bluuebunny/crossref_metadata_2025 huggingface dataset:
PARTICLE HEAT TRANSFER COEFFICIENTS UNDER VARIOUS RETORT OPERATING CONDITIONS WITH END‐OVER‐END ROTATION
Authors: SABLANI S.S. , RAMASWAMY H.S.
Published: February 2007

Forced convection heat transfer in cans was studied experimentally during end‐over‐end sterilization in a full‐immersion, hot‐water rotary sterilizer. A polypropylene spherical particle (diameter = 19 mm) was suspended in a high temperature bath oil (Newtonian liquid) using a flexible fine‐wire thermocouple attached to the can wall providing uninhibited heat transfer conditions. the overall heat transfer coefficient, U, was determined using a lumped capacity heat balance approach and the fluid‐to‐particle heat transfer coefficient, hfp, was determined from transient temperature data at the center of the particle using a finite difference computer simulation. the effects of retort temperature (110 to 130C), rotational speed (0 to 20 rpm), radius of rotation (0 to 27 cm) and can headspace (6.4 and 10 mm) were examined on the associated heat transfer coefficients. Higher heat transfer coefficients were obtained with increasing values of all four variables, and the effects of rotational speed and headspace were more significant than those of retort temperature and radius of rotation. U values ranged from 120 to 187 W/m2. K and hfp values ranged from 23 to 145 W/m2. K depending on the operating conditions.
SELECTION OF VARIABLE RETORT TEMPERATURE PROCESSES FOR CANNED SALMON
Authors: DURANCE TIMOTHY D. , DOU JINGLE , MAZZA JOSEPH
Published: February 2007

Variable retort temperature processes (VRT), in which retort temperature is a function of time, were developed for sterilization of Pacific salmon in 307 × 115 steel cans, with objectives of minimizing loss of quality criteria such as surface quality or thiamine, or minimizing process time, all while maintaining constant center‐point lethality (F). A finite difference computer model of conduction within a finite cylinder was used to test different temperature‐time profiles. Processes were constrained to include steam vent schedules and to exclude temperature decrease during the heating process as well as temperature modulation during cooling, thereby improving compatibility with typical salmon canning facilities. Rho, the fraction of total lethality accumulated at steam‐off time, was found to be a function of final unaccomplished temperature, retort temperature, salmon thermal diffusivity and container geometry. The search for favorable processes was aided by Random Centroid Optimization (RCO). Minimum surface cook in constant retort temperature (CRT) processes varied with retort temperature and z of surface quality, but the best VRT process was consistently better than the best CRT process. VRT reduced operator's process time from 64 min to 54 min and maintained equal F0 and surface quality. Thiamine losses were reduced from 19.6% loss by CRT to 16.8% loss by VRT.
DYNAMIC GAIN MATRIX APPROACH TO MODELING OF DYNAMIC MODIFIED ATMOSPHERE PACKAGING SYSTEMS4
Authors: ÖZER E. , WELLS J.H. , McMILLIN K.W. , HO C.‐P. , HUANG N.‐Y.
Published: February 2007

Variations in food and biological systems create nonlinear interactions that increase complexity of mathematical models. A multivariable correlative mathematical modeling strategy, dynamic gain matrix (DGM) method, was derived using advanced process control concepts and it was applied to describe quality changes in beef loin steaks with postmortem fabrication time and modified atmosphere packaging (MAP) conditions altered by dynamic gas exchange. DGM was used for modeling of dynamic MAP to satisfy the special modeling requirements of relationships between the processing and packaging variables and quality parameters through consideration of multivariable interacting deterioration mechanism in mathematical terms. A normalization method was also developed and applied to eliminate initial condition effects arising from meat source differences. A total of 960 data points were analyzed, and the model is reported as a series of first order differential equations with respect to retail display time to describe changes in color, pH and microbial population as functions of postmortem fabrication time, distribution gas composition, gas exchange time and retail gas composition. The model was optimized to minimize prediction sum of residual errors, and a pairing and control strategy was proposed to be used for optimum control of quality parameters for a chosen display time by manipulation of processing and packaging variables. The strategy developed has specific use for prediction and design of dynamic gas exchange MAP systems as well as potential use in similar biological engineering systems.
HEAT TRANSFER TO PARTICLES IN CANS WITH END‐OVER‐END ROTATION: INFLUENCE OF PARTICLE SIZE AND CONCENTRATION (%V/V)
Authors: SABLANI S.S. , RAMASWAMY H.S.
Published: February 2007

The heat transfer coefficients (U and hfp) associated with particulate fluids in cans were evaluated with suspended Nylon particles, during end‐over‐end rotation. Can rotation speed (10 to 20 rpm), particle diameter (19 to 25 mm) and particle concentration (single particle to 40% v/v) were studied as variables using fluids of two different viscosities (1.0 × 10−6 and 1 × 10−4m2/s). Particle transient temperatures were measured by placing a flexible thermocouple attached to the particle, allowing particle motion inside the can. Transient heat conduction equations for a spherical particle with convective boundary condition at fluid‐particle interface were numerically solved to obtain hfp. An overall heat balance equation was solved to obtain U. The hfp values varied from 170 to 1165 W/m2.K with oil and 175 to 1550 W/m2.K with water depending upon process conditions. The U values varied from 110 to 220 W/m2.K with oil and 480 to 800 W/m2.K with water. The hfp increased 10 to 60% with decreasing particle diameter from 25 to 19 mm while it increased about 3 folds as the particle concentration changed from a single particle to 30%. Further increase in panicle concentration to 40% decreased the hfp between 5 and 20% depending upon processing conditions. The effects of particle size and particle concentration on the U were similar to those obtained with hfp with lower magnitudes.
PRODUCTION OF COWPEAS IN TOMATO SAUCE: ECONOMIC COMPARISON OF PACKAGING IN CANNING AND RETORT POUCH SYSTEMS
Authors: TAIWO K.A. , AKANBI C.T. , AJIBOLA O.O.
Published: February 2007

