized the effect of melatonin. Bone marrow cells that express kORs were identified to be macrophages. In conclusion, we describe the presence of kORs in bone marrow macrophages and suggest a hematopoietic function for melatonin via endogenous K‐opioid agonists and, possibly, IL‐I.
Melatonin and its precursors scavenge nitric oxide
Authors: Noda Y. , Mori A. , Liburdy R. , Packer L.
Published: February 2007

Abstract:Nitric oxide (NO) scavenging activity of melatonin, N‐acetyl‐5‐hydroxytryptamine, serotonin, 5‐hydroxytryptophan and L‐tryptophan was examined by the Griess reaction using flow injection analysis. l‐Hydroxy‐2‐oxo‐3‐(N‐methyl‐3‐aminopropyl)‐3‐methyl‐1 ‐ triazene (NOC‐7) was used as NO generator. The Griess reagent stoichiometrically reacts with NO2, which was converted by a cadmium‐copper reduction column from the stable end products of NO oxidation. Except for tryptophan, all the compounds examined scavenged NO in a dose‐dependent manner. Melatonin, which has a methoxy group in the 5‐position and an acetyl side chain, exhibited the most potent scavenging activity among the compounds tested. Serotonin. N‐acetyl‐5 hydroxytryptamine, and 5‐hydroxytryptophan, respectively, showed moderate scavenging activity compared to melatonin. Tryptophan, which has neither a methoxy nor a hydroxyl group in the 5‐position, exhibited the least NO scavenging activity.
Tape‐stripping method in man: comparison of evaporimetric methods
Authors: Zhai Hongbo , Dika Emi , Goldovsky Marina , Maibach Howard I.
Published: February 2007

Background/purpose: If the occlusion time of a closed chamber evaporimeter on the skin is too long, saturation might occur. We previously compared an open chamber and a closed chamber device on healthy volunteers. Comparable data on stripped skin with higher evaporation rates are not available. This study compares the sensitivity and correlation of open and closed chamber devices in a tape‐stripping human model. The amount of tape removed SC was also quantified with a protein assay method.

Methods: Ten healthy volunteers (six male and four female; seven Caucasians and three Asian; mean age 38±16) were enrolled. In a randomized manner, one forearm was measured by an open chamber device and the opposite by a closed chamber device. After recording baseline measurements, 20 strippings were taken on each test site with tape disks. Transepidermal water loss (TEWL) was measured at the end of 10 and 20 tape strippings at each test site. Stratum corneum (SC) aggregates in the strips was assayed.

Results: The mean values obtained from two devices were similar after 10 trips and 20 strips. There was no statistically significant difference. The closed chamber device showed a slightly higher (but not significant) inter‐individual coefficient of variation. SC aggregates in the strips were similar and without a statistically significant difference.

Conclusion: The study suggests that both devices might yield similar TEWL values on stripped human skin in vivo.
Processing and Assembly of the Dystrophin Glycoprotein Complex
Authors: Allikian Michael J. , McNally Elizabeth M.
Published: February 2007

The assembly, processing and translocation of proteins occur constantly in all cells, and these processes also take place during the genesis, maintenance and repair of skeletal muscle. Skeletal muscle fibers are composed of myofibrils and are surrounded by a muscle plasma membrane, the sarcolemma. The sarcolemma serves as a docking location for many proteins. These proteins are important for establishing the physical connection between the extracellular matrix and the cytoskeleton and play a role in transmitting force related to muscle contraction. This physical connection is maintained through a myriad of proteins including the dystrophin glycoprotein complex (DGC). Normal sarcolemmal function requires proper DGC synthesis and positioning, and perturbation of the DGC leads to muscle membrane instability and disease.
Use of Enzymes for the Processing of Biomaterials
Authors: Unuma Hidero
Published: February 2007

Ceramic/polymer composites and hollow ceramic microspheres are receiving attention as biomaterials as a bone/tissue substitute and cancer remedy. This article describes the advantages of the use of enzymes as “controllable precipitant supplier” in the processing of such biomaterials. It has been demonstrated that hydroxyapatite (HA)/polymer composites and hollow microspheres of Y2O3, Fe3O4, and HA may be fabricated in a shorter time and using a simpler operation.
Direct Writing of Dielectric Ceramics and Base Metal Electrodes
Authors: Smay James E. , Nadkarni Sarosh S. , Xu Jian
Published: February 2007

