bluuebunny/crossref_metadata_2025 huggingface dataset:
DISCUSSION OF THE BINDING QUALITY OF MINCED MEATS BASED ON THEIR RHEOLOGICAL PROPERTIES BEFORE AND AFTER HEATING
Authors: SATO YASUSHI , NAKAYAMA TERUO
Published: February 2007

Abstract Raw fish meat and three muscle groupings of cockerel meat were analyzed for total nitrogen, myofibrillar and sarcoplasmic proteins, non‐protein and residual nitrogen, fat, pH, moisture and hydration capacity. Stress relaxation measurements were made on both raw and heat coagulated samples. Tensile strength measurements were made on heat coagulated samples. Using breaking energy as an index of binding, myofibrillar protein content and hydration were tentatively related to binding quality. Equilibrium modulus values offered an indication of the presence of crosslinking after heating. The rheological behavior of fish meat could be explained by a seven element model and that of cockerel meat by a five element model before heating. An analysis is presented of the mathematical treatment of rheological measurements and their relationship to binding quality and chemical composition of the tested samples.
FLOW BEHAVIOUR OF CONCENTRATED ORANGE JUICE*
Authors: MIZRAHI SHIMON , BERK ZEKI
Published: February 2007

Abstract Orange concentrate, at the 60‐65° Brix concentration level, is a non‐Newtonian fluid with yield stress and time dependent behaviour. While recovery from low‐rate shear is reversible, shear at high rate causes irreversible destruction of the viscous structure. Part of this effect is due to disintegration of pulp particles. Pulpless concentrate (serum) is also non‐Newtonian, but yield stress and time dependent behaviour are present only when pectin concentration is high. Depectinized serum is Newtonian. The effect of temperature on flow properties of all three types of material was studied.
ON POWER EQUATIONS RELATING STRESS TO SHEAR RATE IN RHEOLOGY
Authors: BLAIR G. W. SCOTT
Published: February 2007

A brief outline is given of the use history of power equations in rheology and dimensional difficulties are discussed. No complete explanation is yet available for the very wide application of these equations, but a few special cases are cited. Possible applications to texture studies are considered.
COLLECTION AND CLASSIFICATION OF WORDS FOR DESCRIPTION OF FOOD TEXTURE
Authors: YOSHIKAWA S. , NISHIMARU S. , TASHIRO T. , YOSHIDA M.
Published: February 2007

Using a controlled association test, Japanese expressions describing texture were collected in response to 97 food stimulus words. Results were compared with those obtained by Szczesniak in the United States. Frequencies of response were well balanced for some but not for all words with opposite meanings. There were many onomatopoeic words. The median frequency of mention per subject per food was about 3.5 texture words. This became about 7 when words which were mentioned only once were omitted. In the descending order of frequency, the most important words were: hard, soft, juicy, chewy, greasy, viscous, slippery, creamy, crisp (kori‐kori), crunchy (kari‐kari), and brittle.
RELATIONSHIPS BETWEEN BINDING QUALITY OF MEAT AND MYOFIBRILLAR PROTEINS: III: Contribution of Myosin A and Actin to Rheological Properties of Heated Minced‐Meat Gel
Authors: NAKAYAMA TERUO , SATO YASUSHI
Published: February 2007

Myosin A and myosin B gels formed by heating exhibited similar binding abilities as measured by the breaking energy, but different physical properties. At equivalent concentrations, myosin A gels exhibited smaller values for the Young's modulus of elasticity and larger values for strain at the breaking point. It was inferred from the results of a simple model experiment that in sausage manufacture the physical properties of the heat set minced meat gel are of the myosin B type when no pyrophosphate is present, and similar to the myosin A type when pyrophosphate is added. In the latter case, the contribution of actin may be significant. The binding quality of the heat set myosin B gel increased with myosin concentration. Hence, the binding quality of sausage should be influenced by the myosin B content of meat.
MODERNIZATION OF TEXTURE INSTRUMENTATION *
Authors: VOISEY PETER W.
Published: February 2007

Abstract. The use of electronic instruments to record force and deformation in objective texture measurements is reviewed to point out that much equipment is available for that purpose and to indicate some of the problems associated with its use. Electronic transducers are universally applicable to texture measuring systems and can give precise measurements with a high degree of resolution.