The economic feasibility of using the retort pouch as an alternative to the canning system for packaging and processing of cowpeas in tomato sauce was evaluated using the Net Present Value (NPV) and Internal Rate of Return (IRR) methods assuming a uniform cashflow over a 10‐year plant life. Cost estimates for the alternative packaging system were based on an equal mass flow rate of processed cowpea, i.e., 360 cans/min. The retort pouch system required a larger fixed capital investment than the canning system. The cost of cans accounted for a larger percentage of the raw material cost than the pouch. Energy costs in processing for both systems contributed very little to the total operating costs. In addition, all the variable operating costs were higher in the pouch system than in the cans for one 8‐h shift operation such that the cost of producing each unit was of product higher with the pouch than in the can. Increasing the number of shifts to two increased the economic performance of both systems at the same time reducing product cost. Results of the NPV and IRR indicated that capital investment on the canning line would be more profitable than the pouch system.
THE THERMAL PROPERTIES OF POTATOES AND CARROTS AS AFFECTED BY THERMAL PROCESSING1
Authors: MURAKAMI EDGAR G.
Published: February 2007

The effects of processing on the thermal properties of white potatoes and carrots were studied. The test samples were blanched, boiled, cooked and canned. Whole potato tubers were baked to study the effects of starch gelatinization. The thermal conductivity (k) and density (ρ) were measured and the specific heat (cp) and thermal diffusivity (α) were calculated. Results showed that in general, α initially decreased and then increased during processing. Test samples were found to have a gain in α when their moisture content increased by more than 9%. The α of potatoes decreased after canning and increased after boiling. In carrots, a similar trend was also observed but to a lesser degree. The k of potatoes was unaffected after blanching or cooking. In all the processing baking study showed that gelatinization significantly decreased the k of potatoes.
PHYSICAL AND AERODYNAMIC PROPERTIES OF MAKHANA
Authors: JHA S.N. , KACHRU R.P.
Published: February 2007

Makhana is a popped kernel of gorgon nut (Euryale ferox) and is considered a delicious food item in India. It is, presently, sorted, graded and processed manually. To develop any kind of mechanized system for these purposes, physical data are required and thus, test weight, bulk density, true density, porosity, angle of repose and coefficient of friction of different grades of makhana were determined using standard techniques at moisture contents ranging from 5 to 20% (dry basis). The data were used to develop correlation equations that predict these physical properties as a function of moisture content of makhana. The spatial dimensions and aerodynamic properties were also determined. The average diameter of makhana varied between 18.4 mm to 12.4 mm with the sphericity between 0.581 to 0.967; and other physical properties varied quadratically with moisture content. The terminal velocity and drag coefficient of makhana at 8% moisture content (dry basis) varied between 4.48 to 6.10 m/s and 0.62 to 1.06, respectively.
DETERMINATION OF FLUID‐TO‐PARTICLE HEAT TRANSFER COEFFICIENTS FOR ROTATING PARTICLES1
Authors: CHAKRABANDHU K. , SINGH R.K.
Published: February 2007

Fluid‐to‐particle heat transfer coefficients (hfp) were determined for stationary and rotating potato‐alginate cubes heated by carboxymethylcellulose solutions in an aseptic processing system. Fluid temperature, fluid average velocity, CMC concentration, and particle size were varied. In the stationary particle case, the slip generalized Reynolds numbers (Regs) ranged from 1.3 to 6.7. For the rotating particles, Regs ranged from 0.91 to 5.0 and the generalized rotational Reynolds numbers (Regr) ranged from 6.0 to 33. The hfp ranged from 120 W/m2°C to 2400 W/m2°C and from 360 W/m2°C to 4300 W/m2°C for stationary and rotating particles, respectively. Particle rotation significantly increased hfp. Fluid temperature, particle size, fluid average velocity, and CMC concentration had significant effects on hfp for both stationary and rotating particles. Using Regs in the dimensionless correlation gave a better prediction of hfp for the rotating particles than using Regr.
VISCOSITY CHARACTERIZATION OF A COMMERCIAL YOGURT AT 5C USING A CUP IN BOB AND A VANE GEOMETRY OVER A WIDE SHEAR RATE RANGE (10−5S−1‐103s−1)
Authors: GERAGHTY RICHARD , BUTLER FRANCIS
Published: February 2007

Equilibrium viscosity data at 5C, over a wide shear rate range (10−5 s−1 ‐103 s−1), are presented for a typical commercially available stirred yogurt. A bob in cup and a vane in cup geometry were used in the work. The vane was manufactured to the same outer dimensions as the bob. A series of constant shear stress creep tests was performed, ranging from 2 Pa to 60 Pa. Equilibrium shear rate values were found for each shear stress. Equilibrium viscosity data obtained with both geometries were of the same order of magnitude. This indicated that slip (wall depletion) effects were not significant with the bob in cup geometry used in the study. Application of existing rheological models showed that the equilibrium viscosity behavior of yogurt may be described using either a power‐law of the form or the Cross equation The Cross model better predicted the almost constant viscosities observed at low shear stresses.
APPARENT THERMAL CONDUCTIVITY, WATER CONTENT, DENSITY, AND POROSITY OF THERMALLY‐PROCESSED GROUND CHICKEN PATTIES1
Authors: MURPHY R.Y. , MARKS B.P.
Published: February 2007

