bluuebunny/crossref_metadata_2025 huggingface dataset:
HEAT TRANSFER to and TRANSPORT PROPERTIES of WHEAT GLUTEN IN A TUBULAR REACTOR
Authors: STRECKER T.D. , CAVALIERI R.P. , ZOLLARS R.
Published: February 2007

The design and modeling of a tubular reactor, similar to an extrusion rheometer, which accounts for reacting flow is described. A numerical study (finite differences) of heat transfer to a flowing and reacting biopolymer melt (wheat gluten), similar to extrusion processing, is described and compared to experimental data. the cylindrical wall is nonisothermal in the axial direction, but is adequately characterized by a third‐order polynomial determined experimentally. Convective and viscous dissipation terms are included in the energy equation. the rheological behavior of the melt is described by a power law model, . The consistency coefficient pre‐exponential, m0, is 530,000–2,100,000 Pa‐secn and the power law exponent or flow index, n, is 0.38–0.65 for a 25–30% moisture content range and a 110–209 C temperature range. the flow index decreases with increasing conversion due to polymerization reactions occurring at elevated temperatures. Flow curves, bulk temperatures, and temperature profiles are presented for a variety of cylinder wall temperatures and biopolymer moisture contents.
CHANGES IN the VISIBLE/NEAR‐INFRARED SPECTRA of CHICKEN CARCASSES IN STORAGE1
Authors: CHEN YUD‐REN , HUFFMAN ROY W. , PARK BOSOON
Published: February 2007

A spectrophotometer was used to measure the visible/near‐infrared (Vis/NIR) spectra of post‐mortem chicken carcasses freshly slaughtered, 1, 2, 3, 4, 8, 11, and 14 days after storage at 0, 4, and 20C. the spectrum of a carcass after storage was compared with the spectra of freshly slaughtered carcasses and the spectra of carcasses stored at the different temperatures. the method of comparison was performed by computing the Mahalanobis distance of the sample's second central difference spectrum from the group means of the second central difference spectra of all the carcasses measured shortly after slaughter (about 1 h) and the set of second central difference spectra of the carcasses stored at each temperature. the results showed the spectra of the chicken carcasses changed 24 h after removal from the slaughter plant, even though they were stored at 0C. the spectra of the carcasses stored at 20C were different from those of the carcasses stored at 0 and 4C. the spectra of the carcasses stored at 0 and 4C for the first 8 days remained in the same class of the spectra of the carcasses at 1 day of storage at 0C. However, the spectra changed dramatically after 8 days of storage. the pattern of change of the spectra coincided with that of the myoglobin and oxymyoglobin changes of chicken carcasses at various storage temperatures and durations. It was suggested that Vis/NIR spectroscopy has the potential to be used as a rapid, nondestructive method for monitoring the freshness of chicken carcasses.
A NONINVASIVE STUDY OF MILK CLEANING PROCESSES: CALCIUM PHOSPHATE REMOVAL
Authors: GRANT CHRISTINE S. , WEBB GREGORY E. , JEON YOUNG W.
Published: February 2007

High temperature, high pH milk processing results in the formation of mineral rich deposits that are > 70% mineral and < 30% protein by weight. This research investigates the removal of P32 labeled mixtures of calcium phosphate dihydrate (brushite, CaHPO4–2H2O) and hydroxyapatite (Ca5(PO4)3OH) from stainless steel tubes using a solid scintillation technique. Experiments were performed at pH values ranging from 2.86–7.82 and flow rates from 3.8–11.4 L/min. Previous cleaning models are reviewed and a mass transfer model is proposed which, when compared to the experimental results suggests that film removal is due to both dissolution and mechanical effects due to shear stress. A modified first order model is presented which incorporates the effects of the solvent flow rate and pH on decontamination rates. This first order model is in agreement with the experimental results over the range of pH and flow rates investigated.
PUNCTURE AND STRESS RELAXATION BEHAVIOR OF BLACKGRAM (PHASEOLUS MUNGO) FLOUR‐BASED PAPAD DOUGH
Authors: BHATTACHARYA SILA , NARASIMHA H.V.
Published: February 2007

Papad is a popular traditional food adjunct in South East Asian countries. The rheology of papad dough is important for the purpose of sheeting and/or rolling. In the present study, two methods for testing the behavior of papad dough (prepared from blackgram flour) have been presented and correlated with the instrumental stickiness values. These consist of an empirical method (puncture testing) and a fundamental procedure (stress relaxation characteristics). In the former method maximum stress during compression was used as an index. In the later method, the parameters determined included the stress decaying constants k1 and k2, the percent relaxation and the initial compressive stress. These tests were conducted on the papad dough with varying moisture content (32–40%) and at different dough holding (resting) times (0–120 min). Stickiness values in the range of 141 and 148° were suitable for machining of the dough to make flat circular papad sheets. The corresponding moisture content was between 35 and 36% when the holding time was in the range of 0‐30 min.
INACTIVATION KINETICS OFSALMONELLA DUBLINBY PULSED ELECTRIC FIELD
Authors: SENSOY ILKAY , ZHANG Q. HOWARD , SASTRY SUDHIR K.
Published: February 2007

Microbial inactivation kinetic models are needed to predict treatment dosage in food pasteurization processes. In this study, we determined inactivation kinetic models ofSalmonella dublinin skim milk with a co‐field flow high voltage pulsed electric field (PEF) treatment system. Electric field strength of 15–40 kV/cm, treatment time of 12–127 μs, medium temperatures of 10–50C were tested. A new inactivation kinetic model that combines the effect of treatment time to electric field strength or medium temperature was developed.
CHANGES IN ELECTRICAL CONDUCTIVITY OF SELECTED VEGETABLES DURING MULTIPLE THERMAL TREATMENTS1
Authors: WANG WEI‐CHI , SASTRY SUDHIR K.
Published: February 2007

