bluuebunny/crossref_metadata_2025 huggingface dataset:
CONCENTRATION OF ONION JUICE VOLATILES BY REVERSE OSMOSIS AND ITS EFFECTS ON SUPERCRITICAL CO2 EXTRACTION
Authors: NUSS JEFFREY S. , GUYER DANIEL E. , GAGE DOUGLAS A.
Published: February 2007

Supercritical carbon dioxide extraction of onion oil at moderate temperatures produces aproduct which is characteristic of the fresh flavor of onions. It was attempted to improve extraction efficiency by concentrating the onion juice by reverse osmosis prior to supercritical CO2 extraction. Reverse osmosis was carried out for all combinations of 600, 700, and 800 psi feed pressure and 25 and 35C. The juice was concentrated to 18 oBtix and then subjected to supercritical CO2 extraction. The effect of concentration on the extraction process was evaluated by comparing the yields of extracts from concentrated juice with that of single strength juice. Concentration of onion juice by reverse osmosis improved the efficiency of supercritical CO2 extraction of onion oil and did not alter its characteristic fresh aroma.
A NEW TECHNIQUE FOR EVALUATING FLUID‐TO‐PARTICLE HEAT TRANSFER COEFFICIENTS UNDER TUBE‐FLOW CONDITIONS INVOLVING PARTICLE OSCILLATORY MOTION
Authors: ZAREIFARD M.R. , RAMASWAMY H.S.
Published: February 2007

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

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

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

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

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

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

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

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

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

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

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

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

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

Control of food processes involving vapor compression cycles as actuators is often a difficult task: indeed this particular device is itself a complex process including coupled unit operations as evaporation, compression, condensation and expansion. Nevertheless, an accurate control of heat transfer rate is often essential for global quality of product and stability of flow in exchangers.

Moreover a number of vapor compression systems are already equipped with variable speed‐compressors and fans. However, due to lack of knowledge about the dynamic behavior of these systems, the industry has not taken full advantage of these variable devices to get substantial control performance improvement.

This paper presents a lumped‐parameter model for describing the dynamics of vapor compression cycles. Based on moving‐boundary approach for the description of two‐phase/single phase interface inside the heat exchangers, this low‐order model composed of only ordinary differential equations can be highly useful for design of control strategies. This model has been validated on an experimental device and a good agreement between measurements and computed data has been found. Use of this model in food process control design is discussed.
DIELECTRIC PROPERTIES of STARCH SOLUTIONS AS INFLUENCED BY TEMPERATURE, CONCENTRATION, FREQUENCY and SALT
Authors: PIYASENA P. , RAMASWAMY H.S. , AWUAH G.B. , DEFELICE C.
Published: February 2007

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

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

Supercritical fluid extraction, with ethanol‐modified carbon dioxide, of free quercetin from onion skins (red and yellow varieties) was studied. Static mode was investigated as an extraction method, which generated a total of 0.024 g of free quercetin per kg of onion skin for the red variety, and 0.020 g per kg for the yellow variety, at 5700 psi, 40C, an average of 7.6% (molar concentration) of ethanol, and in an extraction period of 2.5 h.

The modifier was found to have an important influence on free quercetin recovery. the greater the amount of ethanol collected in the trap, the greater the amount of free quercetin recovered.

Identification and quantification analysis were conducted in a High Performance Liquid Chromatography system.
WATER ABSORPTION, LEACHING and COLOR CHANGES DURING the SOAKING FOR PRODUCTION of SOY‐BULGUR
Authors: BAYRAM MUSTAFA , KAYA AHMET , ÖNER MEHMET DURDU
Published: February 2007

In this study, the soaking process, which is the first step of soy‐bulgur production to develop a new type food product, was investigated. the soaking operation was conducted at 30, 50 and 70C for 120 min and samples were taken from the soybean and soaking water at 10 min intervals. Moisture content and color (L, a, b and YI values) of soybean were measured, as well as soluble solids content and color (L, a, b and YI values) of soaking water during the soaking process. the results were analyzed by using ANOVA and Duncan test.