Changes in thermal conductivity, density, and porosity during heating were evaluated for commercially manufactured ground chicken breast patties in a temperature range of 23 to 85C. The thermal conductivity of the meat, heated in a closed container, decreased approximately 8% with increasing temperature. In a separate test series, where water was free to leave the meat during cooking, the water content decreased approximately 15% over the same temperature range. The thermal conductivity of the meat was modeled as a quadratic function of temperature. Changes in the water content were modeled as a linear function of temperature. The solid density increased approximately 6%, and the porosity more than doubled with a temperature increase from 23 to 85C.
IMPROVED VIABILITY OF SPRAY DRIED BREWER'S YEAST BY USING STARCH (GRITS) AND MALTODEXTRIN AS PROCESSING AIDS
Authors: LUNA‐SOLANO GUADALUPE , SALGADO‐CERVANTES MARCO A. , GARCIA‐ALVARADO MIGUEL A. , RODRIGUEZ‐JIMENES GUADALUPE
Published: February 2007

Active dry brewer's yeast was prepared by spray drying (Tout 50 and 60C). Addition of processing aids to the yeast cream was necessary in order to dry at these temperatures. Corn starch (grits) and maltodextrins (DE‐6) two levels of additions (10 and 20%) were used as processing aids. Statistical analyses proved that processing aids concentration, air outlet temperature and rotor speed had significant effects on yeast viability. Dried samples could be preserved at least 4 months stored at 5 and 25C with a loss of 1 and 2 log cycles of viable cells, respectively.
HEAT TRANSFER COEFFICIENT FOR COOKIE SHAPED OBJECTS IN A HOT AIR JET IMPINGEMENT OVEN
Authors: NITIN N. , KARWE M.V.
Published: February 2007

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.
THERMOPHYSICAL PROPERTIES OF PINK GUAVA JUICE AT 9 AND 11°BRIX
Authors: ZAINAL B.S. , RAHMAN R. ABDUL , ARIFF A.B. , SAARI B.N. , ASBI B.A.
Published: February 2007

The effect of temperature on the conservation of pseudoplastic characteristics and on the physical properties of pink guava juice (Psidium guajava L.) variety Beaumont: B‐30 with two different total soluble solids (9°Brix and 11°Brix) was investigated. It was found that the juice exhibits pseudoplastic behavior in the range of shear rate between 40 to 160 s−1 and within pasteurization temperature of 60–90C. While the flow behavior index (n) and density (p) increased, consistency coefficient (K), thermal conductivity (k) and specific heat capacity (Cp) decreased with increasing temperature. The linear regression equations or models for flow behavior index, consistency coefficient, density, thermal conductivity and specific heat capacity were determined with correlation coefficients ranging from 0.75 to 1.00.
DIFFUSION OF BEET DYE DURING ELECTRICAL AND CONVENTIONAL HEATING AT STEADY‐STATE TEMPERATURE1
Authors: LIMA MARYBETH , HESKITT BRIAN F. , SASTRY SUDHIR K.
Published: February 2007

Ohmic heating has been shown to alter mass transfer properties of fruit and vegetable tissue. Diffusion of beet dye from beetroot tissue into a fluid was studied during conventional and ohmic heating as a function of steady‐state temperature. The volume of beet dye diffusing into solution during ohmic heating was enhanced with respect to conventional heating at 42C and 58C, but not at 72C. This can be explained by examining the differences in electrical conductivity of beet tissue at these temperatures during conventional and ohmic heating. At 42 and 58C, the electrical conductivity of beet tissue heated ohmically is higher than the electrical conductivity of beet tissue heated conventionally. At 72C, the electrical conductivities of beet tissue during conventional and ohmic heating are equal. The extent of diffusion in the ohmic case is also positively correlated with applied voltage. These results suggest that food processes involving mass transfer can be enhanced by choosing conditions in which the electrical conductivity of a sample under ohmic conditions is maximized.
PORE SIZE DISTRIBUTION AND STRUCTURE OF A COOKED BEEF PRODUCT AS AFFECTED BY VACUUM COOLING
Authors: McDONALD KARL , SUN DA‐WEN
Published: February 2007

True density, apparent density, and pore size distribution were measured for a vacuum cooled cooked beef product using helium pycnometry and mercury porosimetry. Vacuum cooled samples resulted in the development of high porosity and lower density in comparison to more conventional cooling methods. Pore size distribution for vacuum cooled samples revealed the presence of random pore sizes with no distinct pore size but rather a pore size range of 10 μm to 0.02 μm. It was determined that the vast majority of porosity in vacuum cooled samples was composed of void space volume as distinct to regular pores. Analysis of estimated diffusion coefficients revealed that the efficiency of vacuum cooling is dependent on the development of porosity within the samples during cooling which leads to more efficient cooling times and higher diffusion rates in samples with higher porosity and larger pore size distributions.
NONLINEAR CONSTRAINED OPTIMIZATION OF THERMAL PROCESSING: I. DEVELOPMENT OF A MODIFIED ALGORITHM OF COMPLEX METHOD
Authors: ERDOǦDU FERRUH , BALABAN MURAT O.
Published: February 2007