Three‐dimensional structures were assembled by direct writing of colloidal gel‐based inks of electro‐ceramic and metal electrode compositions. The ternary mixtures of BaTiO3, BaZrO3, and SrTiO3 were explored via an active mixing nozzle print strategy that allowed for rapid screening of complex oxide ceramics. In a second experiment, Ni and BaTiO3 inks were developed from commercially available powders in the form of concentrated, aqueous colloidal gels having shear thinning with yield stress rheology. The different surface chemistry of Ni and BaTiO3 was accommodated by adsorbing a bi‐layer of oppositely charged polyelectrolytes on the BaTiO3 particles. Alternating layers of metal and ceramic were printed to build a multilayer structure. The multilayer Ni–BaTiO3 structures were sintered in a reducing atmosphere and the capacitance was measured. These two examples illustrate the use of discrete or graded deposition capabilities of direct writing.
PROCESSING WHEY‐TYPE BY‐PRODUCT LIQUIDS FROM COTTONSEED PROTEIN ISOLATION WITH ULTRAFILTRATION AND REVERSE OSMOSIS MEMBRANES
Authors: LAWHON J. T. , LIN S. H. C. , HENSLEY D. W. , CATER C. M. , MATTIL K. F.
Published: February 2007

Cottonseed wheys resulting from protein isolation from cottonseed flour were processed by semi‐permeable ultrafiltration (UF) and reverse osmosis (RO) membranes. The UF membrane fractionated the soluble whey constituents by retaining protein and passing through salts, carbohydrates and other non‐protein components along with most of the water. The UF membrane effluent was then processed through an RO membrane to recover a secondary product containing the whey materials not retained in the protein product from the UF membrane.

The feasibility of recycling effluent from the RO membrane for reuse in subsequent protein extractions was demonstrated. Thus, the threat of water pollution from effluent disposal could be eliminated completely and process water requirements drastically reduced.

Spray‐dried UF protein concentrates were tested for utilization in protein fortification of breads and noncarbonated beverages and as whipping products. They exhibited commercial potential for use in these food applications.

The economics of processing the whey‐type liquids by the membrane process under investigation were analyzed. Membrane processing of wheys by each of two alternative whey processing systems proved to be economically attractive.
EFFECT OF STORAGE AND PROCESSING CONDITIONS ON SORGHUM KERNEL STRENGTH
Authors: SUTER D. A. , RUPP R. A. , LANE G. T. , SULLINS R. D.
Published: February 2007

Compressive strength of sorghum kernels was measured to determine the effect of storage conditions on processing for animal feed. Ensiling grain affected a larger decrease in kernel compressive strength than did storage at a high moisture level. Results similar to the above were noted for tests conducted on kernels obtained from animal feces. Microscopic examination of kernels from each treatment revealed greater removal of kernel structure for those of lower compressive strength.
ENERGY CONSUMPTION FOR REFRIGERATED, CANNED, AND FROZEN PEAS
Authors: RAO M. A.
Published: February 2007

The energy inputs at different stages in the total food cycle of peas were estimated for the market modes: refrigerated, frozen, and canned. The energy accounting showed for refrigerated 3,368; for canned 3,637; and for frozen 3,281 Btu/2.8‐oz serving. Because the energy consumption for each market mode is of the same order of magnitude, there is little reason for the consumer to select on bases other than availability, taste preference, and convenience. It was also found that energy for packaging, marketing, shopping, and in the home can be high depending on the market mode. Measures to reduce energy consumption are discussed for several sectors.
PREDICTION OF FREEZING TIMES FOR FOODS AS INFLUENCED BY PRODUCT PROPERTIES
Authors: HSIEH R. C. , LEREW L. E. , HELDMAN D. R.
Published: February 2007

This investigation utilizes a computer simulation technique to predict the freezing times and temperature history curves for food products. The input information consists of the product properties for temperatures above the initial freezing point, freezing medium conditions and the initial product temperature.

It has been established that food products with lower initial freezing points, higher initial water contents and higher initial product densities will have longer freezing times. The prediction of freezing time is most sensitive to the accuracy of the measurement of the product density and the initial freezing point if the freezing point is above −0.5°C. The influence of the accuracy of unfrozen product thermal conductivity data on the freezing time is not important in the range of 0.45 to 0.55 W/m°K investigated. The combined influence of inaccuracy in measuring these product properties on the freezing time prediction will be significant even if the influence of an individual product property is small.
MASS TRANSFER CHARACTERISTICS OF HOLLOW FIBER ULTRAFILTRATION OF SOY PROTEIN SYSTEMS
Authors: CHERYAN MUNIR
Published: February 2007