Several examples of modernized texture instruments are described to demonstrate different methods of approach. Special purpose or ‘universal units’ can be developed. It is concluded that force and deformation can be recorded by electronic techniques in any textural test but that the interpretation of the data is the major problem.
PEA TEXTURE STUDIES USING A SINGLE PUNCTURE MATUROMETER*
Authors: CASIMIR D. J. , COOTE G. G. , MOYER J. C.
Published: February 2007

The operation of the single puncture maturometer is described. A linear regression relationship was established between single puncture maturometer readings (SPMR) and commercial maturometer readings. Various parameters of the force distance curve obtained during puncturing of individual peas were found to be related to gross chemical composition and maturity. Maximum force showed the highest and a positive correlation with alcohol insoluble solids (AIS). The force required to puncture peas was independent of the hole size used but increased with increasing pin diameter; it was related to AIS and to total solids by linear regressions. SPMR of peas in a single peapod showed that all were of similar maturity.
THE INFLUENCE OF TURBULENT FLOW ON THE SENSORY ASSESSMENT OF VISCOSITY IN THE MOUTH
Authors: PARKINSON C. , SHERMAN P.
Published: February 2007

Low viscosity Newtonian fluids exhibit turbulence in a cone‐plate viscometer at high rates of shear which are comparable to those operating in the mouth during sensory assessment of the viscosity of the same fluids. Saliva reduces this effect to some small extent, possibly due to its content of mucin and other proteinaceous substances. The net result is that these fluids appear to have a higher viscosity in the mouth than when they are examined in a viscometer at low rates of shear. Higher viscosity non‐Newtonian food materials such as Carnation milk and ice cream do not exhibit turbulent flow, and the only effect exerted by saliva is a reduction in the viscosity at all rates of shear.
STRUCTURAL, RHEOLOGICAL AND TEXTURAL PROPERTIES OF SOFT PARAFFINS
Authors: BARRY B. W. , GRACE A. J.
Published: February 2007

Abstract Various aspects of soft paraffins, with the main emphasis on their rheological properties, are considered in a review of 119 references. Rheological test methods currently used are critically appraised in sections on penetrometry, continuous shear viscometry, oscillatory testing and creep analysis. The chemical nature, microscopic structure, miscellaneous methods of standardisation, formulation and work softening of petrolatums are reviewed. The textural properties of soft paraffins are discussed; a master curve of the rheological conditions operative during spreading on the skin is presented.
A QUASI‐RHEOLOGICAL MODEL ELEMENT FOR FRACTURE
Authors: DRAKE BIRGER
Published: February 2007

Abstract A model element for fracture is proposed to supplement previously described elements for elasticity, viscosity and solid friction. The new element is characterized in mathematical terms, and examples are given of its incorporation into composite models.
RHEOLOGY OF WHEAT FLOUR DOUGHS
Authors: BLOKSMA A. H.
Published: February 2007

Rheological properties of dough are important since they affect the quality of the baked product. In addition, they are interesting since they provide information on dough structure. Instruments used for quality control in mills and bakeries are reviewed. Experiments at constant stress or at constant rate of deformation are discussed as examples of experimental techniques suitable for description of dough properties in physically simple terms. Relationships between dough structure and rheological properties are also covered.
FLOW BEHAVIOUR OF CONCENTRATED ORANGE JUICE: MATHEMATICAL TREATMENT
Authors: MIZRAHI S. , BERK Z.
Published: February 2007

Based on a model of a suspension of interacting particles in a pseudoplastic solvent, a rheological equation was developed which could describe the flow properties of concentrated orange juice. The function was obtained by modifying Casson’s equation and has the following form:

image

The magnitude of the parameter ko is affected by the concentration of the suspended particles, the concentration of soluble pectin and by conditions favorable for pectin gel formation. The other two parameters, k and m, are determined mainly by the solvent properties. The mechanism responsible for the flow behaviour of the concentrated orange juice under various conditions could be predicted and explained by the properties of the components in the system.
TEXTURAL PROPERTIES OF IRRADIATED TOMATOES (CV, FLORADEL)*
Authors: AHMED E. M. , FLUCK R. C. , DENNISON R. A.
Published: February 2007