Soaking time and temperature were significantly effective (P < 0.05) on all variables, except the time effect on the YI‐value.

During the soaking, moisture content, lightness (L) and yellowness (b) increased and, redness (a) and yellowness index (YI) of soybean decreased. Soluble solids content, yellowness and yellowness index increased in contrast to a decrease in the lightness and greenness of the soaking water.

As a result, soluble solids content in the soaking water increased, which illustrated the leaching of soluble solids from soybean to water. Color of soybean turned to lights, in contrast to darkening and opaqueness of water during soaking. Results showed that the moisture content, soluble solid content, L, a, b and YI values can be successfully modeled using polynomial equations, which can be used to estimate their changes during the soaking operation.
OBSERVATIONS ON STRAWBERRY TEXTURE A THREE‐PRONGED APPROACH
Authors: SZCZESNIAK ALINA S. , SMITH BERTHA J.
Published: February 2007

Sensory, instrumental and microscopic methods of evaluation were combined to permit relating textural parameters to structural characteristics of fresh, frozen and rehydrated freeze‐dried strawberries. Large cells and thin cell walls appear to account for the ease of textural damage. Degradation of cell walls, cell rupture and plasmolysis caused by senescence or processing are responsible for softening, loss of crispness and easy juice release. A good agreement was obtained between the three methods of texture evaluation.
RELATIONSHIPS OF HISTOLOGICAL STRUCTURE TO TEXTURE OF FRESH AND PROCESSED FRUITS AND VEGETABLES
Authors: REEVE R. M.
Published: February 2007

Abstract This review concerns both the botanical and the practical aspects of commonly recognized texture qualities of fruits and vegetables. Interrelationships between tissue structure and composition provide a wide variety of textural qualities in fresh and processed fruits and vegetables. Structural sources of textural appearance are described for several fruits and vegetables. Various examples of specialized supporting and fibrous tissues are also described with reference to problems of texture quality in frozen and dehydrated products. The roles of plant cell wall composition and of cellular contents, such as starch, are discussed with specific examples of manipulative control of texture in several processed products.
MEASUREMENT OF TOMATO FIRMNESS WITH A UNIVERSAL TESTING MACHINE
Authors: HOLT C. B.
Published: February 2007

A technique of punch‐testing tomatoes to measure the firmness of the different anatomical parts has been developed. A plunger with a 0.040 inch diameter tip tapering to a 0.020 inch diameter shaft is attached to the crosshead of an Instron Universal Testing Machine and driven into the tomato at a speed of 1 cm/min. Distinct peaks are observed on the force‐displacement trace which are related to the firmness of the various parts of the structure. The method can be used to follow changes in firmness during ripening, to detect ripening abnormalities, to measure differences between varieties and to detect variations in firmness over the surface of individual tomatoes.
THE THEORY AND TECHNIQUE FOR MEASURING THE FIRMNESS OF A WHOLE LOAF BY GASEOUS COMPRESSION
Authors: WILLHOFT E. M. A.
Published: February 2007

Abstract A novel technique is described for measuring the resistance to deformation of a soft body. It is suitable for measuring the bulk compression modulus of wrapped whole loaves, cakes, rubber sponges, etc., and is based on measurement of the volume of deformation resulting from the application of a known gas pressure to the outside surface of the body. Typical results are presented, including the empirical firming equation which describes the firming curve for well‐wrapped whole loaves.
ESTIMATION OF THE RATE OF SHEAR ENCOUNTERED IN TOPICAL APPLICATION OF COSMETICS
Authors: MITSUI TAKEO , MOROSAWA KEIJI , ÖTAKE CHIYOKO
Published: February 2007