Mass transfer characteristics and the applicability of theoretical transport models in ultrafilitration were evaluated in a pilot‐scale hollow fiber system processing soybean water extracts. Permeate flux was found to increase linearly with transmembrane pressure and then reach an asymptotic value. Substantial deviations from the pure water permeation line and marked hysteresis effects were also observed, indicative of concentration polarization and additional hydrodynamic resistance at the membrane surface. Pressure‐independence occurred at lower pressures with lower Reynolds Numbers (Re) and higher Schmidt Numbers (Sc). Flow rate and temperature significantly affected flux in the totally polarized region. The exponent in the flux‐Reα relationship varied from 0.6 at 20°C to 0.32 at 50°C. Theoretical laminar flow mass transfer models were found to predict Sherwood Numbers (Sh) and flux lower than experimental values. The correlation that fit the data best was Sh = 0.181 (Re).47 (Sc).33
SIMULATION OF AN IMMOBILIZED ENZYME PARTICLE USING β‐GALACTOSIDASE ADSORBED TO A PHENOL‐FORMALDEHYDE RESIN
Authors: GRULKE ERIC A. , OKOS MARTIN R. , SYVERSON ALDRICH
Published: February 2007

The mass transfer and kinetic properties of both soluble and immobilized β‐galactosidase were investigated. A reversible enzyme kinetic model was found to best fit the soluble and immobilized enzymatic lactose hydrolysis. A finite difference model was used to simulate the steady state and unsteady state behavior of an immobilized enzyme particle. The performance of the catalyst in a stirred tank reactor was simulated by using the physical properties of the support with the kinetic model and varying the effective substrate diffusivity to fit the data. A sensitivity analysis was performed to evaluate the effect of particle size, diffusivity, external mass transfer coefficient and enzyme loading.
THE HEAT OF COMBUSTION OF DRIED CITRUS PULP
Authors: KESTERSON J. W. , CRANDALL P. G. , BRADDOCK R. J.
Published: February 2007

The heat of combustion of dried citrus pulp has been found to be 4150 ± 118 cal/g or 7470 ± 212 Btu/lb. Dried citrus pulp has been compared with Bunker “c” fuel as a source of energy and found to be more valuable as a livestock feed.
KINETICS OF THERMAL INACTIVATION FOR A PECTIC ENZYME IN SWEET CHERRY BRINES1
Authors: ATHANOSOPOULOS P. E. , HELDMAN D. R.
Published: February 2007

The manufacturing of several sweet cherry products involves the use of calcium bisulfite brines and generates significant amounts of the brine for disposal. One of the primary concerns preventing the reclamation and reuse of these brines is the enzymatic softening of product caused by polygalacturonase enzymes that may be present in spent brine. The objective of this investigation was to evaluate the thermal stability of the polygalacturonase enzyme in cherry brine so that thermal inactivation processes can be designed.

The first‐order rate constants to describe thermal inactivation of polygalacturonase in cherry brine were measured over a range of typical pasteurization temperatures (68°to 72°C). The results were used to characterize thermal resistance of the enzyme in terms of Z‐value ( 8.4°C) and activation energy (271kJ/mole). The thermal stability of the enzyme was maximum between pH 2.8 and 3.5 and at sugar concentrations above 12%. A pasteurization system for cherry brine should be designed with all of the thermal stability characteristics considered in order to assure maximum product quality.
EFFECT OF EXTRUDER RETENTION TIME ON CAPILLARY FLOW OF SOY DOUGH1
Authors: JASBERG B. K. , MUSTAKAS G. C. , BAGLEY E. B.
Published: February 2007

Soy dough (defatted soy flakes), at 120° C and 30% moisture, was extruded through a series of dies of differing length (L) and radius (R). Rlots of pressure (P) were linear with the length to radius ratios (L/R) of the dies at constant output rate (Q) and R. The intercepts of the P versus (L/R) plots on the P = O axis give the end corrections (e) for capillary flow at each output rate. For soy dough, these end corrections were surprisingly large at low output rates and generally decreased rapidly with increasing output rate. This is contrary to the normal behavior of viscoelastic fluids, such as thermoplastics, where the end correction increases with increasing output rate. Both the end correction, which is a measure of the elastic properties of the soy dough, and the viscosity of the soy dough depended on the output rate as expected and also on the retention time of the material in the system.
MATHEMATICAL SIMULATION OF THE THERMAL BEHAVIOR OF FROZEN MEAT DURING ITS STORAGE AND DISTRIBUTION
Authors: ZARITZKY NOEMÍ E.
Published: February 2007

During the various stages of marketing, frozen food products are frequently subjected to changes in temperature which affect their quality.

In the present work, a mathematical model is developed to analyze the thermal behaviour of frozen meat subjected, under different insulation conditions, to thermal step functions and periodic fluctuations in temperature varying in amplitude and frequency.

The heat transfer equation has been numerically solved, since it is a system with physical properties that vary with the temperature, and fluctuating boundary conditions.

At the same time, laboratory experiments were performed to verify that the mathematical model is applicable to one‐dimensional and three‐dimensional heat transfer problems.