Electrical conductivity (σ) is the most important parameter in ohmic heating. Although data exist on its changes during ohmic heating, limited information is available about preheated foods. In this study, the conductivity changes of raw vegetable samples (potato, carrot, and yam) in cyclic ohmic heating and samples preheated by conventional heating prior to ohmic heating were investigated. In cyclic ohmic heating, cylindrical vegetable samples were subjected to three repeated cycles of ohmic heating (40 V/cm, 60Hz) to 80C, and cooling to 25C. Fresh samples were also preheated by conventional heating to 80C, then subjected to ohmic heating for comparison. Specific heats changed by cycles, although moisture content remained constant in all cases. The results show that in cyclic ohmic heating, the heating rate increased by cycles. Samples preheated by either conventional or ohmic heating showed a higher heating rate than raw materials. Electrical conductivity data during ohmic heating showed that preheated vegetables have higher conductivities than fresh ones, and a tendency of increase by cycles was found.
REDUCTION OF BACTERIAL LEVELS IN FLOUR BY PULSED ELECTRIC FIELDS
Authors: KEITH WILLIAM D. , HARRIS LINDA J. , GRIFFITHS MANSEL W.
Published: February 2007

Pulsed electric fields (PEF) were tested for efficacy in bacterial reduction in dark rye flour. Field strengths greater than 20kV/cm resulted in approximately 0.6‐log reduction of aerobic plate counts. Bactericidal effect was related to field strength, pulse polarity, pulse width, and pulse number. Changing pulse period and altering gas atmosphere did not improve bactericidal effect. Reversing polarity pulses were more effective than synchronized bipolar pulses.
MILK PROTEIN/STAINLESS STEEL INTERACTION RELEVANT TO THE INITIAL STAGE OF FOULING IN THERMAL PROCESSING
Authors: KIM J.C. , LUND D.B.
Published: February 2007

Effect of temperature and surface preconditioning on β‐lactoglobulin (β‐lg) adsorption onto stainless steel have been studied using column adsorption chromatography. As temperature increased from 25 to 85C, amount of adsorbed β‐lg increased gradually and eventually reached a plateau value. Above 85C, slope of the adsorption boundary curve was significantly less than that at lower temperatures suggesting that the association constant for Langmuir adsorption isotherm increased. Conformation change caused by heat treatment also resulted in higher amount of adsorption at equilibrium (1.65 mgm−2) than native β‐lg (0.7 mgm−2) at 25C. Adsorption behavior of k‐casein was different from that of β‐lg as reflected in the shape of the adsorption curve as well as the amount of adsorption at equilibrium. A significant amount of k‐casein was adsorbed onto a β‐lg saturated surface, whereas no additional adsorption of β‐lg occurred onto a k‐casein saturated surface. These observations were in agreement with previous work. Favorable adsorption of β‐lg onto calcium phosphate‐deposited stainless steel suggests the formation of calcium phosphate/β‐lg matrix in multilayer deposit during the thermal processing of milk.
EFFECT OF PROTEIN CONTENT OF MILK ON THE STORAGE AND LOSS MODULI IN RENNETING MILK GELS
Authors: O'CALLAGHAN D.J. , O'DONNELL C.P. , PAYNE F.A.
Published: February 2007

A series of skim milks was made up with protein levels in the range 3 to 5 g/100g using ultrafiltration. The rheometric behavior during renneting was measured using low‐amplitude oscillatory shear. Gel times were determined in terms of storage modulus G′, loss modulus G″ and tan δ (=G”/G′), respectively and were modelled in terms of protein level and enzyme level. Coagulum cutting time was defined in terms of G′. A prediction equation was developed for coagulum firming time in terms of gel time and protein level. The consistency of ultimate tan δ, over the range of protein and milks, showed that G″ at coagulum cutting was related to G′ and hence an on‐line system could monitor coagulum firming rate by sensing either G′ or G′, or any related parameter, such as viscosity or complex modulus.
USING CAPACITIVE (RADIO FREQUENCY) DIELECTRIC HEATING IN FOOD PROCESSING AND PRESERVATION – A REVIEW
Authors: ZHAO YANYUN , FLUGSTAD BEN , KOLBE EDWARD , PARK JAE W. , WELLS JOHN HENRY
Published: February 2007

Capacitive (Radio Frequency) dielectric heating has great potential for achieving rapid and uniform heating patterns in foods, providing safe, high quality food products. This review describes and discusses the major technology behind capacitive (RF) dielectric heating in food processing and preservation, the current applications of the technology in the industry, the potential use of mathematical modeling for heating system design, and the major challenges facing the use of this technology in food processing. A vast amount of work is still necessary to further understand the dielectric properties of both food and packaging materials in order to refine system design and maximize performance of this technology in the field of packaged food products. Various economic studies will also play an important role in understanding the overall cost and viability of commercial application of this technology in food processing.
PHYSICAL PROPERTIES OF RECONSTITUTED CARROT/ALGINATE PARTICLES STABLE FOR ASEPTIC PROCESSING
Authors: MARCOTTE M. , TAHERIAN A.R. , RAMASWAMY H.S.
Published: February 2007

Textural and thermophysical properties of reconstituted carrot/alginate particles, subjected to thermal and mechanical stresses during aseptic processing, were investigated. Four levels of sodium alginate (4, 6, 8 and 10%) and calcium chloride (0.2, 0.5, 1.0 and 1.5%) and three levels of water addition (50, 150 and 300 mL) were used for two types of alginate (high in guluronic acid, HGA and low in guluronic acid, LGA). Hardness, water content, density and thermal conductivity of reconstituted carrot/alginate particles were determined using an Instron, an oven drying technique, a pycnometer measurement and a line heat source method, respectively. Moreover, Bacillus subtilis was inoculated in carrot/alginate particles.

