bluuebunny/crossref_metadata_2025_split huggingface dataset:
DESKTOP COMPUTER BASED COLLECTION AND ANALYSIS OF CREEP‐COMPLIANCE DATA ON FLUID FOODS
Authors: RAO M. A. , KASH S. F. , COOLEY H. J. , BARNARD J. 
Published: February 2007

ABSTRACTIn a creep‐compliance test, the strain due to an imposed stress is recorded as a function of time. Subsequently, the strain is converted to creep‐compliance and the rheological parameters: compliances, retardation times, and viscosities are evaluated by a graphical method suggested by Inokuchi. A Macintosh Plus microcomputer was programmed in Basic language to collect time‐strain data from a Deer Rheometer III. A Fortran language program was written first to compute creep‐compliance from strain and subsequently to estimate rheological parameters using a nonlinear parameter estimation subroutine. Initial values for the nonlinear analysis were estimated by the computer program by means of a modified Inokuchi's method.
INFLUENCE OF FRICTION, SAMPLE DIMENSIONS AND DEFORMATION RATE ON THE UNIAXIAL COMPRESSION OF RAW POTATO FLESH
Authors: CANET W. , SHERMAN P. 
Published: February 2007

ABSTRACTThe influence of surface friction and lubrication on the compression behavior, at compression rates of 5–100mm min−l, of cylindrical samples of potato flesh have been examined with an Instron Universal Testing Machine at room temperature. The samples had length/diameter ratios of 0.2–0.8. Parameters derived from compression to failure were: failure stress; failure strain; and apparent modulus of elasticity. Stress relaxation with time was studied using samples with length/diameter ratios of 0.4–0.8 following compressions of 10 and 30%. The length/diameter ratio, rate of compression, surface friction and lubrication influenced the parameters derived from both the compression and the stress relaxation tests. Relaxation times increased following sample lubrication. The effect due to surface lubrication was smaller than in previous compression and relaxation tests on Gouda cheese. This was attributed to release of fluid from the damaged cellular tissue of the potato flesh which reduced the effectiveness of the lubricant film.
ACETIC ACID MARINADING—THE RHEOLOGICAL CHARACTERISTICS OF SOME RAW AND COOKED BEEF MUSCLES WHICH CONTRIBUTE TO CHANGES IN MEAT TENDERNESS
Authors: RAO M. V. , GAULT N. F. S. 
Published: February 2007

ABSTRACTThe tensile and adhesive characteristics of acetic acid marinaded bovine Ms sternomandibularis (StM), infraspinatus (IS), triceps brachii caput longum (TB), and psoas major (PM) were studied over the meat pH range 5.80 to 4.10 on both raw and cooked strips of muscle. In the raw muscle samples, tensile and adhesive characteristics were greatest around pH 5.0, progressively decreasing as muscle pH values approached 4.1. Cooking increased tensile strength, particularly around pH 5.0 where peak force values virtually doubled. Cooking had less influence on the adhesive characteristics of all muscle samples which tended to decrease below pH 4.5. In both raw and cooked muscle samples, intermuscular differences in adhesive characteristics were also much greater than those obtained for tensile characteristics. Irrespective of intermuscular differences in collagen content or its degree of maturity, the gradual decreases in tensile and adhesive characteristics below pH 5.0 could be related to the effect of acetic acid induced swelling on both muscle fibres and the connective tissue network. The influence of acetic acid marinading in promoting meat tenderness is due more to its effect on the behaviour of the muscle fibres during cooking than to its effect on the connective tissue network of different muscles.
VISCOELASTICITY OF GELATINIZED STARCH DISPERSIONS
Authors: EVANS I.D. , LIPS A. 
Published: February 2007

ABSTRACTData are presented for the elastic moduli of gelatinised dispersions of a range of starch types, including native and chemically modified starches, over a much wider concentration range than examined heretofore. As found previously, there is a threshold concentration for measurable elasticity, near the close‐packing point, and a concentration region above this over which elasticity increases roughly linearly with concentration. A second, higher, “threshold” concentration at which a fairly sharp slope change occurred was also found. Three types of behaviour were found, apparently corresponding to the distinction between chemically modified starches, root and tuber starches, and cereal starches. At the second threshold concentration these, respectively, showed a significant fall in slope, little or no slope change and a marked slope increase. A recent study (Evans and Lips 1990) has provided a useful description of the elastic properties of concentrated dispersions of model deformable particles. Comparison between the behaviour of the “baseline” model dispersions with that of the starch dispersions examined here reveals significant similarities, especially when considering the behaviour of the chemically modified starches. There are some noteworthy differences which raise important questions about the structural origins of the rheological properties of starches and we briefly speculate about these.
RHEOLOGICAL CHARACTERIZATION OF STIRRED YOGHURT: VISCOMETRY
Authors: SKRIVER A. , ROEMER H. , QVIST K.B. 
Published: February 2007