The obtained results were compared with analytical solutions for the heat transfer equation, with constant coefficients, determining the temperature range for which it is possible to use average values in the physical properties.
HYDROGEN IONS PROFILES, APPARENT MOBILITY, AND DISAPPEARANCE DURING COOKING OF MEAT EMULSION—1. SLAB GEOMETRY
Authors: MITTAL GAURI S. , BLAISEDELL JOHN L.
Published: February 2007

A simulation model was developed by considering diffusion, convection and first order chemical reaction to predict the hydrogen ion profiles during cooking of meat emulsion slab. The model was experimentally verified for various processing conditions and the compositions of the produci. There was a sharp increase of pH at the initial stage of thermal processing and it reached to a steady state value at the end of processing. The Eyring's Absolute Reaction Rate Theory described the H+ diffusivity and reaction rate constant reasonably well. The disappearance of H+ due to chemical reaction contributed the most in defining the H+ profiles during processing.
ANALYSIS OF KINETICS OF QUALITY CHANGE IN FROZEN FOODS1
Authors: LAI DAR‐JEN , HELDMAN DENNIS R.
Published: February 2007

Temperature fluctuations of frozen foods are of influence on frozen food quality. Prediction of quality changes under temperature fluctuations is therefore important in assuring high product quality and, by optimizing storage temperature, in conserving energy. This study is focused on applying kinetic models in analyzing Time‐Temperature‐Tolerance (TTT) data for frozen food storage and investigating the potential for use of kinetic parameters to describe quality degradation in frozen foods.

Based on theoretical considerations, quality life and activation energy are related by the equation:

ln tQ= ln B+Ea/R· 1/T

where B is a function of the pre‐exponential of Arrhenius equation, initial and end point quality magnitude.

Reasons for some TTT data to deviate from this relationship are:

Different standards for measuring quality lives of different storage temperatures or experiments.

Negative effect of temperature.

Variations in initial or final quality magnitudes for a given experiment.

Variations in packaging material and other factors influencing the quality magnitude or mode.

ITT experiments are suitable approaches for obtaining activation energy constants, although they are not applicable for determination of reaction order and rate constant. When dealing with overall quality life of several contributing factors, quality life for each component is needed to get a better description. Quality changes in terms of fraction of initial quality magnitude retained can be described by quality life, activation energy, temperature history and the constant, α= CtQ/C0.
HEAT TRANSFER TO WATER AND SOME HIGHLY VISCOUS FOOD SYSTEMS IN A WATER‐COOLED SCRAPED SURFACE HEAT EXCHANGER
Authors: VAN BOXTEL L. B. J. , GOETHART R. L. DE FIELLIETTAZ
Published: February 2007

Heat transfer in a water‐cooled scraped surface heat exchanger has been investigated. The overall heat transfer coefficient in the heat exchanger is composed of three elements: heat transfer coefficient in the coolant jacket, resistance to heat flow in the separation wall and heat transfer coefficient inside the scraped cylinder.

A method for assessing the heat transfer coefficient at the coolant side was developed.

In contrast with studies published elsewhere, heat transfer was investigated with food systems which are non‐newtonian and possess a complicated and unknown flowing behavior at higher shear rates.

For water and three starch‐based food products (starch content 12–18%) the heat transfer coefficients inside the scraped cylinder were measured for shaft speeds ranging from 1.67 to 10 revolutions/s. The experimental results were compared with heat transfer coefficients calculated with a model based on the penetration theory. For the starch‐based products, in general, no consistent interactions between mass flow rates and internal heat transfer coefficients were observed. In the shaft speed range studied heat transfer coefficients at scraped surface varied from 3200 to 7800 W/m2 K for water, from 500 to 3150 W/m2 K for velouté sauce, from 670 to 1330 W/m2 K for roux and from 780 to 1900 W/m2 K for ragout.
MODELING A TWIN SCREW CO‐ROTATING EXTRUDER1
Authors: YACU W. A.
Published: February 2007

This work desribes the simulation of a twin screw co‐rotating extruder. Based on a uni‐directional analysis, the temperature and pressure profiles within the extruder are predicted from knowledge of feed and extruder characteristics. A non‐Newtonian, non‐isothermal viscosity model is used to describe the materials rheology. the analysis covers an evaluation of conditions within the solid conveying zone, the melt pumping zone and a melt shearing zone achieved by reverse screw elements. the total energy input (both mechanical and through the barrel) is also evaluated. the simulation work has proved satisfactory in the design and optimization of extruder operation.
SOLAR OSMOVAC‐DEHYDRATION of PAPAYA
Authors: MOY J. H. , KUO M. J. L.
Published: February 2007