Reconstituted particles, unlike carrot cubes and other vegetables, were thermally stable. The moisture content increased with a decrease in calcium chloride concentration and an increase in water addition. There was no significant effect of formulation on density and thermal conductivity measurements. Reconstituted carrot/alginate cubes were able to sustain successfully thermal and mechanical stresses encountered in a pilot scale aseptic processing system.
ON‐LINE RHEOLOGICAL CHARACTERIZATION OF PIZZA SAUCE USING TUBE VISCOMETRY
Authors: CULLEN P.J. , DUFFY A.P. , O'DONNELL C.P.
Published: February 2007

The performance of a tube process viscometer was evaluated forits ability to characterize the rheological properties of pizza sauce. Tube flow was described using common rheological models (Power Law, Herschel‐Bulkley, Casson and Bingham plastic) and model parameters were compared to laboratory rheometer data. Derived model parameters (tube) and measured pressure drop data were both correlated with other off‐line instruments, namely the Bostwick Consistometer and Brookfield viscometer. Bingham Plastic model parameters of viscosity and yield stress as generated from the tube viscometer were found to be comparable to the rheometer generated equivalents. Measured pressure drop readings using linear and Power law regression showed good predictive capability (R2 >0.99 & 0.93) of Brookfield and Bostwick Consistometer readings respectively. It can be concluded that tube viscometry would result in effective real time rheological characterization of tomato‐based products. Limitations of the Bostwick Consistometer are highlighted.
RHEOLOGICAL PROPERTIES AND FLUID DYNAMICS OF COFFEE EXTRACT
Authors: TELIS‐ROMERO JAVIER , CABRAL RENATO ALEXANDRE FERREIRA , GABAS ANA LÚCIA , TELIS VÂNIA REGINA NICOLETTI
Published: February 2007

The rheological behavior of coffee extract with different water contents (49 to 90%) was studied at a wide range of temperatures (274 to 365 K) using a concentric cylinder rheometer. The flow curves followed different models depending on the concentration and temperature level. Newtonian behavior was observed at high values of water content and temperature, changing to power law as these values were decreased. The Newtonian viscosity as well as the consistency and behavior index could be well correlated by functions simultaneously dependent on temperature and water content. The rheological parameters, together with experimental values of pressure loss in tube flow, were used to calculate friction factors. These showed to be in good agreement with those resulting from classical theoretical and empirical equations, thus confirming the reliability of the rheological measurements.
THERMAL AND RHEOLOGICAL PROPERTIES OF BRINE FROM FERMENTED AND SULFITE‐PRESERVED CUCUMBERS1
Authors: FASINA O.O. , FLEMING H.P. , MCFEETERS R.F.
Published: February 2007

Pickling cucumbers may be temporarily preserved by fermentation in brine (6–8% NaCl) or without fermentation in salt‐free, sulfite solution (300 ppm sulfite, pH 3.5). Brines obtained from preservation processes are often discarded. Due to environmental concerns, there is increasing consideration for further use of the brine solutions by recycling for use in bulk storage or filtration and incorporation into finished products. Thermal and rheological properties are fundamental to the reuse of the brine. The effect of temperature was determined on the rheological (5–45C) and thermal properties (5–75C) of brine. The properties of the brine samples were found to be significantly different (P < 0.05) from each other and from water. Salt content was the most important factor affecting the thermal and rheological properties of brine. At the same conditions, the values of the properties (thermal conductivity, specific heat, and thermal diffusivity, viscosity) were about 5 to 23% less than the corresponding values for water.
EFFECT of DRYING TYPE and DRYING CONDITIONS OVER FERMENTATIVE ABILITY of BREWER'S YEAST
Authors: LUNA‐SOLANO G. , SALGADO‐CERVANTES M.A. , RAMIREZ‐LEPE M. , GARCIA‐ALVARADO M.A. , RODRIGUEZ‐JIMENES G.C.
Published: February 2007

In this work the growth and glucose consumption as well as alcohol production kinetics of fresh and rehydrated brewer's yeast were evaluated. Dried yeast was obtained by fluidized bed and spray drying. Based on fermentation trials, there was no difference between the number of viable cells determined at the end of the stationary phase, however differences in growth velocity between the dehydrated yeast and the fresh yeast cream were found. Regarding alcohol production, no differences were found in most of the treatments (F2, F3, F4*, A1, A2. A3 and A4) with respect to the fresh yeast. the brewery dried yeast with an efficient viability and fermentative ability can be stored at least 4 months and used when required. Therefore the need of conventional propagation and fresh yeast transport may be eliminated.
COMPLEX METHOD FOR NONLINEAR CONSTRAINED MULTI‐CRITERIA (MULTI‐OBJECTIVE FUNCTION) OPTIMIZATION of THERMAL PROCESSING
Authors: ERDOǦDU FERRUH , BALABAN MURAT O.
Published: February 2007