The complex method, a general and flexible optimization algorithm, was used to determine the optimum process temperature profiles during thermal processing to maximize (optimize) the objective function of volume average retention of thiamine in conduction heated foods with restrictive explicit and implicit constraints. Implicit constraints were the target lethality at the coldest point, and a threshold below which the center temperature must reach at the end of the process. A process temperature range of 5–150C was used as an explicit constraint. Another explicit constraint was that the process temperature had to reach 5C at the end of the process. Control variable for the optimization was process temperature profile discretized at equidistant time steps throughout the process. All calculations were performed using a computer program written in Microsoft Visual Basic V. 6.0. This Windows‐based software calculated the optimum temperature profiles with resulting objective functions and implicit constraints. The developed algorithm for the Complex Method was found to be satisfactorily usable for the optimization of thermal processing of conduction heated foods.
FILTRATION AND FILTER SYSTEM FOR TREATED FRYING OIL
Authors: BHEEMREDDY R.M. , CHINNAN M.S. , PANNU K.S. , REYNOLDS A.E.
Published: February 2007

Used canola oil was treated with commercially available adsorbents (HB 600, Magnasol, and Frypowder) and a UGA blend for flow rate study and oil quality improvement. Viscosity measurements of fresh and used oil indicated that the oil temperature >140C was best suited for active filtration. One percent adsorbent gave better flow rates than 2% except for Frypowder, which showed no difference in flow rates. All the adsorbents significantly improved the oil quality. Most significant improvement was observed in FFA values (15–20% and 24–35% for 1% and 2% adsorbent level, respectively) except for Frypowder, which resulted in least improvement (4 to 7%). Neither increasing the duration of treatment, prior to filtration, from 3 to 6 min, with 3% UGA blend, nor the multipass filtration treatment showed any significant improvement in oil quality. Pressure system was more promising for active filtration than vacuum and gravity systems.
COATING WITH HONEY: A STUDY WITH MODEL SOLIDS
Authors: PATEL BHAVESH K. , BHATTACHARYA SUVENDU
Published: February 2007

Simulation studies on coating of steel balls with honey as well as the rheological measurements were carried out at different moisture contents (20.3–37.7%, dry basis), and temperatures (5–80C). The coating characteristics of honey were judged by the thickness of honey layer, and by the proposed index, dimensionless uptake. Honey possesses extremely high viscosity at low temperatures and/or at low moisture contents. The sensitivity of honey viscosity with temperature was determined by using Arrhenius equation. Enhanced values of dimensionless uptake and thickness were obtained at low temperature‐low moisture combinations. Viscosity of honey for easy handling and coating is in the neighborhood of 103 mPas corresponding to a temperature of 50C.
RESIDUAL GAS VOLUME EFFECT ON QUALITY OF RETORT POUCH WET‐PACK PEARS
Authors: OLIVAS G.I. , RODRÍGUEZ J.J. , SEPÚLVEDA D.R. , WARNER H. , CLARK S. , BARBOSA‐CÁNOVAS G.V.
Published: February 2007

Wet pack pears in retort pouches were studied for six months. Four selected residual gas volumes [10, 15, 20 and 30 cubic centimeters (cc)] were used to determine the influence of residual gas volume on physicochemical and sensory attributes. Three storage temperatures (4.4, 26.7 and 37.8C) were used to carry out an accelerated shelf‐life study. Residual gas of 30 cc promoted faster darkening and higher ascorbic acid degradation than the rest of the volumes studied (α≤ 0.01). No significant effect of residual gas volume was found on any other attribute analyzed. Temperature accelerated the consumption of remaining oxygen in the pouches, degradation of ascorbic acid, formation of 5‐hydroxymethyl‐2‐furaldehyde (HMF) and 2‐furaldehyde, and softening of pears. Calculated activation energies (Ea) for HMF and 2‐furaldehyde formation, ascorbic acid, and color degradation were 35, 31.1, 29.8, and 10.4 kcal/mol, respectively. Residual gas volume of 20 cc was the maximum volume studied that accomplished the desired shelf‐life for this product.
MODELING HEAT EFFICIENCY, FLOW AND SCALE‐UP IN THE COROTATING DISC SCRAPED SURFACE HEAT EXCHANGER
Authors: FRIIS ALAN , SZABO PETER , KARLSON TORBEN
Published: February 2007

A comparison of two different scale corotating disc scraped surface heat exchangers (CDHE) was performed experimentally. The findings were compared to predictions from a finite element model.

We find that the model predicts well the flow pattern of the two CDHE's investigated. The heat transfer performance predicted by the model agrees well with experimental observations for the laboratory scale CDHE whereas the overall heat transfer in the scaled‐up version was not in equally good agreement.