A solar osmotic dryer was designed and constructed to test the utilization of solar energy in the two‐step osmovac‐dehydration of papaya. Drying rates measured in solar versus nonsolar osmotic dehydration experiments showed that solar osmotic drying had higher drying rates and sucrose uptake in the papaya samples (0.6 cm thick × 4 cm long × 2 cm wide) than in the nonsolar runs. In separate experiments, drying rates from solar vacuumdrying (as a second step of the osmovac‐drying process) were about twice those of nonsolar vacuum‐drying. Drying rates of both solar and nonsolar vacuum‐drying reached the end of the constant‐rate period in about 3 h. Sensory qualities of solar osmovac‐dried papaya were comparable to those of vacuum‐dried or solar osmotic‐nonsolar vacuum‐dried. These results suggest the possibility of drying rate increase and quality retention in utilizing solar energy in the osmovac‐dehydration process.
CORRELATIONS FOR the CONSISTENCY COEFFICIENTS of APRICOT and PEAR PUREES
Authors: ILICALI COSKAN
Published: February 2007

Two correlations for the consistency coefficients of apricot and pear purees have been developed. the consistency coefficient for the apricot puree within the given experimental range can be represented as K = 3.7 × 10−6e1500/T(%TS)3.5 and for the pear puree, K = 3.1 × 10−6e1500/T(%TS)3 Experimental values obtained from the literature are compared with the predictions obtained using the above equations. the level of agreement is generally satisfactory. It is recommended that the consistency coefficients for fruit purees be determined at known dissolved solids and insoluble solids content.
USE OF TIME‐TEMPERATURE DATA DURING FLUIDIZED BED FREEZING TO DETERMINE FROZEN FOOD PROPERTIES
Authors: MARIN M. , RIOS G. M. , GIBERT H.
Published: February 2007

Most of the methods proposed in literature for freezing time calculation require the previous knowledge of the enthalpy change and thermal conductivity of frozen materials. Ordinarily these properties are not easy to obtain, and often need a special approach depending on the process under consideration.

This paper deals with a new and simple method that affords an estimation for Fluidized Bed Freezing of small food pieces (20‐40 mm) immersed in a cold fluidized bed of fine inert particles. Based upon Plank equation and temperature‐time recordings, the method more particularly yields the latent heat to be removed for bringing the product below the freezing poatt and the thermal conductivity of the matter in this final state. The associated percentage of water actually frozen during operation may be also determined.

With the help of this technique properties have been determined for various fruits and vegetables (banana, carrot, potato, turnip and cucumber). The values that have been found agree well with literature data: latent heats correspond to the latent heat required to freeze 80% of the water in the products, and thermal conductivities lie between 1 and 2 W/m °C. Helpful correlations for Fluidized Bed Freezing time calculation are proposed that simply relate these properties to the total water content of materials.
RELATION BETWEEN MECHANICAL PROPERTIES of APPLE FRUIT and SENSORY QUALITY
Authors: VAN WOENSEL G. , WOUTERS A. , DE BAERDEMAEKER J.
Published: February 2007

In order to select those parameters determining the apple fruit acceptability for the consumer, fruit texture was measured using several methods. Three methods were selected to do tests on Golden Delicious apples with differing acceptability for the consumer. the three methods used were an uniaxial compression test on cylindrical fruit samples, a resonance test on cylindrical apple specimen, and a non‐destructive dynamic test.

Most useful information is given in the dynamic tests. the apparent elastic modulus derived from the destructive dynamic test and the stiffness factor (S = f2m2/3) as well as the damping ratio at the spheroidal vibration mode of a whole apple derived from nondestructive dynamic tests seem to be parameters correlating highly with the apple fruit acceptability, hence with the internal quality, for the consumer.
MOISTURE EQUILIBRIA of SOME DEHYDRATED CASSAVA and YAM PRODUCTS
Authors: ONAYEMI O. , OLUWAMUKOMI M.O.
Published: February 2007

The moisture content for optimum stability of the products made from cassava (gari and lafun) and yam (elubo and instant pounded yam flour) were calculated from equilibrium moisture data using the BET equation.

The sorption properties for products (lafun and elubo) that were not precooked prior to final drying were similar. the moisture content for optimum stability of the cassava and yam products lies between 6.5–8.0% under conditions that simulated distribution and marketing of the products.

Storage tests confirm that the calculated moisture values from the sorption isotherms indicate that aside from differences in the pretreatment conditions the poor keeping qualities of the products could be improved by further drying to moisture levels of 6.5–8.0% prior to packaging in moisture proof containers.
A SIMPLIFIED ANALYTICAL MODEL FOR FREEZING TIME CALCULATION IN FOODS
Authors: ILICALI C. , SAGLAM N.
Published: February 2007

A simplified analytical model for the freezing time prediction of simple‐shaped foodstuffs was developed. It was assumed in the model that the solution to the unsteady state, unidirectional heat conduction equation with constant thermophysical properties was valid during cooling and freezing. the latent heat effects during freezing were incorporated into an effective diffusivity term. the predictions of the model were compared to the available experimental data on freezing of infinite slabs, infinite cyliners and spheres, and to the experimental data obtained in this research for the freezing of apples. the level of agreement between the predictions and the experimental data was quite satisfactory.
FREEZING TIME CALCULATION FOR PRODUCTS WITH SIMPLE GEOMETRICAL SHAPES
Authors: LACROIX C. , CASTAIGNE F.
Published: February 2007

A simple model is proposed to estimate freezing times of foodstuffs of simple geometrical shapes (infinite flat slabs, infinite cylinders, spheres, rectangular parallelepipeds and finite cylinders). This model combines Plank's equation for change of phase period with the unsteady heat transfer solutions for cooling periods before and after phase change.