Abstract The rates of shear encountered in topical application of cosmetic creams and lipstick were obtained by dividing the application velocities, at which the samples are being sheared, by the applied thicknesses of the layer. The application velocity was measured by means of a high‐speed camera. Beauty artists, formulating chemists of cosmetics and women employees were used as the sensory panel. For topical application of creams in make‐up, the maximum rates of shear were found to be between 104 and 105 S‐1, though the rate of shear differed from one kind of cream to another. The maximum rates of shear for lipstick in make‐up were smaller than those for creams and were between 103 and 104 s‐1.
CONSUMER AWARENESS OF AND ATTITUDES TO FOOD TEXTURE II. Children and Teenagers
Authors: SZCZESNIAK ALINA S.
Published: February 2007

A discussion of children’s and teenagers’ attitudes to food texture is presented based on published data relative to growth and development and on information obtained from original consumer interviews. It is pointed out that, in this population group, physiological factors appear to be dominant in shaping attitudes to texture. These are modified by psychological, social, cultural, and other factors in the adult consumer. With both children and teenagers, texture is an important attribute of foods influencing their likes and dislikes. In the young child, attitudes to food texture follow the developmental sequence of oral functions, and textures are rejected which are difficult to manipulate in the mouth at a particular stage of physical development. The high degree of texture awareness of teenagers may possibly surpass that of adults. Teenagers also appear to have a better understanding of the concept of texture suggesting that this attribute may assume greater importance with the oncoming generation of adult consumers.
IDENTIFICATION OF STIMULI CONTROLLING THE SENSORY EVALUATION OF VISCOSITY II. Oral Methods
Authors: SHAMA F. , SHERMAN P.
Published: February 2007

The stimulus associated with oral evaluation of the viscosity of liquid and viscous foods appears to embrace a range of shear rates extending from 10‐1 to 1000 s‐1. The value associated with a particular food depends on its flow characteristics. For liquid foods the stimulus appears to be the shear rate developed at an approximately constant shear stress (∼ 100 dyn cm‐2), whereas for viscous foods it appears to be the shear stress developed at an approximately constant shear rate (∼ 10 s‐1). Additional factors may be involved when evaluating highly viscous non‐Newtonian foods or foods with an oil continuous medium. These are ‘plug flow’ or the spreading coefficient, respectively.
EVALUATION OF SOME TEXTURAL PROPERTIES OF FOODS WITH THE INSTRON UNIVERSAL TESTING MACHINE
Authors: SHAMA F. , SHERMAN P.
Published: February 2007

Abstract. Analysis of published chewing force patterns indicates that the ‘first bite’ involves an approximately linear application of force. The Instron Universal Testing Machine also offers a linear pattern of force application making it possible to obtain information about textural properties identified during the ‘first bite’ from force‐compression tests. However, the data obtained in such tests are influenced not only by the applied force but also by the rate at which it is applied. Both variables must be taken into account when analysing the data, since the applied force in chewing and also the rate of force application depend on the textural characteristics of the food being evaluated. Based on a correlation of sensory responses with instrumental force‐compression‐rate of force application data, a procedure is described for establishing the mechanical force conditions that should be used in Instron tests so that they simulate those associated with the sensory evaluation.
A MECHANICAL MODEL FOR POST‐MORTEM STRIATED MUSCLE
Authors: STONER DAVID L. , HAUGH C. GENE , FORREST JOHN C. , SWEAT VINCENT E.
Published: February 2007

Abstract. A mechanical model for post‐mortem striated muscle is proposed. It is based on a combination of a 4‐element viscoelastic model with either the Voigt or the Maxwell muscle models. Its applicability was verified by making stress relaxation tests on quadricep muscles from white male rats. The tests were conducted on an Instron Universal Testing Machine equipped with an environmental chamber allowing the specimen to be submerged in Krebs‐Ringer solution and maintained at a constant temperature of 38°C.
PSYCHORHEOLOGY: LINKS BETWEEN THE PAST AND THE PRESENT*
Authors: BLAIR G. W. SCOTT
Published: February 2007

A brief discussion is given concerning the validity of psychophysics as a science with special reference to psychorheology. Some early work on psychorheology concerned mainly with cutaneous and kinaesthetic sensations is discussed. A distinction is made between connotative and denotative concepts; difficulties in defining the latter are stressed, with special reference to translating into other languages.