ABSTRACTRheological characteristics of stirred yoghurt, varying in dry matter content, fermentation temperature and composition of bacteria cultures, were evaluated using a Bohlin VOR Rheometer. Flow curves, covering the shear rate range 29–920 s−1, generally indicated the presence of a yield point and pseudoplastic behaviour, but also Bingham plastic behaviour was observed for some of the specimens. Systematic variations in the profile of the flow curves were observed as a result of the applied manufacturing conditions. Flow curves exhibiting pseudoplastic behaviour with a yield stress could not, over this broad shear rate interval, be described satisfactorily by the often applied Casson or Herschel‐Bulkley models, and consequently a new one, the QRS‐model was introduced. This model contains three parameters and gave a significantly better fit, with R2 values generally above 0.99.
DO IRREGULAR STRESS‐STRAIN RELATIONSHIPS OF CRUNCHY FOODS HAVE REGULAR PERIODICITIES?1
Authors: PELEG MICHA 
Published: February 2007

ABSTRACTThe attractors of the jagged, normalized, dimensionless, stress‐strain relationships of three dry snacks, breadstick, pretzel and Zwieback, were constructed using the Packard‐Taken method. No unambiguous pattern could be revealed but the shape of the attractors differed from that of a totally random sequence. Although the existence of underlying characteristic periodicities could not be proven using the method with the available data it could not be ruled out either.
HARDNESS OF COOKED MILLED RICE BY INSTRUMENTAL AND SENSORY METHODS
Authors: PEREZ CONSUELO M. , JULIANO BIENVENIDO O. , BOURNE MALCOLM C. , ANZALDÚA‐MORALES ANTONIO 
Published: February 2007

ABSTRACTFifteen milled rice varieties covering the usual range of amylose content and cooked rice hardness were used in a collaborative study to verify the sensitivity of the present objective method for measuring cooked rice hardness. The grains were cooked either in a rice cooker using a fixed water:rice ratio of 2:1, or by boiling in excess water for the predetermined optimum cooking time for each sample followed by draining. Hardness of cooked rice was measured in an Instron Universal Testing Machine (UTM) using two methods: (1) puncture of 100 individual grains and (2) extrusion through a 30 cm2 Ottawa Texture Measuring System (OTMS) cell with either a 3.2‐ or 4.8‐mm‐diam. holes plate. Hardness values were compared with sensory scores by a trained panel composed of 11 members. Sensory hardness of the rices cooked in a fixed amount of water showed very good correlation with puncture force (r = 0.94, P < 0.01) and with extrusion force through a 3.2‐mm‐diam. holes plate (r = 0.94). The correlation coefficient between puncture force and extrusion force was 0.97. Paired comparison test by the sensory panel on three pairs of rices verified consumers’ claims with respect to preference between members of each pair and agreed with results of ranking test.
YIELD STRESSES IN MOLTEN CHOCOLATES
Authors: WILSON LAURIE L. , SPEERS R. ALEX , TUNG MARVIN A. 
Published: February 2007

ABSTRACTYield stress and flow properties of four molten chocolate samples at 40C were measured using coaxial cylinder and vane fixtures. The possibility for slip to occur during measurement was demonstrated by significant differences (p < 0.05) in Gasson parameters when measured between coaxial cylinders of different radius ratios. Significant differences in the Casson flow parameters (p ≤ 0.05) were also found when samples were sheared for 12 min as compared to 30 min. A piecewise regression technique, which fitted the Casson model to the low shear rate ranges and the Bingham model to higher shear rate ranges, could be used to best describe the flow behaviour of chocolate melts. Stress relaxation produced very low oy values, which were believed to be an artifact of the measuring fixture and instrument. In the case of the single vane method, use of different start‐up speeds had a marginal but significant effect (p < 0.05) on oy values. When the multiple vane method was employed, start‐up speeds below 0.23 rpm had no significant effect on oy. The multiple vane method proved to be simple and more rapid than obtaining the steady shear data and then fitting the Casson flow model, and thus may be more suitable for routine yield stress measurements of molten chocolate for quality assurance purposes.
BITE FORCES AND HARDNESS PERCEPTION IN PRODUCTS PRESENTING PLASTIC DEFORMATION
Authors: MIOCHE L. , QUEMAR J. C. , CULIOLI J. , WODA A. 
Published: February 2007