The total freezing time is obtained by the determination and the summation of the precooling, phase change and tempering times. the results produced are at least as accurate as or better than any of the previous methods, including regression formula and finite difference computations.

Tables required for fast and accurate predictions of freezing times of foodstuffs with this method are provided.
MATHEMATICAL MODELLING of RADIAL CONTINUOUS CROSSFLOW AGRICULTURAL DRYERS
Authors: CENKOWSKI STEFAN , SOKHANSANJ SHAHAB
Published: February 2007

Circular grain dryers in which grainflow is continuous and airflow is in radial direction are widely used as on‐farm grain dryers. A concurrentflow drying model is adapted to the crossflow drying of the moving bed of grain. the simulated air and grain temperatures and moisture contents of wheat and corn samples were compared to the experimental drying of these grains in laboratory dryers. the results show that the model can be used to describe temperature of grain within 1°C and moisture content within 0.3% w.b.
PARTICULATE HEAT TRANSFER to CANNED SNAP BEANS IN A STERITORT
Authors: FERNANDEZ C.L. , RAO M.A. , RAJAVASIREDDI S.P. , SASTRY S.K.
Published: February 2007

Connective heat transfer coefficient at the fluid‐particle interface was determined for cut green beans in 303 × 406 cans processed in an agitated retort (FMC Steritort) by measuring the temperature of an aluminum bean and that of the surrounding Newtonian fluid. Four retort reel velocities, two sizes of aluminum beans, and six particle/fluid ratios were employed. Several correlation forms were tested. A correlation was developed in terms of the j‐factor, Reynolds number (Re), and shape factor with an R2 of 0.785. the particle's shape was a critical factor in the heat transfer correlations. the fluid‐particle heat transfer rate increased with an increase in rotational velocity of the retort.
STRENGTH CHARACTERISTICS of PRESSURIZED CANS
Authors: BREWBAKER PHILIP L. , HENDERSON JERALD M.
Published: February 2007

To study the strength advantages of pressurized cans used for food packaging, two indicators of can strength, maximum axial load and maximum external pressure, were investigated experimentally. Unbeaded 303 × 406 steel cans having several thicknesses and tempers with various internal pressures were tested. Also tested were beaded steel cans and aluminum cans with 206 × 406 dimensions. Failure of the cans was by both buckling and yielding. the results indicated that steel can thicknesses could be significantly reduced, and beading eliminated, by using internal pressure to supplement can strength.
A GENERALIZED VISCOSITY MODEL FOR EXTRUSION of PROTEIN DOUGHS1
Authors: MORGAN R.G. , STEFFE J.F. , OFOLI R.Y.
Published: February 2007

A theoretical model to predict the apparent viscosity of protein doughs during thermal processing involving heat induced denaturation is presented. the model allows viscosity prediction based on the effects of temperature‐time history, strain history, temperature, shear rate and moisture content. Data from several sources have been considered in investingating the performance of the model. the approach facilitates an understanding of the mechanisms associated with protein texturization during extrusion.
FLOW BEHAVIOR of TOMATO SAUCE WITH OR WITHOUT PARTICULATES IN TUBE FLOW1
Authors: BHAMIDIPATI SATYANARAYANA , SINGH RAKESH K.
Published: February 2007

Viscosity and density are two properties of fluids that are affected by temperature changes. the flow behavior of tomato sauce (7° and 14° Brix) in a tube viscometer was studied at varying concentrations of added particulates (2 and 5 wt%) at temperatures in the range of 70 to 95°C. the results indicate that the Power Law model described the flow behavior of the non‐Newtonian fluids better than the Casson model. the effects of temperature, concentration of carrier fluids and particulates on the flow behavior indices and viscosity was studied. the effect of temperature on the flow behavior index (n) and consistency index (K) were modeled as exponential relationships. the values of n and K for 7° Brix sauce ranged from 0.30 to 0.86 and 0.04 to 0.34, respectively. For the 14° Brix sauce these values were 0.27 to 0.53 and 0.20 to 0.60 respectively. the values of n decreased and K increased with increase in concentration of solids and particulates. the relative changes in K and n were lower for higher concentrations of solids and particulates. It was found that temperature had a greater effect on K than on n.