The lack of the model to predict the heat transfer performance in scale‐up leads us to identify the key dimensionless parameters relevant for scale‐up.
THE INFLUENCE of FIELD STRENGTH, SUGAR and SOLID CONTENT ON ELECTRICAL CONDUCTIVITY of STRAWBERRY PRODUCTS
Authors: CASTRO I. , TEIXEIRA J.A. , SALENGKE S. , SASTRY S.K. , VICENTE A.A.
Published: February 2007

The effects of field strength, soluble solids (from 14 to 59.5 °Brix) and particle size (using two size distributions) on electrical conductivity were investigated. Electrical conductivity increased with temperature for all the products and conditions tested following linear or quadratic relations. Electrical conductivity was found to vary greatly between strawberry‐based products. an increase of electrical conductivity with field strength was obvious for fresh strawberries and strawberry jelly but not for strawberry pulp, probably due to the presence of texturizing agents. This parameter decreases with the increase of solids and sugar content. For some of the formulations tested (solid content over 20% w/w and over 40 °Brix) a different design of ohmic heater may be necessary because of the low values of electrical conductivity.
DIMENSIONLESS CORRELATION FOR ESTIMATING INTERNAL PRESSURE IN THIN‐WALLED ALUMINUM CONTAINERS DURING THERMAL PROCESSING
Authors: AWUAH G.B.
Published: February 2007

The need for creating container initial pressure, overpressure requirements and maintenance during thermal processing of thin‐walled aluminum containers is briefly discussed. the initial pressure within containers was achieved by injecting liquid nitrogen (LN2) into the container headspace (0.5, 0.75 and 1 in.) prior to seaming. Experiments were conducted using a computer‐controlled retort with water‐immersion as heating medium, and temperatures ranging from 241 to 261F. Product initial temperature varied from approximately 45 to 135F. Container internal time‐pressure history during processing was monitored using a remote pressure sensor mounted within the container. Using water as model food, a dimensionless correlation that related the maximum cortainer pressure to product headspace, initial temperature and pressure was developed. Increasing retort temperature increased the maximum container internal pressure, while increasing product initial temperature decreased the maximum internal pressure developed within the container processing. the effect of product initial temperature on the maximum internal pressure was attributed to the amount/level of entrapped gasses present. Developed correlation using water predicted the internal pressure for 5% bentonite suspension with marginal errors (2 to 7%). However, the model failed to predict the maximum pressure for oil‐filled containers.
ELECTRIC SENSOR FOR PROMPT MEASUREMENT OF MOISTURE CONTENT IN SOLID FOOD PRODUCTS
Authors: RYWOTYCKI RYSZARD
Published: February 2007

Originally designed sensor for electrical measurement of moisture content in comminuted food was presented. Equations were formulated to demonstrate the dependence of tested sample electrical resistance on resistivity (specific resistance) of food as well as the dependence of investigated sample electrical capacitance on permittivity of food. Experiments were carried out to determine moisture content in wheat flour, potato starch, and raw pork loin serving as examples. The results of these measurements were compared with the results obtained using conventional gravimetry. The measurement of moisture content lasted for between 3 to 5 s, and the time used for a sample preparation was not longer than 60 s. An advantage of the designed sensor of moisture content is that the density of the investigated food sample does not affect the measurement results.
PROPERTIES of CROSS‐LINKED STARCH PRODUCED IN A SINGLE SCREW EXTRUDER WITH and WITHOUT A MIXING ELEMENT
Authors: SEKER M. , SADDIKOGLU H. , HANNA M.A.
Published: February 2007

Starch was extruded with sodium hydroxide and sodium trimetaphosphate in order to cross‐link it in a single‐screw extruder with and without a mixing element at constant screw speed of 90 rpm in the first set of experiments and at similar mean residence time controlled by screw speed in the second set of experiments. For the screw without mixing element in the second set of experiments, screw speed was adjusted to give the similar residence time as the single‐screw extruder with mixing element at 220 rpm. Phosphorus content and pasting curves of extrudates showed that starch was cross‐linked during extrusion. Replacing the screw without mixing element by the screw with mixing
CHARACTERISTIC DRYING CURVE and MATHEMATICAL MODELING of THIN‐LAYER SOLAR DRYING of PRICKLY PEAR CLADODE (OPUNTIA FICUS INDICA)
Authors: LAHSASNI S. , KOUHILA M. , MAHROUZ M. , MOHAMED L. AIT , AGORRAM B.
Published: February 2007

Thin‐layer solar drying experiments were conducted for the prickly pear cladode grown in Marrakech, Morocco. the experimental drying curves obtained show only a falling rate period. the results verified, with good reproducibility, that the drying air temperature is the main factor in controlling the drying rate. the expression of the drying rate equation was determined empirically from the characteristic drying curve. Eight different drying models were compared according to their correlation coefficient (r2) to estimate solar drying curves. the Page model could satisfactorily describe the solar drying curves of cladode with an r2 of 0.9995. the coefficient of this model could be explained by the effect of drying air temperature with an r2 of 1.0000.
TEXTURE OF CARROTS
Authors: HOWARD P. L. , HEINZ D. E.
Published: February 2007

Abstract Shear and compression strengths of individual carrots were measured with the Instron Universal Testing Machine. Compression correlated highly, but shear poorly, with sensory hardness as judged by compressing and flexing. The study confirmed the usefullness of the coefficient of compression in predicting textural quality of carrots.
FAT CRYSTALS AND THE FLOW RHEOLOGY OF BUTTER AND MARGARINE
Authors: PARKINSON C. , SHERMAN P. , MATSUMOTO S.
Published: February 2007

Abstract The viscosities of fat crystals extracted by 1 % Aerosol O.T. from butter and margarine have been studied using a Weissenberg Rheogoniometer. By applying the Brodnyan (1959) equation for non‐spherical particles to the viscosity data at high rates of shear, after correcting for secondary flow phenomena, it was deduced that the axial ratios of the margarine fat crystals were between 3.05 and 3.94, with the fat crystals from butter lying midway between the two extremes. By applying viscosity equations of the exponential type to such data, it should be possible to calculate the viscosity of butter and margarine at very high rates of shear when the viscosity of the liquid oil in the fat phase and the volume concentration of water drops are known. This information could be useful for predicting the spreadability characteristics of butter and margarine.
LINEARIZATION OF EMPIRICAL RHEOLOGICAL DATA FOR USE IN COMPOSITION CONTROL OF MULTICOMPONENT FOODSTUFFS
Authors: DRAKE BIRGER , NÁDAI BÉLA
Published: February 2007