ABSTRACTThe oral perception of the hardness of plastic deformable products was investigated. Differential sensitivity was studied over a large range of hardness during psychophysical tests in which bite forces were recorded with small intra‐oral load cells. The mechanical properties of 21 products obtained from dental waxes and modelling clays were measured. They covered a stress range from 19N/cm2 to 265N/cm2 when the plastic deformation plateau was reached. For psychophysical experiments, these products were divided into four series according to their hardness. For each series, a differential threshold was obtained for 10 individuals who were asked to make hardness comparisons by biting the samples with the incisors. During each bite, forces were recorded from an intra‐oral load cell placed beneath the sample. Differential thresholds varied between 6 and 13% depending on the series. For the 21 products taken together, a significant correlation (R = 0.98) was found between bite forces and stresses. Furthermore, significant correlations were also found within each series of comparisons except for the series of the softest products. Bite forces appeared therefore to play the main role in hardness perception of products exhibiting plastic deformation, except for the softest products for which developed forces might not correspond to the normal field of forces activated during mastication.
EVALUATION OF THE HOLE PRESSURE METHOD TO MEASURE THE FIRST NORMAL STRESS DIFFERENCE OF CORN MEAL DOUGH DURING EXTRUSION COOKING
Authors: BHATTACHARYA M. , PADMANABHAN M. 
Published: February 2007

ABSTRACTRheological properties of food dough melt, such as steady shear viscosity (η) and first normal stress difference (N1), were measured using an in‐line slit die rheometer attached to a laboratory model single‐screw extruder. The flow rate through the rheometer was varied by altering the screw speed. Alternatively, a sidestream valve, to vary the flow rate through the rheometer at fixed screw speed, was also used to obtain rheological data. The slit die rheometer was tested with corn meal at three different experimental conditions: 25% and 35% moisture contents at 180C barrel temperature and 35% moisture content at 150C barrel temperature. N1 was measured using the hole‐pressure and exit‐pressure method. Exit pressure measurements were found to be erratic and unreliable. Hole pressure increased monotonically with increasing flow rate and was found to be affected by the processing history. The magnitude of the hole pressure ranged between 2% and 21% of pressure of the flush mounted transducer. For the experimental conditions used in this study, N1 ranged from 3 × 104 to 6 × 105 Pa for shear rates between 30 to 400 s−1. Possible sources of errors in the hole pressure measurements are discussed.
PENDULUM TEST FOR EVALUATION OF THE RUPTURE STRENGTH OF SEED PODS
Authors: LIU X‐Y , MACMILLAN R. H. , BURROW R. P. , KADKOL G. P. , HALLORAN G. M. 
Published: February 2007

ABSTRACTA small impact pendulum was developed to measure the shatter resistance of seed pods. While clamped by their stems, the pods are hit by the rigid pendulum; the rupture energy is derived from the measured angles of swing. The consistency of the pendulum was confirmed by tests on a sample of fine spring wire. The pendulum was then used in a series of trials on 13 rapeseed varieties and rupture energy results were compared with earlier bending moment and bending energy results obtained from tests using a quasi‐static cantilever arrangement. Rupture energy values were much less variable than bending energy. However, the ranking of varieties by all three strength measures was generally similar.
FIBRE FRACTURE OF BOVINE M. PECTORALIS PROFUNDUS MUSCLE COOKED PRE‐ AND POSTRIGOR
Authors: DRANSFIELD ERIC , LACOURT ANDRE , LACOURT PAULETTE 
Published: February 2007