The effects of temperature on viscosity was modeled as an Arrhenius type equation from which the activation energies were calculated. the combined effects of temperature, concentration of solids in the sauce and added particulates on apparent viscosity can be predicted by a nonlinear model.
REVERSE OSMOSIS CONCENTRATION of GREEN TEA JUICE
Authors: QUI ZHANG SHI , MATSUURA TAKESHI , CHAN KAM
Published: February 2007

The reverse osmosis concentration of green tea juice was attempted by using membranes prepared from different polymeric materials. the pore sizes of the membranes were also changed in order to investigate the effect of the pore size on the membrane performance. Special attention was focused on the removal of caffeine from the tea juice while retaining other components such as polyphenols and amino acids. Since severe membrane fouling was observed while tea juice was treated at high concentrations, an attempt was made to describe the membrane fouling by a modified gel model that includes the effect of the interaction between the membrane and the tea juice components.
SIMULATION BASED PERFORMANCE ANALYSIS of CRAWFISH PROCESSING OPERATIONS1
Authors: ESCOBAR F.A. , WELLS J.H. , WAIKAR A.M.
Published: February 2007

A detailed model of crawfish processing operations was developed using the SLAM II simulation language. the simulation model was used to compare overall plant performance for two crawfish cooking schemes, boiling water and steam infusion, and to evaluate processing parameters for different plant capacities. For all the range of operating levels included in this study (2,400‐19,000 lb of live crawfish/day or 360‐2,900 lb of tail meat/day), the steam infusion cooking scheme rendered shorter processing times than those required by the boiling water cooking scheme. Moreover, the batch sizes and amount of resources used are smaller for the steam infusion cooking scheme. the simulation model is a valuable tool to analyze the performance of crawfish plants as well as to determine the impact of changes in technology on the overall process.
EVAPORATION IN A HORIZONTAL THIN FILM SCRAPED SURFACE HEAT EXCHANGER
Authors: ABICHANDANI H. , SARMA S. C.
Published: February 2007

Literature surveys have revealed inadequate information on heat transfer characteristics during evaporation in straight‐sided horizontal thin film scraped surface heat exchangers (SSHE). the evaporation of water, concentration of milk and dehydration of cream (30–40% total solids) at different rotor speeds, number of blades, flow rates and temperature differentials were studied in 108 tests with objectives to develop a predictive equation for overall heat transfer coefficient and to study its variation with regard to above parameters in the light of proposed mechanism governing fluid flow, film formation and heat transfer. Data were processed in HCL System‐4 computer to fit in quadratic form by method of least squares. Experiments were conducted at higher temperatures compared to those encountered in milk evaporators. the information would be useful in designing SSHE for processing several Indian dairy products.
ELECTRICAL CONDUCTIVITY of SELECTED JUICES: INFLUENCES of TEMPERATURE, SOLIDS CONTENT, APPLIED VOLTAGE, and PARTICLE SIZE1
Authors: PALANIAPPAN SEVUGAN , SASTRY SUDHIR K.
Published: February 2007

A device was developed to determine the electrical conductivities of foods under ohmic or conventional heating conditions. Orange and tomato juices (serum and various solids contents) were tested in the device. the electrical conductivity of juices increased with temperature and decreased with solids content. the temperature dependence of conductivity was linear, both under conventional and ohmic heating. Experiments on suspensions of carrot juice solids, and polystyrene spheres in sodium phosphate solution showed an increase in electrical conductivity of the suspension with decreasing particle size.
CONSEQUENCES of FOULING and MACROMOLECULE ADSORPTION ONTO ULTRAFILTRATION MEMBRANE FOR PINEAPPLE JUICE PROCESSING
Authors: DOKO M.B. , VALENTE M. , JACOB M. , PUECH A.
Published: February 2007

Pineapple juice samples were ultrafiltrated using a polysulfone 10,000 molecular weight cut‐off (MWCO) membrane. However, to facilitate operations, the ultrafiltration experiments were preceeded by fractionation of juice samples using sequentially Microfiltration/Diafiltration and Ultrafiltration/Diafiltration with 8 μm; 0.4 μm; 0.2 μm and 0.1 μm membranes, using three specific experimental procedures. the 10,000 MWCO membrane was cleansed using a 40°C IN NaOH solution for a minimum of 30 min, to restore optimal membrane water permeation flux. the effects of selective fractionation processes, pretreatments (using antifoaming agent, hemicellulase, and ammonium sulfate saturation), on permeation rates, concentration levels, protein rejection and protein yields were determined. Water permeation fluxes, measured before and after each UF operation showed a dramatic flux drop from 313 L/hm2 to 91 L/hm2 within seven successive 10,000 MWCO membrane experiments. This occurred inspite of suitable membrane washing conditions, pretreatments and selective fractionation processing of samples. the modification, mainly due to fouling, of the integrity of the 10,000 MWCO membrane relative to concentration level was investigated.
NONDESTRUCTIVE MEASUREMENT of TRANSIENT MOISTURE PROFILES and the MOISTURE DIFFUSION COEFFICIENT IN A POTATO DURING DRYING and ABSORPTION BY NMR IMAGING
Authors: RUAN RONGSHENG , SCHMIDT SHELLY J. , SCHMIDT ARTHUR R. , LITCHFIELD J. BRUCE
Published: February 2007