Ripe Floradel tomatoes were softer, required smaller forces to puncture and to compress, and exhibited less recovery from applied stress than the unripened fruit. Irradiation caused similar but less pronounced changes.
DEVELOPMENT OF THE ARMOUR TENDEROMETER FOR TENDERNESS EVALUATION OF BEEF CARCASSES
Authors: HANSEN LEO J.
Published: February 2007

A simple rapid non‐destructive test and apparatus were developed for quantifying tenderness of beef carcasses. A probe with ten 1/2 inch diameter needles mounted on a manifold is pressed manually two inches into the rib eye. Measurements of maximum force during penetration into the cold rib eye on the day after slaughter correlated well with subjective panel tenderness scores on the same meat cooked after one week of aging.
PREDICTING HEDONIC RATINGS OF RAW CARROT TEXTURE BY SENSORY ANALYSIS
Authors: SCHUTZ H. G. , DAMRELL J. D. , LOCKE B. H.
Published: February 2007

A trained panel was used to evaluate degrees of flexibility, hardness, chewiness, and juiciness, while an untrained panel indicated hedonic values for texture on a rating scale. A multiple regression analysis showed that 83% of the variation in the hedonic ratings could be accounted for by sensory scores on flexibility, hardness, and chewiness.
TEXTURAL PROPERTIES OF STORED AND IRRADIATED PEACHES: I. Firmness*
Authors: AHMED E. M. , DENNISON R. A. , FLUCK R. C.
Published: February 2007

Softening of Loring and Dixieland peaches due to ripening and gamma irradiation has been quantified by sensory evaluation, the Magness‐Taylor pressure tester, the Allo‐Kramer Shear Press, and the Instron Universal Testing Instrument. Irradiation induced immediate reduction in firmness, but the final softness of the stored fruit was largely independent of the radiation dose.
RHEOLOGICAL PROPERTIES OF SEMI‐SOLID FOODSTUFFSViscoelasticity and Its Role in Quality Control
Authors: DAVIS S. S.
Published: February 2007

Samples of lard and shortening have been examined by five rheological techniques: cone penetrometer, Ferranti‐Shirley cone and plate viscometer, concentric cylinder creep, creep by spherical indentor and oscillatory testing using the Weissenberg rheogoniometer. The derived data are discussed critically with reference to the measurement of parameters for use in quality control and the development of theories of fat structure based on molecular structure and chemical interaction.

Penetrometer and continuous shear viscometer measurements are not recommended. Instead, creep testing (and the calculation of viscoelastic parameters) is suggested for quality control purposes.
FRACTURE FORCE, HARDNESS AND BRITTLENESS IN CRISP BREAD, WITH A GENERALIZED REGRESSION ANALYSIS APPROACH TO INSTRUMENTAL‐SENSORY COMPARISONS
Authors: ANDERSSON YNGVE , DRAKE BIRGER , GRANQUIST ARNE , HALLDIN LARS , JOHANSSON BIRGIT , PANGBORN ROSE MARIE , ÅKESSON CAJÅKE
Published: February 2007

Flexure/compression data and sensory judgements of breaking force, hardness and brittleness were obtained for 8 brands of crisp bread, and compared with crushing vibration data obtained in another study for 6 of these brands.

Besides relating instrumental and sensory data to each other by ordinary correlation analysis, a generalized regression analysis approach was tried as an alternative to using conventional stepwise regression as a prediction tool. This approach involved the checking of all possible combinations of regression variables, combined up to 4 at a time by certain composition rules. The results showed that there was no ‘best solution’ but rather a whole set of equally well or almost equally well fitting equations.
RHEOLOGICAL ANALYSIS OF CURD FORMATION
Authors: DOUILLARD R.
Published: February 2007

The kinetic evolution of the rheological properties of milk curd can be interpreted as first order reactions. The standard explanation of Scott Blair and Burnett is still valid but leads to a different limiting value of the rigidity modulus.
GUIDELINES TO TRAINING A TEXTURE PROFILE PANEL
Authors: CIVILLE GAIL VANCE , SZCZESNIAK ALINA SURMACKA
Published: February 2007