The goal in a multi‐objective function optimization problem is to optimize the several objective functions simultaneously. the complex method is a powerful algorithm to find the optimum of a general nonlinear function within a constrained region. the objective of this study was to apply the complex method to two different shapes (a sphere and a finite cylinder) subjected to the same thermal processing boundary conditions to find a variable process temperature profile (decision variable) to maximize the volume‐average retention of thiamine. A process temperature range of 5 to 150C was used as an explicit constraint. Implicit constraints were center temperature and accumulated center lethality of the sphere and the finite cylinder. the objective functions for both shapes were combined into a single one using a weighting method. Then, the previously developed complex algorithm was applied using Lexicographic Ordering to order the objective functions with respect to their significance. the results were reported as optimum variable process temperature profiles using the given geometries and objective functions. the thiamine retentions were also compared with a constant process temperature process, and 3.0% increase was obtained in the combined objective function. the results showed that the complex method can be successfully used to predict the optimum variable process temperature profiles in multi‐criteria thermal processing problems.
MIXER VISCOMETRY to CHARACTERIZE FLUID FOODS WITH LARGE PARTICULATES
Authors: OMURA ALISON P. , STEFFE JAMES F.
Published: February 2007

Mixer viscometry is an effective means of characterizing fluids containing particulates. an interrupted helical screw impeller used to determine the flow behavior of fresh concrete was scaled‐down to analyze fluid foods with large particulates. the mixer viscometer constant was determined to be 1.6 rad−1 by the matching viscosity method. Large particulate food materials successfully investigated in this study included cream corn, salsa, smooth pasta sauce and chunky pasta sauce.

Apparent viscosity curves were constructed from torque and angular velocity data. Testing materials exhibited shear‐thinning behavior and temperature dependence. Analysis revealed K and n values ranging from 10.1 Pa sn to 40.3 Pa sn and 0.17 to 0.36, respectively. Regression control charts, based on apparent viscosity and average shear rate data were constructed for each product. A protocol is presented for producing and utilizing these charts as a statistical quality control tool for industry.
ADSORPTION CHARACTERISTICS OF FUNCTIONAL SOY PROTEIN PRODUCTS
Authors: PAN ZHONGLI
Published: February 2007

The moisture adsorption characteristics of three commercial functional soy protein products (two isolates and one concentrate) in the temperature range of 10 to 40C were studied. The temperature showed significant effect on both the change of moisture content during adsorption and equilibrium moisture content. The rate of moisture adsorption of a soy protein isolate at water activity of 0.84 increased, but its equilibrium moisture content decreased with the increase of temperature. The suitability of Peleg and GAB equations for modeling the change of moisture content during adsorption and adsorption isotherms was respectively examined, and the constants in both equations were determined. In the temperature range of 10C to 40C, the relative errors of predicted change in moisture content at water activity of 0.84 and predicted isotherms of a soy protein isolates were ranged from 1.36% to 4.85% and 2.80% to 3.63%, respectively. The two equations can be used to predict the change in moisture content during adsorption and isotherms of functional soy protein products at different temperatures with satisfactory accuracy.
NUMERICAL SIMULATION OF CONDUCTION HEATING IN CONICALLY SHAPED BODIES1
Authors: PORNCHALOEMPONG P. , BALABAN M.O. , CHAU K.V. , TEIXEIRA A.A.
Published: February 2007

A 2‐dimensional energy balance approach was used to model temperature distribution in conduction heated conically shaped bodies. A numerical solution by finite differences to the second order partial differential equation for heat conduction served as basis for the model. The cone was divided into small volume elements. The inner elements were concentric rings of rectangular cross section while those at the side surfaces had triangular cross‐sections. Energy balance equations for the volume elements were solved explicitly. Acrylic of known thermal properties was used to fabricate cones in 3 different geometries and sizes, varying from a frustum to a point cone. Every cone had 3 or 4 thermocouples (36 gauge, T type) inserted at different locations. Heat penetration tests were carried out in a water bath with constant and variable water temperatures. Experimental temperatures at different locations within the cones agreed well with temperatures predicted by the model. Use of the model to predict the location of the slowest‐heating point or “cold point” under different processing conditions was also demonstrated.
MOISTURE SORPTION CHARACTERISTICS of STARCH GELS. PART II: THERMODYNAMIC PROPERTIES
Authors: McMINN W.A.M. , AL‐MUHTASEB A.H. , MAGEE T.R.A.
Published: February 2007

A thermodynamic approach was used to interpret the experimental adsorption and desorption isotherm data for potato starch gel. Calculation of the thermodynamic properties (differential enthalpy, integral enthalpy, differential entropy and integral entropy) provides an understanding of the properties of water and energy requirements associated with the sorption behavior. Isosteric heats (differential enthalpies) were calculated through direct use of moisture isotherms by applying the Clausius‐Clapeyron equation. the differential enthalpy and entropy decreased with increasing moisture content and were adequately characterized by an exponential model. A plot of differential heat versus entropy satisfied the enthalpy‐entropy compensation theory. the spreading pressure increased with increasing water activity, and decreased with increasing temperature. the net integral enthalpy increased with moisture content to a maximum value (around the monolayer moisture content) and then decreased. In a reverse manner, the net integral entropy decreased with moisture content to a minimum value and then increased.
SOME EXPERIENCES WITH THE GENERAL FOODS TEXTUROMETER*
Authors: BRENNAN J. G. , JOWITT R. , MUGHSI O. A.
Published: February 2007

Abstract As part of a programme of investigation into the effects of processing on the texture of food the General Foods Texturometer was adopted, because it appeared to offer versatility, multiple‐property determination and a fair degree of objectivity.

Preliminary investigations with the instrument indicated a high degree of reproducibility when used on a ‘recoverable’ material (rubber). The results are highly dependent on the dimensions of the sample and reproducibility decreases somewhat with increasing hardness of material under test. The ‘representativeness’ of the results for a range of food materials varied widely, being influenced by the uniformity of the material and the accuracy with which samples can be prepared.