Abstract An empirical measure of viscosity, which is often far from being a linear function of composition, was used together with refractive index to build up a function which bears a linear relationship to the composition of tomato paste‐water‐sucrose mixtures. The new function can be used directly for rapid composition control by linear vector‐vector transformation.
WHITHER RHEOLOGY IN PHARMACY?*
Authors: WARBURTON B.
Published: February 2007

Abstract The application and future development of some rheological techniques in pharmaceutical formulation are reviewed. The state of the subject is illustrated with examples drawn from the formulation of injections, creams and oil‐in‐water emulsions. A theoretical approach to the assessment of the rate of interfacial film formation is discussed in connection with emulsion stability. Finally, some speculation is made on the use of ultralow shear rate methods for the detection of polymer‐drug interactions.
RATE OF FREEZING AND INTEGRITY OF VEGETABLE TISSUES: IV: Observations on Summer Squash (Cucurbita pepo L.)
Authors: CRIVELLI G. , BUONOCORE C.
Published: February 2007

This paper reports histological observations on blanched and unblanched summer squash tunnel frozen at different rates. The detected textural damage consisted of detached cell layers, cell tearings, cavities, and various changes in the cytoplasm, nucleous, and starch granules. The number and extent of these damages increased as the freezing rate decreased. Blanching made the tissue more sensitive to freezing damage. With 5 mm thick slices, the critical freezing time is less than 15 min at ‐ 35°C.
FREEZE‐THAW DAMAGE TO PROTOPLASMIC STRUCTURE IN HIGH MOISTURE, EDIBLE PLANT TISSUES
Authors: MOHR W. P.
Published: February 2007

Abstract Three high moisture plant tissues, whose textural response to freeze‐thawing differs noticeably, were studied ultrastructurally before and after controlled freeze‐thaw regimes. Fine structural components of the protoplasm were usually disrupted extensively, although to varying degrees, depending on tissue type and freeze‐thaw conditions. Possible reasons for the apparent protection in some of the material studied are discussed. It is concluded that protoplasmic structure probably plays an insignificant role in influencing the textural properties of high moisture, frozen‐thawed plant tissues.
AN ACCURATE, LOW COST FIRMNESS MEASURING INSTRUMENT*
Authors: DIENER R. G. , SOBOTKA F. E. , WATADA A. E.
Published: February 2007

Abstract A low‐cost, automatic firmness measuring instrument was developed using commercially available components such as: dial gage, dashpot lowering mechanism, weight sets and probe tips. The details of the assembly and the names of parts manufacturers are given. The instrument is an automated modification of the original P‐L Meter developed by Parker and Levin at Michigan State University. The application of the instrument to firmness measurements on cherries and tomatoes is summarized and illustrated with typical results. Tomato studies covered the relationship between firmness and variables such as: fruit size, cultivar type, changes in protopectin content, polygalactu‐ronase and cellulase activity. The readings compared favorably with those obtained with the Instron Universal Testing machine.
RHEOLOGY AND TEXTURE OF DAIRY PRODUCTS
Authors: PRENTICE J. H.
Published: February 2007

Rheological and textural properties of milk, cream, butter and cheese are reviewed and discussed in light of available information on their structure. It is pointed out that semantic problems hindered a more organized approach to texture studies, while economical considerations prevented a general use of instrumental quality control methods.
DISPERSION STATE OF PROTEIN‐STABILIZED EMULSIONS
Authors: MITA TOMOYOSHI , IGUCHI EIKO , YAMADA KENICHI , MATSUMOTO‡ SACHIO , YONEZAWA DAIZO
Published: February 2007

The stability of concentrated benzene‐in‐water emulsions emulsified by bovine serum albumin (BSA) in the presence of various concentrations of sodium chloride has been measured in the light of the coalescence kinetics. On the acid and alkaline sides of the isoelectric point of BSA (pH 4.9), the rate of coalescence between globules decreased and approached that at the isoelectric point of BSA with increasing concentrations of sodium chloride. In these systems, the interfacial tension at the benzene/aqueous BSA solution interface, and the globule size distribution in the emulsions, reached the values observed at the isoelectric point when the concentration of sodium chloride was above about 50 mM. The role of the adsorbed film of BSA on the surface of dispersed globules is considered in relation to the dissociation state of the BSA molecules.
TEXTURE OF FRESH‐PACK WHOLE CUCUMBER PICKLES: CORRELATION OF INSTRUMENTAL AND SENSORY MEASUREMENTS*
Authors: JEON IK JOON , BREENE WILLIAM M. , MUNSON SHIRLEY T.
Published: February 2007