Abstract. A texture profile panel is a valuable tool for describing and quantifying textural characteristics of food products when the panel is carefully selected, trained and maintained. Guidelines to accomplishing this goal are presented.
A SIMPLE INSTRUMENT FOR THE MEASUREMENT OF THE DYNAMIC ELASTIC PROPERTIES OF FOODSTUFFS
Authors: JASPER R. F. , BLANSHARD J. M. V.
Published: February 2007

Abstract. A versatile and inexpensive instrument for measuring the dynamic viscoelastic properties of biological tissue is described. Where the sample is rheologically ‘well‐behaved’, a simple resonance technique enables very rapid measurements to be made. The use of the machine is illustrated by some results obtained on potato tissue.
Book Review
Authors: Sherman P.
Published: February 2007

Book reviews in this article:

M. J. Schick (ed.), Polymers at Interfaces
MECHANISM AND THEORY OF STALING OF BREAD AND BAKED GOODS, AND ASSOCIATED CHANGES IN TEXTURAL PROPERTIES
Authors: WILLHOFT E. M. A.
Published: February 2007

Abstract. A critical review of the literature on the staling of bread has been presented with particular emphasis on developments during the last decade. The staling of bread has been discussed from a structural point of view with separate contributions due to starch retrogradation, a modification in the gluten structure and a partial re‐distribution of moisture from the gluten to the starch fraction of the crumb. Both model systems and studies on the natural crumb are considered including the contribution to staling of macroscopic moisture re‐distribution and deterioration in flavour volatiles. The staling of baked goods has also been reviewed and it is proposed that certain analogies from the bread situation might provide a suitable basis for an overall theory of cake staling. It seems possible that a considerable contribution to the staling of cake sponge may be due to changes undergone by the various proteins; the free moisture produced from the transforming proteins may be absorbed by the sugars and gelatinised starch. Retrogradation of starch appears to be less important than changes in the proteins during the staling of cake. Dehydration of the cake crumb is perceived to play an important role in the sensory evaluation of cake staleness.
A TECHNIQUE FOR ESTABLISHING INSTRUMENTAL CONDITIONS FOR MEASURING FOOD FIRMNESS TO SIMULATE CONSUMER EVALUATIONS*
Authors: VOISEY PETER W. , CRĚTE RENE
Published: February 2007

Abstract. A method is described for measuring the force and the rate at which it is applied to fruits and vegetables by the consumer's hands in judging firmness. Halves of the product were mounted on a force transducer, squeezed and the forces recorded. Preliminary results from an untrained panel indicated that the rates and maximum forces used by males and females are different and depend on the firmness of the product. The data also suggest that the rate of force application in sensory testing is significantly greater than that customarily used in instrumental tests.

Limitations of the technique and its potential usefulness in establishing more rational conditions for objective firmness tests are discussed.
MEANING OF TEXTURE WORDS TO THE CONSUMER
Authors: SZCZESNIAK ALINA S. , SKINNER ELAINE Z.
Published: February 2007

Abstract. A word association test administered to 102 respondents indicated that the consumer understands the qualitative meaning of texture words in the same manner as people experienced in texture evaluation. A few words such as thin, thick, dry, smooth, hard, etc. were found to have additional meanings related to characteristics other than texture. The responses were used to compile a tabulation of foods having specific recognizable textural characteristics. This tabulation should be useful in explaining the meaning of texture words to people unfamiliar with the nomenclature or in situations where a language barrier exists.
A SYSTEM FOR RECORDING DEFORMATIONS IN TEXTURE TESTS*
Authors: VOISEY PETER W. , BUCKLEY D. J. , CRĚTE RENE
Published: February 2007

An instrumental technique is described for recording food deformation in texture tests. The time required for the applied force to change between two levels is accurately recorded in digital form. Constant deformation rates are used so that deformation is directly proportional to time. The new readout is demonstrated with springs and selected foods to indicate its performance and show the inaccuracies that occur when using strip‐chart recorders to measure deformations. The response of the new system is adequate to test products with a deformability up to 3400 g mm‐1 at deformation rates up to 100 cm min‐1 with less than 3 % error.
COMPARISON OF RESULTS FROM THE USE OF THE MAGNESS‐TAYLOR PRESSURE TIP IN HAND‐ AND MACHINE‐OPERATION
Authors: BOURNE MALCOLM C.
Published: February 2007