ABSTRACTThe ultimate tensile strength and extensibility in the direction of the muscle fibres of cooked meat decreased exponentially during storage of the raw meat for up to 3 days at 15C. The mode of fracture was examined by light microscopy of longitudinal sections taken after testing to break. In meat cooked soon after stunning, ‘brittle’ fracture had been induced across the fibres and the high extensibility was proposed to be due to sequential fibre fracture. At 1 day postmortem, the fractures crossed several fibres occurring in a repetitive fashion every 30 μm along the fibres. This was thought to be due to a stiff fibre embedded in an extensible surface matrix connecting the fibres. In aged meat, discontinuous fractures were prominent within each fibre and which stopped at the surface of each fibre showing further weakening of the fibre and the composite matrix. All the myofibrils remained in register. These changes are consistent with a gradual reduction in cohesion within the meat and indicates that the weakening of the focal adhesions is primarily responsible for postmortem tenderisation.
DYNAMIC VISCOELASTICITY AND STRESS RELAXATION IN STARCH PASTES
Authors: AKUZAWA SAYURI , SAWAYAMA SHIGERU , KAWABATA AKIKO 
Published: February 2007

ABSTRACTThe dynamic viscoelasticity and stress relaxation of ten types of starch pastes were measured. The dynamic moduli increased with increasing frequency, and were different for each starch paste, changes in tan δ for cassava and potato starch pastes being about 0.5–0.6. The stress relaxation behaviour of all the samples tested could be represented by a four‐element mechanical model. The relationship between spinnability and stress relaxation was determined, the spinning distance increasing with increased relaxation time (τ2). No satisfactory linear relationship between spinning distance and relaxation time (τ2) was apparent with the 10 starch paste samples.
A VIDEO‐BASED METHOD FOR DETERMINATION OF AVERAGE STRESS‐STRAIN RELATIONS IN UNIAXIAL COMPRESSION OF SELECTED FOODS
Authors: ROHM H. , JAROS DORIS , DeHAAN MARGREET 
Published: February 2007

ABSTRACTA video‐based method was applied to evaluate average stress‐strain relationships during uniaxial compression experiments of selected food materials. The determination of apparent Poisson ratios of Gouda cheese resulted in numbers close to the theoretical value for incompressible materials of 0.5. In case of such foodstuffs, mathematically corrected compressional stress based on the consideration of constant specimen volume showed almost similar results to stress values estimated on the basis of the true cross‐sectional area measured from lateral extension. For compressible materials such as apples or bread, which show a certain reduction of volume under stress or strain, the apparent Poisson ratios were strain‐dependent. Average stress values calculated from compressional force and actual specimen diameter were found to be different from either engineering stress and corrected stress.
SMALL AMPLITUDE OSCILLATORY SHEAR STUDIES ON MOZZARELLA CHEESE PART II. RELAXATION SPECTRUM
Authors: SUBRAMANIAN R. , GUNASEKARAN S. 
Published: February 2007

ABSTRACTThe frequency dispersion of dynamic mechanical spectra of a low‐moisture, part‐skim and a low‐fat, part‐skim Mozzarella cheese are presented. Small amplitude oscillatory shear measurements within the linear viscoelastic range (0.05% strain) were made over 12 weeks of storage. Proteolysis during storage led to softening of the cheeses and thus decreases in storage (G′;) and loss (G″) moduli. Master curves (at a reference temperature of40C) were obtained by shifting the temperature‐dependent frequency dispersion of storage modulus. There was no significant change in G’ after 4 weeks of aging. The variation of relaxation time and viscosity spectrum of both cheeses with age were obtained from the master curves using the generalized Maxwell model and nonlinear regression analysis. With maturation the viscosity distribution of corresponding Maxwell elements shifted towards smaller values, indicating that cheeses become softer and melt more easily.
METHOD TO ASSESS THE ABILITY OF ROUGH SURFACES TO ELIMINATE SLIP IN FOOD VISCOMETRY 1
Authors: HOFFNER B. , GERHARDS CH. , PELEG M. 
Published: February 2007

ABSTRACTIn squeezing flow viscometry the presence or absence of friction between the specimen and the plates has a dramatic effect on the flow curve characteristics. It is therefore proposed that the method can be used to test whether a given surface, with a particular rough finish, is effective to eliminate slip of a given self‐lubricating food. The concept is demonstrated with experimental data of commercial samples of mayonnaise and mustard, which were pressed between pairs of parallel polished and rough metal plates in an imperfect squeezing flow array, and their force height relationship was recorded. In all the cases, the absolute magnitude of slope of the log‐force versus log height plot was smaller than one. This shows that these two products are self‐lubricating to such an extent that roughening of the plates surface, at least to the extent used in this work, can be an ineffective means to avoid slip. Similar results have been previously reported in three different kinds of tomato products, which suggests that the problem may not be limited to food emulsions.
TEXTURE AND STRUCTURE OF CRISPY‐PUFFED FOOD PRODUCTS PART II: MECHANICAL PROPERTIES IN PUNCTURE
Authors: VAN HECKE E. , ALLAF K. , BOUVIER J. M. 
Published: February 2007