Denotative concepts are to be regarded as processes rather than as properties; i.e., properties changing with time often as a result of the testing. It was suggested long ago that these time‐differentials should be fractional, and it is proposed that ‐ in spite of mathematical difficulties ‐ fractional differential equations might serve as a useful adjunct to the ‘consistency profiling’ now in wide use.
THE EFFECTS OF STORAGE TIME AND TEMPERATURE ON THE BRUISING OF JONATHAN, DELICIOUS AND GRANNY SMITH APPLES
Authors: SCHOORL D. , HOLT J. E.
Published: February 2007

The resistance to bruising of Jonathan, Delicious and Granny Smith apples decreased with increasing storage time during the 1975 and 1976 seasons. Impact bruise volumes were approximately equal for the three varieties in April. Subsequent testing in June, August and October showed that bruise volumes increased markedly for both Jonathan and Delicious apples and by a small amount for Granny Smith apples. Jonathan apples deteriorated most rapidly and had broken down by October. The resistance to bruising of the three varieties was unaffected by pulp temperature over the range 2°C—30°C. Jonathan, Delicious and Granny Smith apples exhibited strong linear correlations between bruise volume and energy absorbed for all storage times, thus confirming earlier results for Granny Smith apples.
USE OF POISSON'S RATIO FOR OBJECTIVE‐SUBJECTIVE TEXTURE CORRELATIONS IN BEEF. AN APPARATUS FOR OBTAINING THE REQUIRED DATA1
Authors: SEGARS RONALD A. , HAMEL ROGER G. , KAPSALIS JOHN G.
Published: February 2007

A device is described for measuring the transverse deformation of cylindrical samples during axial compression. The device is fitted to an Instron Universal Testing Instrument and requires only standard Instron electronics and data recording systems. Calculations showing that the transverse deflection gives a good estimate of Poisson's ratio are valid for both isotropic and anisotropic materials.

Correlation coefficients for magnitude estimates of three sensory texture attributes in beef increase from 0.5 to 0.9 when Poisson's ratio is substituted for the uniaxial “modulus of elasticity.” This indicates that Poisson's ratio may be a very promising objective parameter for predicting the sensory texture quality in meat.
COMPUTER‐ASSISTED READOUT OF DATA FROM TEXTURE PROFILE ANALYSIS CURVES1
Authors: BOURNE M. C. , KENNY J. F. , BARNARD J.
Published: February 2007

The speed of computer readout plus the flexibility of interpretation of the various features of the Texture Profile Analysis (TPA) curves by an experienced operator was accomplished by placing the Instron re‐ corder charts ouer a digitizer interfaced to a computer. The digitizer provides a 14″× 14″ digitizing area with a resolution of 100 lines per inch. The operator guides a cursor over the TPA curve and the com‐ puter records X and Y coordinates in units of 0.01 in. A trigger on the cursor allows the operator to select designated foxes, distances and areas to be used by the computer in subsequent calculations of TPA parameters. Correlation coefficients between manually measured TPA parameters and computer‐assisted readout of the same force‐distance curues using apples, carrots, cream cheese, frankfurters and pretzel sticks were generally higher than r = 0.99.
RELATIONSHIP BETWEEN VISCOSITY AND FAT CONTENT OF MILK AND CREAM
Authors: VAN VLIET T. , WALSTRA P.
Published: February 2007

A comparison of the published data on the flow behaviour of milk and cream at higher shear rates reveals conflicting results which can be explained partly by differences in experimental conditions. Among others, cold agglutination and churning effects appear to play a role. In the absence of these effects and at not very low shear rates, milk behaves as a Newtonian liquid. Excellent agreement is obtained between measured viscosity (η) as a function of fat content (øf) and theoretical relations between η; and the volume fraction of dispersed particles, but only if the volume occupied by the protein particles and sugar molecules in the milk is taken into account.
BRUISE RESISTANCE MEASUREMENTS IN APPLES
Authors: SCHOORL D. , HOLT J. E.
Published: February 2007