The 5/16″ diameter tip of the Magness‐Taylor Pressure Tester (a hand‐operated instrument) was used to perform a puncture test on five different lots of apples and one variety of pears. The tip was then mounted in the Instron machine and used to puncture the same fruits. The correlation coefficient between the two methods was 0.997, indicating that the use of the Magness‐Taylor Pressure Tip in a simple hand‐operated instrument gives results that are comparable to those obtained by the power‐driven machine.
OBJECTIVE‐SUBJECTIVE ASSESSMENT OF MEAT TENDERNESS
Authors: BOUTON P. E. , FORD ANNE L. , HARRIS P. V. , RATCLIFF D.
Published: February 2007

Compression, shear, adhesion and cooking loss measurements were compared with sensory assessments of tenderness and juiciness. Multiple regression analyses of compression, shear and cooking loss accounted for 83.4% of the total variance in tenderness for samples presented to the panel as 1.5 cm cubes, and 73.2% for those presented as thin strips cut across the fibers. Cooking losses accounted for about 75 % of the variance in juiciness scores. Regression equations indicated that higher cooking losses, and hence decreased juiciness, increased sensory toughness. The relative contribution of compression (connective tissue toughness) and shear (myofibrillar toughness) measurements varied considerably with sample treatment and fiber orientation of samples as presented to the panel.
A PUNCH AND DIE TEST CELL FOR DETERMINING THE TEXTURAL QUALITIES OF MEAT *
Authors: SEGARS RONALD A. , HAMEL ROGER G. , KAPSALIS JOHN G. , KLUTER ROBERT A.
Published: February 2007

Abstract. A test ceil is described that measures the response of materials to a punch‐shear deformation. The cell, designed as a punch and die unit, was used with the Instron Universal Testing Instrument to determine the textural characteristics of several food products. Data are presented for beef muscles from US Choice and US Commercial grade animals. Sensory evaluation using magnitude estimation techniques showed high correlation with instrumental measurements. When all combinations of three sensory attributes and three instrumental properties were considered, correlation coefficients ranged from 0.92 to 0.98. Sensory judgments showed that the differences between muscles were 2 to 3 times greater than those found using the test cell, but the large scatter in panel results reduced sensitivity below that of the instrument. The panel judged the psoas major and the semiten‐dinosus from the US Commercial grade animal to be twice as tough as the same muscles from the US Choice grade animal. The biceps femoris was judged to be 4 times tougher in the Commercial than in the Choice grade animal.
IS RHEOLOGY ENOUGH FOR FOOD TEXTURE MEASUREMENT?
Authors: BOURNE MALCOLM C.
Published: February 2007

Abstract. During mastication of food a number of processes occur, including deformation and flow (rheology), size reduction (comminution), and mixing and hydration with saliva. Changes in temperature and surface roughness (rugosity) may also be important. Food researchers should realize that rheological tests describe only a portion of the physical properties sensed in the mouth during mastication.
THE INFLUENCE ON BREAD TEXTURE OF PARTIALLY REPLACING WHEAT WITH POTATO PRODUCTS*
Authors: JAIN S. , SHERMAN P.
Published: February 2007

The use of potato products in wheat bread manufacture is reviewed with particular reference to their effect on the textural characteristics of bakers' dough and fresh bread, and the changes associated with bread staling. Possible interactions between the proteins in wheat and potato are discussed. Recent developments relating to the partial replacement of wheat by potato flakes are reviewed. Their effectiveness is discussed in terms of the chemical nature of potato starch, the physical state of starch in potato flakes and the influence exerted by additives such as glyceryl monostearate and fats.
RHEOLOGY OF GELS
Authors: MITCHELL J. R.
Published: February 2007