Experiments to correlate the results from this instrument with those from the Instron Universal Testing Machine, the Kramer Shear Press and a subjective panel method indicate that the Texturometer ‘hardness’ might prove the most useful measure of the firmness/hardness of foods as judged subjectively. None of the other textural properties measured by the Texturometer in this work proved of value in indicating subjective textural characteristics and further study of such properties is currently in progress.
TEXTURAL PROPERTIES OF DEHYDRATED FOODS. RELATIONSHIPS WITH THE THERMODYNAMICS OF WATER VAPOR SORPTION
Authors: KAPSALIS JOHN G. , DRAKE BIRGER , JOHANSSON BIRGIT
Published: February 2007

Abstract Textural properties of pre‐cooked, freeze‐dried beef and of special bite‐size space foods, all of which were designed for consumption without prior rehydration, were determined by instrumental and sensory methods at different relative humidity points of the moisture sorption isotherm. Supplemental instrumental measurements were also made on completely rehydrated pre‐cooked, freeze‐dried beef.

In general, as the relative humidity increased, the mechanical properties of hardness and cohesive‐ness (Szczesniak) increased, whereas the mechanical property called the crushability index (Drake) and the sensory property ‘ease of biting’ decreased. Close relationships were found between the heat of sorption and the sensory rating of heat evolved in the mouth during chewing of initially dry meat samples. Good correlations were also obtained between other thermodynamic functions and textural properties.
MEAT TEXTURE: I. Subjective Assessment of the Texture of Cooked Beef
Authors: HARRIES J. M. , RHODES D. N. , CHRYSTALL B. B.
Published: February 2007

69 beef roasts from different breeds, ages, growth histories and joints, were judged for texture, hot or cold, by a panel of 12 tasters. The panel was selected for discrimination and consistency over a series of training sessions during which a descriptive score sheet was developed through repeated discussion. Eight characteristics were decided upon to describe the texture of roast beef; seven on scales (resistance, wetness, juiciness, cohesiveness, hardness, overall texture, chew count) and one qualitative (adjectival descriptions).

The panel average scores for the seven quantified characteristics were subjected to factor analysis and the loss of information involved in reducing the matrices to two dimensions was 6.3% (hot tasting) and 4.6% (cold tasting). Factor scores calculated for both sets of data agreed in being highly correlated (0.98 > r > 0.90); Factor 1 with ‘resistance’, ‘cohesion’, ‘hardness’, ‘overall texture’ and ‘chew count’ and Factor 2 with ‘wetness’ and ‘juiciness’, but poorly with any characteristic in the other group (0.11 > r > 0.03). Thus, the texture of roast beef was appreciated by this panel in two characteristics describable as ‘toughness‐tenderness’ and ‘juiciness’, and the more elaborate scoring system originally devised did not add appreciably to the precision of measurement.

Comparison of factor scores on samples tasted both hot and cold showed that the relative toughness‐tenderness was maintained between samples under both conditions, whereas juiciness was not.
MODIFICATION OF FOOD CHARACTERISTICS WITH CELLULOSE HYDROCOLLOIDS II: The Modified Bingham Body ‐ A Useful Rheological Model*
Authors: ELLIOTT J. H. , GREEN C. E.
Published: February 2007

Rheological measurements were made with the Weissenberg Rheogoniometer on a series of unctuous materials including butter, margarine, an ointment, and gels prepared from sodium carboxymethylcellulose of a low degree of substitution. In steady shear, these substances show a sharply peaked stress overshoot. The stress response to an imposed sinusoidal strain is almost a square wave. These responses may be qualitatively described by a modified Bingham body consisting of a viscous element of viscosity, ν, a yield element having a yield stress of s̀0, r at rest and s̀0, s when moving (s̀0, r≥s̀0, s), and an elastic element of modulus, G, connected in series.

The response of this model for imposed steady and sinusoidal shear has been calculated in terms of the model parameters. The boundary condition equations for the imposed sinusoidal shear case cannot be solved in a closed form. Numerical solutions were obtained by computer for the full range of the parameters using a successive approximation technique. The predictions of this model are in good agreement with experimental results, and enable such results to be interpreted in terms of meaningful physical parameters.
GENERAL FOODS TEXTURE PROFILE REVISITED‐TEN YEARS PERSPECTIVE
Authors: SZCZESNIAK NA S.
Published: February 2007

The history of the development of the GF Texture Profile is traced and modifications introduced since it was first published are reported. The method is based on the recognition that texture is a multi‐dimensional attribute. While the method is widely accepted, criticisms have been made which are acknowledged and answered. The present day status with respect to applications to both sensory and instrumental measurements is briefly summarized.
TEXTURE ANALYSIS OF TEXTURED SOY PROTEIN PRODUCTS: RELATIONS BETWEEN INSTRUMENTAL AND SENSORY EVALUATION*
Authors: LOH JIMBAY , BREENE W.M.
Published: February 2007

The Minnesota Texture Method, designed to differentiate objectively textural differences in commercial textured soy protein (TSP) products and their mixtures with ground beef, was correlated statistically with sensory evaluation. The results indicated substantial predictability of sensory evaluations from MTM on eight selected commercial TSP products and their mixtures with ground beef.
PSYCHORHEOLOGY ‐ ITS FOUNDATIONS AND CURRENT OUTLOOK1
Authors: MOSKOWITZ HOWARD R.
Published: February 2007