Correlations were determined between Texture Profile Analysis parameters of brittleness, hardness or total work of compression obtained with the Instron testing machine and sensory responses of firmness or crispness in evaluating texture of fresh‐pack processed whole cucumbers (1‐in. diam) of three ‘firm’ pickling cultivars (Explorer, Chipper, GY 3), two ‘soft’ pickling cultivars (Green F, Mincu) and a parthenocarpic slicer (MSU 6902 G). Further, correlations were determined between the TPA parameters and Magness‐Taylor fruit pressure test (FPT) firmness. TPA hardness and total work correlated well with sensory responses; FPT firmness correlated satisfactorily with sensory firmness. Mean textural values from the various methods were compared with those obtained in the same manner for raw cucumbers. TPA brittleness tended to disappear in the processed fruit. Processing reduced mean TPA values across the six varieties to 35‐58% of raw fruit values; it decreased mean FPT firmness to only 88%.
TEXTURE OF SALT STOCK WHOLE CUCUMBER PICKLES: CORRELATION OF INSTRUMENTAL AND SENSORY MEASUREMENTS*
Authors: JEON IK JOON , BREENE WILLIAM M. , MUNSON SHIRLEY T.
Published: February 2007

Correlations were determined between Texture Profile Analysis (TPA) parameters of brittleness, hardness or total work of compression obtained with the Instron testing machine and sensory responses of firmness or crispness in evaluating texture of fermented salt stock whole cucumbers (1‐in. diam) of three ‘firm’ pickling cultivars (Explorer, Chipper, GY 3), two ‘soft’ pickling cultivars (Green F, Mincu) and a partheonocarpic slicer (MSU 6902 G). Correlations were also determined between the TPA parameters and Magness‐Taylor fruit pressure test (FPT) firmness. Correlations were good between TPA parameters and FPT firmness. Correlations were poorer between instrumental and sensory methods due largely to inordinately high sensory scores assigned to salt stock of the slicer by all panelists. Mean textural values from the various methods were compared with those obtained in the same manner for raw cucumbers. TPA brittleness tended to disappear in salt stock. Processing reduced mean TPA values across the six varieties to 39‐86% of raw fruit values. Mean FPT firmness was relatively unchanged at 99% that of raw fruit. Desalting from 16% down to 8 % or 4% NaCl reduced TPA values but increased FPT firmness.
MODIFICATIONS AND APPLICATIONS TO FOODS OF THE GENERAL FOODS SENSORY TEXTURE PROFILE TECHNIQUE
Authors: CIVILLE GAIL VANCE , LISKA IRENE HENRY
Published: February 2007

The primary attributes of the General Foods sensory texture profile technique are standardization, reproducibility, and ease of correlation with instrumental measurements. Since the original publication in 1963, the method has undergone modifications and refinements such as: addition of an initial stage for evaluation of surface properties, evaluation of certain mechanical characteristics of elasticity and cohesiveness on specific products, and development of texture profile techniques and terminology for the evaluation of semi‐solids. Application of this expanded texture profile method is demonstrated using foods such as vanilla cookies, frankfurters, and whipped toppings.
APPLICATION OF THE GENERAL FOODS TEXTUROMETER TO SPECIFIC FOOD PRODUCTS
Authors: SZCZESNIAK ALINA S. , HALL BERTRAND J.
Published: February 2007

The application of the Texturometer to a variety of foods is discussed. Illustrative data are reported for puddings, whipped toppings, cold cereals, potato chips, bread at different stages of staling, frankfurters, French fried potatoes, chocolate, etc. A one‐kernel technique for rice is described and correlations with sensory evaluation for specific products are discussed. It is emphasized that optimum conditions of testing must be established for each class of products to parallel the human being who alters the manner of manipulating food in the mouth depending on its textural characteristics. Instrument conditions found adequate for testing different foods are given.
TENSILE PROPERTIES OF BEEF SEMITENDINOSUS MUSCLE AS AFFECTED BY HEATING RATE AND END POINT TEMPERATURE
Authors: PENFIELD M. P. , BARKER C. L. , MEYER B. H.
Published: February 2007

The effects of heating rate and end point temperature on tensile properties of beef semi‐tendinosus muscle were studied. Samples of meat heated in glass tubes in a water bath to simulate oven roasting at 93 °C had lower (P < 0.01) shear values than those heated to simulate oven roasting at 149 °C. Samples heated to 60 and 70°C had lower (P < 0.001) shear values than samples heated to 50°C.

Instron breaking strength values varied (P < 0.001) with end point temperature, but were not significantly affected by the rate of heating. Significant (P < 0.001) interactions between the end point temperature and heating rate, as well as between the end point temperature and fiber direction suggested that Instron breaking strength measurements may be more sensitive to changes in tenderness than Warner Bratzler shear measurements.
INSTRUMENTAL MULTIPLE TEXTURE PROFILE ANALYSIS OF COOKED GROUND BEEF PATTIES AND SMOKED BEEF
Authors: VOISEY PETER W. , LARMOND ELIZABETH
Published: February 2007

An instrumental texture profile for cooked hamburger patties was obtained by repeated tests on the same samples in the wire extrusion cell of the Ottawa Texture Measuring System. The correlation between sensory and instrumental texture profile parameters was increased when two or more instrument test cycles were applied to each sample in the same test cell. Tests with smoked beef and hamburger patties showed that the change in textural characteristics with repeated cycles depended on the texture of the food.
STUDIES ON ALBIZIA ZYGIA GUM 4.1 COMPARATIVE ASSESSMENT OF RHEOLOGICAL PROPERTIES OF ALBIZIA AND OTHER MUCILAGES
Authors: MITAL H. C. , OCRAN J. , FOKUO Y. D.
Published: February 2007

Rheological properties of albizia, tragacanth, methylcellulose and sodium carboxymethylcellulose were compared. All gums exhibited non‐Newtonian flow with thixotropy which was affected by temperature, pH, concentration of the gum and presence of electrolytes. It is concluded that 1% lbizia mucilage should have the same suspending power as 0.4% tragacanth.
RIPENING THE TIME
Authors: BLAIR G. W. SCOTT
Published: February 2007