A quick and easy method of measuring the bruise resistance of apples is described. The method is based on the strong linear correlation between energy absorbed and bruise volume from which is calculated a bruise resistance coefficient, with units ml joule−1. The bruise resistance coefficient can be accurately determined by dropping a sample of 10 apples. For each drop the energy absorbed is calculated from measured drop height, rebound height and apple mass. The bruise volume on each apple is calculated from measured apple diameter, bruise diameter and bruise depth. The bruise resistance coefficient is effective in the evaluation of packaging, handling and distribution systems for apples.
WHEY PROTEIN DENATURATION OF UHT PROCESSED MILK AND ITS EFFECT ON RHEOLOGY OF YOGURT
Authors: LABROPOULOS A. E. , PALMER J. K. , LOPEZ A.
Published: February 2007

The denaturation of whey proteins in whole milk during processing by the indirect UHT and vat systems was determined. Whey protein denaturation plateaued at about 88% following a UHT heat treatment of 149°C for 10 s. However, it reached about 88% with a vat heat treatment of 82°C for 5 min and reached 95 to nearly 100% after 10 to 15 min. Vat processing under pasteurizing conditions at 63°C for 30 min resulted in less than 10% denaturation. The yogurts prepared from the vat processed milk had considerably higher structural firmness than those prepared from the UHT milk, as confirmed by the lower value of curd firmness and the higher shear stress of these yogurts. It was also found that the structural or curd firmness of yogurts prepared from UHT milk was highest when the milk was processed for 3.3 s process holding time and was lower when the milk was processed for longer or shorter process holding times. The results suggest that the vat process at 63°C or 82°C brings about a specific change in the whey protein which leads to formation of a firm structure. This change apparently does not occur during the brief UHT treatment.
TIME‐COURSE OF VISCOSITY, SWEETNESS AND FLAVOR IN CHOCOLATE DESSERTS
Authors: PANGBORN R. M. , KOYASAKO A.
Published: February 2007

Using a strip‐chart recorder to monitor time, intensities of oral viscosity, sweetness, and chocolate flavor were evaluated for two chocolate desserts — canned pudding and a canned crème — identical in formula except for the thickening agent. The time‐intensity (T‐I) curves provided four major sets of information for interpretation of findings: (1) maximum sensory intensity; (2) time required to reach maximum; (3) total duration of sensation, and (4) total area under the curve. Maximum oral viscosity was perceived 8.6 s after placement of the 5‐g sample into the mouth, maximum sweetness after 11.1 s, and maximum chocolate flavor after 12.9 s. The pudding had significantly greater oral viscosity than the creme, but the two products had similar time patterns for flavor. Sweetness and flavor persisted long after viscosity was no longer detectable. Although there was considerable between‐judge variation in the type of T‐I curves generated, within‐judge responses were reproducible as was the panel as a group. The usefulness of information on the time course of textural and flavor characteristics of foods and model systems during oral manipulation and swallowing is discussed.
A PRELIMINARY STUDY OF W/O/W EMULSIONS WITH A VIEW TO POSSIBLE FOOD APPLICATIONS
Authors: MATSUMOTO S. , SHERMAN P.
Published: February 2007

A study was made of the influence of various additives on the stability and low shear viscosity of water‐in‐olive oil‐in‐water emulsions. The additives were glucose, sucrose, acetic acid, citric acid, ascorbic acid, sodium chloride and sodium acetate, Glucose and sucrose increased viscosity for some time until a constant value was reached. With the other additives an initial increase in viscosity was followed by a decrease and a corresponding decrease in stability. These observations are explained in terms of the osmotic pressure gradient between the inner and outer water compartments, and the effect of additives on the physical state of the emulsifier films adsorbed at the interfaces between the two water compartments and the oil phase.
RELATIONSHIP BETWEEN THE PHYSICAL PROPERTIES OF DRIED BEANS AND THEIR TEXTURAL CHARACTERISTICS AFTER PROCESSING
Authors: ANZALDUA‐MORALES A. , BRENNAN J. G.
Published: February 2007

Baked beans in brine and in tomato sauce were prepared using samples from six different uarieties of bean. The dry unprocessed‐beans were tested by means of compression and puncture, shearing, back extrusion and compression tests, as well as to sensory evaluation of texture.