Psychorheology is the study of how we perceive the textural charac‐teristics of materials. This paper concerns three streams of research on psychorheology: psychological inputs, food science approaches, and models as developed by physicists. The approaches of the three sciences are described from an historical perspective, and the gradual inter‐twining of the sciences in psychorheology is explored to assess prospects for future research.
FORCE‐DEFORMATION AND TEXTURE PROFILE BEHAVIOUR OF AQUEOUS SUGAR GLASSES
Authors: McNULTY P. B. , FLYNN D. G.
Published: February 2007

Aqueous sugar glasses, simulating the structure of commercial boiled sweets, were investigated in their temperature transition range by force deformation and texture profile tests using the Instron Universal Testing Machine. Cylindrically cast and thermally equilibrated aqueous glucose‐sucrose model systems having 2—2.3% moisture (w/w) and containing glucose to sucrose ratios (%w/w) of 100/0, 70/30, 55/45 and 35/65 were used. Force‐deformation tests revealed that the Young's modulus was independent of the glucose‐sucrose ratio and decreased drastically with temperature from 820 MN/m2 at 3°C to 30MJV/m2 at 30°C.

Texture profile tests were carried out on a model system (35/65 glucose‐sucrose blend) and on a commercial hard boiled sweet. Experimental profiles for both systems were largely similar and permitted evaluation of the textural parameters of hardness and cohesiveness. Composite force‐strain or force‐penetration curves were constructed from series profile tests on the same sample and demonstrated that (a) high values of hardness were found with a flat probe and low temperatures; (b) low values of hardness were found with cone and wedge probes and high temperatures. Cohesiveness generally decreased as the initial applied strain increased, because higher strains resulted in greater sample fracture and/or plastic flow. On the other hand, temperature and probe type had little effect on cohesiveness.

The difficulties experienced in bridging the gap between the empirical and the fundamental approaches to texture profiling of food are discussed.
RHEOLOGICAL ASPECTS OF THE RENNETING OF MILK CONCENTRATED BY ULTRAFILTRATION
Authors: CULIOLI J. , SHERMAN P.
Published: February 2007

The kinetics of clotting by rennet of ultrafiltrated milk were studied by determining induction and clotting times, and development of the rigidity modulus as a function of rennet concentration and protein content in the sample. Creep cmpliance‐time studies were conducted on the resultant gels at three different stresses. Clotting time increased with protein content and decreased with rennet concentration. The protein effect on clotting time decreased with increasing rennet concentration and was practically nil at 200 mg enzyme/kg sample. The ultimate rigidity and the viscoelastic parameters of gels depended on the protein concentration in a double logarithmic relationship. The calculated values of the constants indicated that the viscosities were influenced to a greater degree by the protein concentration than were the elastic moduli. The renneted milk gels exhibited creep compliance‐time response at low shear stresses indicative of the viscoelastic behaviour of an interlinked three‐dimensional network. Gelation followed a second order reaction in its initial stages and an approximately third order reaction in the final stage. The results are discussed in terms of potential mechanism and type of bonds involved.
FACTORS AFFECTING TENSILE AND WARNER‐BRATZLER SHEAR VALUES OF RAW AND COOKED MEAT
Authors: BOUTON P. E. , HARRIS P. V.
Published: February 2007

The influence of slit width on the force deformation curves obtained for raw and cooked meat of different myofibrillar contraction states was investigated with a modified version of the Warner‐Bratzler (WB) shear device. Decreasing the clearance or compressing the sample directly onto a base plate (i.e. no slit) had little effect on the initial yield force values. Meat samples retained most of their original tensile strength after compression to initial yield on the shear device. Even cold‐shortened cooked samples compressed to peak force values retained over 30% of their original tensile strength.

Peak tensile and peak WB shear force measurements were highly correlated: R2= 0.71, 0.94 and 0.88 for raw, stretched/cooked and contracted/cooked samples, respectively. The slopes (WB on tensile) of the regression lines were increased by both cooking and by contraction to below rest length. These results indicate that components other than tensile in the WB shear force measurements were increased by cooking and by myofibrillar contraction.
TEXTURIZATION THROUGH SPINNING
Authors: HARTMAN WARREN E.
Published: February 2007

Principles of spinning edible protein fibers are discussed and the commercial development of the process is traced. Basic considerations involve structure requirements for a polymer to be fiber‐forming and the control of processing steps. Physical phenomena occurring during the spinning process are enumerated as well as structural changes, the exhibited physical properties and principle process variables. Recent modifications of the spinning process include melt‐spinning and the use of radio frequency or microwave heating for bringing the spinning solution up to the optimum forming temperature.
DIFFERENCES IN FUNCTIONAL PROPERTIES OF 7S AND 11S SOYBEAN PROTEINS
Authors: SAIO KYOKO , WATANABE TOKUJI
Published: February 2007

This paper summarizes the work done by the authors (most of it published in Japan) and other researchers. The 11S protein is different from the 7S protein in that it makes much harder Tofu gels which are more sensitive to the softening effect of phytic acid and in which the S—S bonds appear to predominate. The US protein precipitates faster and forms larger aggregates. Its gelation characteristics suggest suitability as fish and meat extender. 11S gels have a higher water holding capacity than 7S gels, higher tensile values, higher hardness and expand more on heating. Similarly, 11S films are more elastic and have higher tensile values. It is pointed out that the functional properties of proteins may be controlled by regulating the binding forces through pH and additives.
TEXTURIZATION OF SOY PROTEIN: SCIENTIFIC GAPS
Authors: DRAKE BIRGER , ANDERSSON YNGVE
Published: February 2007

Scientific gaps in texturization of soy protein are discussed against the background of philosophical questions on acceptance, quality and properties. It is concluded that science and technology are intimately linked and that the distinction between technological and scientific gaps is more practical than logical.
CONSUMER PREFERENCE AND PROPERTIES OF RAW AND COOKED MILLED RICE
Authors: MUNDO ANGELITA M. DEL , JULIANO BIENVENIDO O.
Published: February 2007

Consumer preference tests for raw and cooked rices were run on representative consumers 16 years and older in a selected Philippine village. For four sets of samples, major criteria for selecting raw milled rice were grain whiteness and hardness, and aroma and flavor for boiled rice. Actual preference ranks suggested partiality to white raw rice and low‐amylose, intermediate‐amylose and high‐amylose boiled rice in order of decreasing preference. Soft texture due to low amylose content probably contributed to better flavor of boiled rice.