ABSTRACTA puncture test was used to describe the mechanical and textural behavior of crispy‐puffed food extrudates. Four criteria were identified from the force‐time curves: (1) the average puncturing force, Fm, (2) the spatial frequency of structural ruptures, Nwr, (3) the average specific force of structural ruptures, fwr, and (4) the crispness work, Wc. The discriminating power of these criteria was shown through the effects of moisture content and recipe composition in the extrusion‐cooking process. Relationships between puncture criteria were also studied. The effect of water activity showed that the force related criteria described well the mechanical behavior of expanded extrudates.
MECHANICAL PROPERTIES OF AN IMMERSION FRIED POTATO STARCH‐GLUTEN GEL DURING POSTFRYING PERIOD
Authors: NORMÉN EVA , ROVEDO CLARA O. , SINGH R. PAUL 
Published: February 2007

ABSTRACTMoisture profiles in fried samples of potato starch with different gluten contents were determined during postfrying storage. Over time, moisture migrated from the core to the crust of the sample, and the moisture content of the crust region increased. The addition of gluten caused a significant increase in oil uptake in the crust. The initial hardness of the crust significantly decreased as the gluten content increased to 10 and 30%, during the first 30 min of storage. With longer storage time (> 240 min), the crust hardness tended to increase, due to an increase in firmness of the starch sample. This behavior was less pronounced for samples with 10 and 30% gluten. The range of linear viscoelastic behavior (up to 14% strain) was determined from the initial linear zone of the stress‐strain curves. Stress relaxation tests were performed in the linear and nonlinear viscoelastic regions, with a strain level of 5% and 40%, respectively. According to stress relaxation curves, samples became less elastic with the addition of gluten and more elastic with the time of storage.
EFFECTS OF GELLAN GUM, CITRIC ACID AND SWEETENER ON THE TEXTURE OF LEMON JELLY
Authors: MORITAKA HATSUE , NAITO SHIGEHIRO , NISHINARI KATSUYOSHI , ISHIHARA MIKI , FUKUBA HIROYASU 
Published: February 2007

ABSTRACTEffects of various ingredients on the texture of lemon jellies prepared from gellan gum, citric acid and sweetener were investigated by rheological measurement and sensory evaluation. The data were analyzed by use of the modification of Scheffé's mixture experiment method in converse triangle experiment area. The contours of the response surface were drawn using the best model whose terms were searched by AIC statistic, and the approximate model was calculated to consider the contours. “Hardness” estimated by both methods was large in jellies with high content of gellan gum and low content of citric acid. The content of citric acid significantly influenced “smoothness” estimated by a subjective method. The influence of citric acid varied with the content of gellan gum. The correlation coefficients of evaluation between “hardness” and “lemon flavor” or “sourness” were negative.
FORMATION OF WHEY PROTEIN POLYMERS: EFFECTS OF A TWO‐STEP HEATING PROCESS ON RHEOLOGICAL PROPERTIES
Authors: MLEKO S. , FOEGEDING E.A. 
Published: February 2007

ABSTRACTWhey protein polymers were obtained by two‐step heating of whey protein isolate (WPI) solutions with or without change of pH or protein concentration. Rheological properties of polymer solutions were studied. Viscosity of solutions heated then diluted was about 6 times higher than viscosity of equal concentration solutions heated directly. A second heating at a lower pH resulted in higher viscosity. Solutions were generally thixotropic and pseudoplastic; however, dilatant and rheopectic behavior was also observed. A 4% WPI solution could be converted to a polymer solution with a viscosity comparable to the viscosity of 1% carbohydrate hydrocolloids.
FEASIBILITY OF MEASURING MEAT TEXTURE AND EXUDATE USING PAIRED HYPODERMIC NEEDLES FOR RHEOLOGY, SPECTROPHOTOMETRY AND ELECTRICAL IMPEDANCE
Authors: SWATLAND H. J. 
Published: February 2007

ABSTRACTMeat texture and exudate were investigated using a pair of hypodermic needles curved to touch at their tips. Electrical impedance was better than fiber‐optic spectrophotometry for detecting the meat exudate released as the needles were moved apart. Separation of needles creating tension along the lengths of myofibers caused higher stress and less tip separation than needle separation perpendicularly across the myofibers.