A nondestructive method to measure the internal moisture distribution and to determine the effective moisture diffusion coefficient for a potato during drying and absorption was developed using NMR imaging and numerical modeling techniques. the coefficients obtained were 1.04 to 7.28 × 10−10 m2/s, for moisture contents between 40% and 55% (wb), during drying with a sample temperature of 40°C; and were 9.78 × 10−12 to 2.33 × 10−11 m2/s, for moisture contents between 56% and 60%, during absorption at 23°C.
SETTLING CHARACTERISTICS of CARROT PARTICLES IN VERTICAL PIPELINES
Authors: McKAY G. , MURPHY W.R. , JODIERI‐DABBAGHZADDEH S.
Published: February 2007

The settling characteristics of carrot and plastic cylindrical particles has been investigated. the settling velocities in hindered and unhindered environments have been determined for particles of different diameters and aspect ratios.

In settling studies using single particles, there was an initial increase in falling velocity with increasing aspect ratio. However, for aspect ratios above 2:1, the settling velocity reached a constant value, which then began to decrease as a function of the particle length. the results for particles subjected to hindered settling did not correlate well with existing literature except for low aspect ratio systems. Wall effects were studied and observed for particles with aspect ratios greater than 4.25:1. Fluidization data were compared with the results from settling tests for similar systems, and it was observed that the terminal falling velocity of a particle is mainly affected by drag only, but in fluidization, the transportation velocity is influenced by a combination of drag, wall and interparticle effects.
EFFECT of DIFFERENT TEMPERATURE CONTROL METHODS ON HEATING TIME and CERTAIN QUALITY PARAMETERS of OVEN‐ROASTED BEEF
Authors: MIELCHE MARTIN M.
Published: February 2007

Four different methods of oven roasting beef were studied. Twelve semi‐tendinosus muscles were transversely divided, and the 24 subsamples were allocated to 4 cooking methods: High temperature roasting (HTR) with a constant oven temperature of 170C; low temperature roasting (LTR) with a constant oven temperature of 120C; maximum temperature roasting (MTR) with maximally 70C 1 cm below the roast surface and temperature difference roasting (TDR) with constantly 50C between the oven and 1 cm below the roast surface. Quality parameters measured were cooking loss, Warner‐Bratzler shear parameters and taste panel ratings.

Mean heating times of HTR, LTR, MTR and TDR were 69, 100, 79 and 157 min, respectively. Most of the quality parameters by HTR were significantly poorer as compared with the other methods, while differences between LTR, MTR and TDR were small.

Surface heat transfer coefficient was estimated as 14.1 W/m2C. Heating times were predicted with a maximum deviation of 10%.
APPLICATION of an ENZYME KINETICS BASED RESPIRATION MODEL to CLOSED SYSTEM EXPERIMENTS FOR FRESH PRODUCE
Authors: HAGGER P.E. , LEE D.S. , YAM K.L
Published: February 2007

An approach was developed to use a respiration model, based on enzyme kinetics principle, along with the closed system method for generating respiration rates of fresh produce as a function of O2 and CO2 concentrations. to verify this approach, experiments were conducted to measure the respiration rates of cut broccoli contained in closed jars at 0, 7, 13 and 24C. the respiration model was found to fit the experimental data very well, and the model parameters were estimated using multiple linear regression analysis. Another experiment was also conducted with a permeable package containing cut broccoli at 13C, and the experimental respiration rates were found to compare well with those predicted using the model parameter values estimated above.
PRACTICAL FLUIDS FOR FOOD RHEOLOGY and PROCESS ENGINEERING STUDIES
Authors: HULL M. , STEFFE J.F.
Published: February 2007

Corn syrups were shown to have potential for use as Newtonian calibration fluids in some applications where established standard oils are not suitable. Theological analyses, using both steady and dynamic shear conditions, demonstrated that corn syrup viscosities are as constant as those of standard calibration oils. Some syrups showed significant elasticity that may be due to their tendency to dry upon exposure to air during testing. With careful attention to shelflife and protection from air drying, corn syrups can be used in many food engineering problems where equipment calibration and process standardization are needed.