Selection criteria for one set of waxy rices were aroma and whole, big grains for raw rice, and aroma and cohesiveness for rice cake suman sa antala. Properties disliked in suman were flakiness, and coarse, hard, and soft textures. Among five low‐gelatinization temperature, waxy milled rices, the traditional, aromatic, coarse‐grained Malagkit Sungsong was preferred over newer rices with less aroma and with longer grains in both raw and suman forms.
INFLUENCE OF SALTING OF RECONSTITUTED MILK ON CURDLING BY RENNET
Authors: RAMET J.P. , EL‐MAYDA E. , WEBER F.
Published: February 2007

The addition of sodium chloride to milk is traditionally used in some areas to prevent microbial and enzymatic spoilage. The effects of salting on the rheological properties of curd have been studied. An increase of the salt content from 0% to 5% induced a progressive decrease of the pH from 6.65 to 6.40 and of the luminosity from 78.23 to 75.68. Clotting and hardening times increased by up to 300%. When pH was adjusted with sodium hydroxide to 6.50 after adding salt and before adding rennet, times were increased by more than 600%.
FABRICATED FOODSTUFFS AS MULTICOMPONENT GELS
Authors: TOLSTOGUZOV V. B. , BRAUDO E. E.
Published: February 2007

A discussion is made of the physico‐chemical problems arising in the development of production methods for fabricated foodstuffs representing, as a rule, multicomponent gels. Attention is paid to the significance of irreversible phenomena during gelation. Consideration is given to the requirements for the gelling agents in the production of artificial foodstuffs. Examples are presented of the effect of fillers on gel properties.
ORAL PERCEPTION OF VISCOSITY IN FLUID FOODS AND MODEL SYSTEMS
Authors: CUTLER A. NORMAN , MORRIS EDWIN R. , TAYLOR L. JOHN
Published: February 2007

The perceived in‐mouth thickness (T) of a range of fluid foods and model systems was assessed by a trained sensory panel, using a ratio scaling technique, and correlated with objective measurements of viscosity (ηN). For Newtonian samples a simple linear correlation (r2= 0.98) is observed between log T and log η with exponent η= 0.22. The linear relationship between log T and log η for Newtonian materials was used to calculate the equivalent Newtonian viscosity (ηN) from subjective panel scores for the non‐Newtonian samples studied. The shear rate at which observed viscosity is equal to ηN decreases with ηN, as reported previously by Shama and Sherman, but also decreases with increasing shear‐rate dependence of viscosity. This implies oral perception of viscosity over a range of shear rates. Comparison of flow curves for samples assigned similar thickness scores, but showing very different shear thinning behaviour, suggests that the perceived thickness of extremely shear‐thinning materials is dominated by their high viscosity at low rates of shear. As a simple practical index, viscosity at 10 s−1 shows a better correlation (r2= 0.95) with the perceived thickness of the samples studied than values calculated by the methods suggested by Wood, or by Shama and Sherman (r2= 0.90 in both cases). The close agreement between panel scores for perceived thickness and perceived stickiness previously observed for concentrated solutions of random coil polysaccharides does not apply for several of the food systems studied, or for very concentrated solutions of xanthan.
COMPARISON BETWEEN QUANTITATIVE DESCRIPTIVE ANALYSIS AND PHYSICAL MEASUREMENTS OF GEL SYSTEMS AND EVALUATION OF THE SENSORIAL METHOD *
Authors: DAGET N. , COLLYER S.
Published: February 2007

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TEXTURE PROFILE PARAMETERS OF COOKED FRANKFURTER EMULSIONS AS INFLUENCED BY COOKING TREATMENT2
Authors: SINGH Y. , BLAISDELL J.L. , HERUM F.L. , STEVENS K. , CAHILL V.
Published: February 2007

Texture profile parameters of frankfurters were found to be generally related to cooking temperatures, except for degree of elasticity, hysteresis loss, and work ratio. Cohesiveness, elasticity, gumminess, and chewiness all were polynomial functions of cooking temperature and were smallest at 70‐75° C where physico‐chemical changes in proteins important to texture development appeared to be occurring. Hardness, compression energy of first bite, brittleness, apparent moduli of elasticity, stress at 20% compression and strain energy of compression per unit volume were all linearly related to the cooking temperature. Texture profile parameters were higher for samples with higher protein and lower moisture contents at all cooking temperatures.
RHEOLOGICAL TECHNIQUES TO EVALUATE THE SHELF‐STABILITY OF STARCH‐THICKENED, STRAINED APRICOTS2
Authors: STEFFE JAMES F. , FORD EUGENE W.
Published: February 2007