During a period of forty years, the author and his colleagues have developed a series of Theological (as distinct from chemical) tests to replace the subjective assessments of experts in various industries. In most cases, instrumental data correlated well with subjective judgements, but (so far as is known) only in one case is the Theological instrument currently used.
VIEWS ON RELATING INSTRUMENTAL TESTS TO SENSORY ASSESSMENT OF FOOD TEXTURE. APPLICATIONS TO PRODUCT DEVELOPMENT AND IMPROVEMENT 1,2
Authors: KAPSALIS JOHN G. , MOSKOWITZ HOWARD R.
Published: February 2007

Well‐defined measurements of the mechanical properties of food and the reduction of sensory attributes to the fundamental primary entities, together with the definition of their correlation functions, provide the basis for the eventual development of instruments calibrated in terms of human sensory response and having a high probability of predicting the consumer reaction. Since mechanical measurements of most foods are time‐dependent, the understanding of conditions prevailing during sensory testing (rate of shear, etc.) will aid in selecting the optimum conditions for instrumental testing. Recent progress in this area has been made with fluids and some solid foods. The method of magnitude estimation assists the researcher in discovering the underlying laws relating physical product changes to perceived textural changes. At the same time, magnitude estimation also aids the product developer to determine empirical, ad hoc relations between physical levels of mechanical variables and textural perceptions, even if the true, underlying relationships are not known. Ad hoc equations can be used (in conjunction with optimization techniques) to determine the combination of mechanical variables that (a) produce a specific sensow texture profile, and (b) maximize texture/product acceptability.
TECHNOLOGICAL GAPS IN VEGETABLE PROTEIN TEXTURIZATION
Authors: BOYER ROBERT A.
Published: February 2007

The growth of the textured vegetable protein industry has not kept pace with early predictions. High costs and marginal quality are among the factors retarding progress. Some of the technological gaps handicapping the industry are: lack of a process for preventing formation of off‐flavors by enzymes while maintaining protein functionality, lack of a low cost thermosetting binder, lack of a protein suitable for spinning, and the indigestibility of certain soybean fractions. These problems are discussed and new texturizing techniques are pointed out which show promise of overcoming or avoiding some of these problems.
NEW METHOD FOR THE DETERMINATION OF YIELD STRESS1
Authors: DE KEE D. , TURCOTTE G. , FILDEY K. , HARRISON B.
Published: February 2007

A method is proposed for determining the yield stress of liquid and semi‐liquid foods. The described technique makes use of a modified Fisher Autotensiomat apparatus. A yield stress range of from 20 dynes/cm2 to about 900 dynes/cm2 was covered by products such as condensed milk and tomato paste, respectively. The data were compared with the results obtained with a Ferranti‐Shirley cone and plate viscometer, a Chainomatic Beckers balance and a Thomas‐Stormer viscosimeter. With the exception of the data from the latter instrument, the results were in good agreement.
SENSORY QUALITIES OF FOOD SOUNDS BASED ON INDIVIDUAL PERCEPTIONS1
Authors: VICKERS Z. M. , WASSERMAN S. S.
Published: February 2007

Sounds emitted by eighteen foods were positioned in one‐ and two‐dimensional spaces by the nonmetric multidimensional scaling (MDS) algorithm MINISSA. Each of the eighteen food sounds was also scored on 15 sensory acoustical quality attributes. These sensory quality data were then used to study and interpret the MDS graphical representation. The results suggest two basic sensory criteria for distinguishing food sounds. One of these criteria, loudness, influences the intensity of many of the other acoustical qualities. The second criterion is unevenness or discontinuity. The continuous‐discontinuous quality of a sound provides a good description of the axes for both the one‐dimensional and the two‐dimensional MDS solutions.
RHEOLOGICAL PROPERTIES AND APPLICATIONS OF MESQUITE TREE (PROSOPIS JULIFLORA) GUM 2. RHEOLOGICAL PROPERTIES AND STABILITY OF O/W EMULSIONS CONTAINING MESQUITE GUM
Authors: CARTER E. J. VERNON , SHERMAN P.
Published: February 2007

Oil‐in‐Water emulsions stabilised by mesquite gum have been examined by their creep compliance‐time response at a constant low shear stress and by shear stress‐shear rate studies. The Theological data were influenced by pH, electrolyte (NaCl, CaCl2) and aging time. Both pH and electrolyte altered the degree of compactness of the mesquite molecules adsorbed on the oil drops. Aging produced changes in the rheological properties, the general trend depending on the rate of drop coalescence and the ability of adsorbed mesquite layers on adjacent flocculated drops to interpenetrate and form new linkages. The drop coalescence rate was highest at pH 7.0, but this was offset by greater interpenetration so that the rheological parameters increased substantially during aging.
A METHOD FOR RECORDING THE AMPLITUDE OF FORCE FLUCTUATIONS DURING TEXTURE TESTS1
Authors: VOISEY PETER W. , KLOEK M. , MOHR W. P.
Published: February 2007

A means of measuring the amplitude of force fluctuations during texture tests is described. A maximum‐minimum module added to the electronic force recording system gives a direct readout of amplitude. The method has potential applications in research and quality control The technique is demonstrated with the back extrusion test applied to tomato juice. The results show that the maximum amplitude of the force fluctuations during extrusion is related to the graininess of the juice.