For canned beans in brine, the maximum forces for compression and back extrusion were found to be linearly dependent on the maximum force for compression of the dry beans. In the case of beans canned in tomato sauce, only the maximum force for back extrusion exhibited linear dependence. When tomato sauce was used, some softening was observed. The maximum force for back extrusion was correlated to sensory firmness, and the energy for back extrusion to sensory chewiness.
BOOK REVIEW
Authors: MORTON I.E.
Published: February 2007

Source Book of Food Enzymology. S. Schwimmer. AVI Publishing Co., Inc., Westport, Conn. 967 pp., 1981. U.S. $85.00. Other Countries $93.50.
RELATIONSHIPS BETWEEN SENSORY ATTRIBUTES IN COOKED MEAT
Authors: DRANSFIELD E. , FRANCOMBE M. A. , WHELEHAN O. P.
Published: February 2007

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TEXTURE CONTRASTS AND COMBINATIONS: A VALUED CONSUMER ATTRIBUTE
Authors: SZCZESNIAK ALINA S. , KAHN EARL L.
Published: February 2007

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DEVELOPMENT AND APPLICATION OF A TEXTURE PROFILE FOR U.K. BEEFBURGERS
Authors: DRANSFIELD E. , JONES R. C. D. , ROBINSON J. M.
Published: February 2007

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MECHANICAL PROPERTIES AND TEXTURE OF STORED APPLES
Authors: HOLT J. E. , SCHOORL D.
Published: February 2007

Granny Smith, Delicious and Jonathan apples were placed in cool store immediately after harvest and were tested for ultimate tensile strength, fracture resistance and hysteresis of tensile specimens, and bruise resistance of whole apples under slow and impact compression over a period of 18 weeks. Sensory panel assessments of apple flesh texture were also made. Ultimate tensile strength and fracture resistance showed strong negative correlations with time for all varieties. Ultimate tensile strength decreased from 200–300 kPa at the beginning of the test period to 10 kPa at the end. Fracture resistance fell from 200–300 Jm−2 to 10 Jm−2 over the same time. The hysteresis ratio was unaffected by storage time but showed some effect of conditioning at 20° C for one week. Hysteresis ratios were between 0.1 and 0.2. Bruise resistance also remained fairly constant over the storage period for all varieties for both slow and impact compression. The explanation of this behaviour is the increase in the number of ruptured cells per unit volume of bruised tissue as storage time increases. Sensory panel assessment showed an inability to sense long term textural changes. There was, however, good correlation between panel assessment, ultimate tensile strength and fracture resistance for varietal effects and storage treatments. The tensile properties of apple tissue, namely, ultimate tensile strength and fracture resistance, provide a good measure of deterioration of apples during storage.
CORRELATION OF MECHANICAL PROPERTIES, COMPOSITION AND PERCEIVED TEXTURE OF BEEFBURGERS
Authors: JONES RICHARD C. , DRANSFIELD ERIC , ROBINSON JEFFREY M. , CROSLAND ADRIAN R.
Published: February 2007