The rheological behavior of strained apricots thickened with modified tapioca starch was investigated using mixer viscometry techniques. Initially, the sample showed irreversible thixotropy which was quantified by evaluating time‐dependent torque decay. Mechanically degraded samples had time‐independent properties and were evaluated as power‐law fluids. Rheological techniques developed were successfully used to evaluate the textural shelf‐life of strained apricots thickened with different types of modified tapioca starch.
SENSORY AND OBJECTIVE EVALUATION OF A RESTRUCTURED BEEF PRODUCT
Authors: BERNAL W. V. W. , BERNAL V. M. , GULLETT E. A. , STANLEY D. W.
Published: February 2007

A study was undertaken to determine the effect of connective tissue, flake size and NaCl level on the texture of restructured beef steakettes; to examine the effect of these factors on the acceptability of restructured steakettes; and to develop sensory and instrumental texture profiles of the product. Restructured beef steakettes were manufactured with two levels of connective tissue (high, low), three flake sizes (3 mm, 6 mm, 13 mm) and three NaCl levels (0.25%, 0.50%, 0.75%). The textural attributes of these products were measured by a trained sensory panel and by objective measures of compression texture profile analysis, Warner‐Bratzler shear and three tensile tests. Most sensory texture attributes could be predicted accurately using instrumental methods. Reduction of the sensory attributes by Principal Components Analysis revealed two underlying dimensions of connective tissue and bind strength. A consumer panel rated steakettes manufactured with 6 mm flakes and 0. 75% NaCl at either connective tissue level to be the most acceptable of the 18 products manufactured for this study.
INSTRUMENTAL TEXTURE STUDIES ON CHOCOLATE IV: COMPARISON BETWEEN INSTRUMENTAL AND SENSORY TEXTURE STUDIES
Authors: MARKOV E. , TSCHEUSCHNER H.‐D.
Published: February 2007

Texture characteristics of solidified plain chocolate and milk chocolate were determined in instrumental and sensory studies. The instrumental parameters included compression strength, melting properties, maximum tensile force during hesion testing and the maximum size of dispersed solid components. To classify the sensory texture impressions into intensity ranges, by using appropriate samples, a reference scale was derived allowing a sensory panel to assign unknown chocolate samples to the respective intensity ranges. Instrumental control of the reference samples ensures satisfactory relations between instrumental and sensory data.
EFFECTS OF SALT REDUCTION ON THE RHEOLOGICAL AND GELATION PROPERTIES OF WHITE AND DARK POULTRY MEAT BATTERS
Authors: MITTAL G. S. , BARBUT S.
Published: February 2007

The rheological and gelation properties of poultry dark and white meat batters prepared with average and reduced NaCl levels (2%, 1% and 0%) and with 0.5% hexametaphosphate (HMP) added to the 1% salt batters were studied. Lowering the salt content decreased the shear stress in both the white and dark meat at the same shear rates. HMP addition to the 1% NaCl treatments increased the shear stress in the dark meat but not in the white meat at the same shear rates using a concentric cylinder viscometer. The relationship between the rotor angular velocity and shear stress of the raw batters was nonlinear and resembled a pseudoplastic behaviour with yield stress in all cases. Plots of the modulus of rigidity (G) versus cooking temperature indicated that white meat always exhibited higher G than that of dark meat. The highest G was observed in the white meat with 2.0% NaCl and the lowest in the dark meat with no salt. The batters with no salt also exhibited gel formation, however with lower G values.
STRUCTURE AND RHEOLOGICAL FUNCTION OF SIDE BRANCHES OF CARBOHYDRATE POLYMERS
Authors: HWANG JAEKWAN , KOKINI JOZEF L.
Published: February 2007

This review consists of two major parts: (1) the rheological theories of branched polymers and (2) the structural features of side branches of carbohydrates and their effects on the rheological properties. The rheological properties influenced by branching are discussed in terms of radius of gyration, intrinsic viscosity, zero‐shear viscosity (ηo), elastic properties represented by the zero‐shear recoverable compliance (Jeo), shear rate dependence of viscosity, extensional viscosity and thermal sensitivity of viscosity. The second part is focused on the structural characteristics of side branches found in four typical branched carbohydrates, i.e., starch (amylopectin), galactomannan, xanthan and pectin, with an emphasis on their contribution to the rheological properties.
COMPARISON OF TWO TYPES OF MODELS FOR CONCAVE FORCE‐DEFORMATION CURVES PRESENTATION1
Authors: SWYNGEDAU S. , NORMAND M. D. , PELEG M.
Published: February 2007

Compressive force‐deformation curves of solid foods with upward and downward concavities are described by a power law and two, two‐parameter mathematical models that can be transformed into linear equations by rearrangement. The fit of the latter to experimental data was comparable to or better than that of a two‐parameter power law model. These two models can simplify the procedure and shorten the time of data processing in certain applications of computer interfaced testing machines. Their main advantage over the power law model, however, is that they can facilitate the analysis of the compressive behavior of double‐layered arrays of objects in general and that of finger(s)‐food system in particular.
RHEOLOGICAL BEHAVIOR OF TOMATO PASTES IN STEADY AND DYNAMIC SHEAR
Authors: RAO M.A. , COOLEY H.J.
Published: February 2007

Tomato pastes (26–30 °Brix) at 40C were highly shear thinning fluids (n = 0.28) with large magnitudes of Casson yield stresses (78–212 Pa). Dynamic shear data revealed weak gel‐like behavior of the pastes: magnitudes of G′ were higher than those of G″, and both increased with oscillatory frequencies. The Cox‐Merz rule was not applicable to the steady and dynamic shear data on the pastes, but the two types of data conformed with the use of shift factor on frequency. Solids and liquid fractions in the pastes were satisfactory for correlating the dynamic properties, consistency index, and Casson yield stress.