Twenty‐five brands of beefburgers were bought at retail in the United Kingdom, and their weights and dimensions, chemical composition, compressive strength and expressible fluid measured before and after grilling and compared with sensory evaluations. Compressive strength of grilled burgers measured with a punch and die, averaged 2.6 × 104 Nm−2 and varied from 1.1 to 4.6 × 104Nm−2 between brands. Beefburgers with a more rubbery, cohesive and coarser, tougher texture had higher compressive strength, higher total nitrogen, higher defatted meat content and more acceptable texture. The major variation in texture between brands was a combination of the sensory attributes rubberiness and tenderness of particles, and 70% of that principal component was accounted for by linear combination of three objective variables with measurements of strength predominant. The second principal sensory component, composed mainly of moistness and comminution attributes, was related to chemical assays and expressible fluid. These findings support the interpretation of the sensory profile as a primary component involving behaviour under stress and strain and a secondary involving perception of structure, composition and moistness.
INSTRUMENTAL AND SENSORY TEXTURE ASSESSMENT AND FRACTURE MECHANISMS OF CHEDDAR AND CHESHIRE CHEESES
Authors: GREEN M. L. , MARSHALL R. J. , BROOKER B. E.
Published: February 2007

Textural attributes of Cheddar and Cheshire cheeses, falling within narrow compositional ranges, were assessed by sensory panels, and from force‐compression curves generated by compression between two plates, and, for Cheddar cheese only, by penetrometry. Individual sensory measurements did not relate well to any instrumental one, and were better at discriminating between cheeses. Samples of each cheese variety were fractured in different ways and the fracture surfaces were examined in a scanning electron microscope. Fracture surfaces were formed by cutting directly through the matrix, tearing of the matrix along planes high in fat or cracking at grain boundaries. It is suggested that consideration of fracture mechanism may aid the selection and development of useful instrumental methods for texture assessment of cheese.
COMPARISON OF FORCE‐DEFORMATION CHARACTERISTICS OF ARTIFICIAL AND SEVERAL NATURAL FOODS FOR CHEWING EXPERIMENTS
Authors: OLTHOFF L. W. , VAN DER BILT A. , DE BOER A. , BOSMAN F.
Published: February 2007

The masticatory performance of an individual has been quantified by determining the particle sizes of the comminuted food. Optosil, a silicon rubber, has been used as an artificial test food in clinical studies, because it has reproducible textural properties. A comparison between Optosil and several natural foods was made by measuring textural properties of Optosil, turnip, carrot, Gouda cheese and peanut. Several types of probes were used to imitate the cusp form of the teeth. Force‐deformation plots revealed similar maximum firmness for Optosil, turnip and carrot, whereas peanut showed a larger firmness. The force needed to crush Optosil is much larger than for the natural foods, but it is well within the physiological range of healthy subjects. The reproducibility of the textural properties is better for Optosil than for the natural foods. The particle size distribution of Optosil broken by a testing machine was compared with the results obtained during chewing.
RHEOLOGY OF APPLE AND POTATO TISSUE AS AFFECTED BY CELL TURGOR PRESSURE
Authors: LIN TA‐TE , PITT R. E.
Published: February 2007

Experiments were performed on two varieties of apple tissue and one variety of potato tissue, in which cell turgor pressure was varied and the concomitant mechanical properties of the tissue were tested. Turgor pressure was controlled by immersion in solutions of various mannitol concentrations, and the degree of swelling or contraction of the tissue samples was measured. Under constant‐strain‐rate loading, mode of failure varied among the different commodities, and underwent a transition as the turgor pressure was varied. Rate of loading also caused a transition in failure mode. The stress and strain at failure and tissue stiffness were related to mode of failure, turgor pressure, and strain rate. From the osmotic swelling data, estimates were made of the cell wall stress‐strain behavior and of the probability distribution for cell‐wall strength in Ida Red apple tissue.
COMPARISON BETWEEN PROJECTED MECHANICAL EQUILIBRIUM CONDITIONS OF SELECTED FOOD MATERIALS IN STRESS RELAXATION AND CREEP1
Authors: PURKAYASTHA S. , PELEG M.
Published: February 2007

Asymptotic modulus versus strain relationships in stress relaxation tests of potato flesh, cheddar cheese and 1.5% agar gels were compared to similar relationships derived from creep experiments. The asymptotic moduli (or compliance reciprocals) were on the same order of magnitude and their dependency on the strain of a similar character. These suggest that despite the history sensitive response of food materials, their mechanical equilibrium conditions are governed by the same structural features.