This review covers the rheology of gels formed by macromolecular food additives. In particular agar, alginate, carrageenan, gelatin, pectin and microbial polysaccharide gels are considered. Empirical and fundamental techniques that have been applied to gels are listed and the relationship between rheological parameters and sensory assessment of texture is briefly discussed. Certain general conclusions about the dependence of the rheological properties on network composition and structure are put forward.
DIMENSIONAL CHANGES IN MEAT DURING COOKING
Authors: BOUTON P. E. , HARRIS P. V. , SHORTHOSE W. R.
Published: February 2007

Continuous measurements of changes in meat fiber length with increasing temperature during cooking showed three zones where rates of length change are significantly different. The first (> 40°C) is attributed to myofibrillar change. The second (> 55 °C) is thought to be related to connective tissue shrinkage and shows differences with myofibrillar contraction state attributable to changes in spatial orientation of collagen fibers. The third zone (> 70 °C) is believed to be due to the interaction between myofibrillar and connective tissue contraction.

Measurements of changes in cooking loss, length and cross‐sectional area of samples of contracted and stretched muscle showed that cooking losses and the decrease in the cross‐sectional area were greater in contracted samples, whilst length changes were greater in stretched samples. This has been attributed to differences in spatial orientation of connective tissue.
RHEOLOGICAL PROPERTIES OF ALGINATE GELS
Authors: MITCHELL J. R. , BLANSHARD J. M. V.
Published: February 2007

Rheological properties of alginate gels formed in various ways were studied using a parallel plate viscoelastometer and an Instron.

All the gels studied exhibited linear viscoelastic behaviour. The creep compliance‐time response was fitted by a model consisting of a Maxwell element in series with two or three Kelvin‐Voigt elements. Despite the fact that alginate gels are non‐thermoreversible the crosslinks do not appear to be permanent. Gels formed with an alginate containing a high proportion of mannuronic acid residues are weaker and more elastic than gels prepared with an alginate predominantly composed of guluronic acid residues. When the level of calcium in the gel was high, the reciprocal of the creep compliance was proportional to the square of the polysaccharide concentration. A reduction in calcium level for a given polysaccharide concentration resulted in a more elastic gel. The nature of the temperature dependence varied with the degree of crosslinking and time of measurement after application of stress. The results were explained by assuming that the creep compliance could be regarded as the sum of two components: a time independent factor given by the theory of rubber elasticity, or some modification of this, and a time dependent factor associated with the breakage of crosslinks.
THE NATURE OF ACCEPTABILITY FUNCTIONS IN TEXTURE
Authors: MOSKOWITZ HOWARD R.
Published: February 2007

This paper provides a psychophysical analysis of potential acceptability functions which may be applicable to food texture responses in particular, and to other stimuli in general. Specific hedonic functions for acceptability would follow a generalized quadratic function, with the parameters governed by the specific food system. A two step combination of simple psychophysical (subjective intensity vs. physical intensity) and psychological (subjective intensity vs. subjective acceptability) relations may provide an easier representation of texture acceptability than predictions derived from the knowledge of physical properties of food (viz. texturogens).
THICKENING OF SOY PROTEIN SUSPENSIONS WITH CALCIUM*
Authors: LEE CHERL‐HO , RHA CHOKYUN
Published: February 2007

The objective of this study was to increase the apparent viscosity of 1‐7% soy protein suspensions using calcium. The thickening effect, measured by apparent viscosity, depended upon the calcium concentration. Maximum apparent viscosity was obtained with a calcium to protein molar ratio of 20‐50 moles of calcium required per mole of protein (M.W. 100 000) decreased with an increase in the protein concentration. Effective stirring was necessary during and after calcium addition to attain maximum thickening and stability. Heat treatment of the protein suspension prior to calcium addition enhanced the extent of apparent viscosity increase. Higher protein concentration, improved stability of the thickened mixture. The established optimum thickening conditions leading to a stable homogenous suspension involved addition of 12.5 mM CaCl2to 5% protein suspension preheated at 80 d̀C for 30 min.
PECTIN, STARCH AND TEXTURE OF POTATOES: SOME PRACTICAL AND THEORETICAL IMPLICATIONS
Authors: REEVE R. M.
Published: February 2007

This review emphasizes the interrelationships between starch and pectins as factors determining different textural qualities of potatoes. It includes examples of texture control through processing treatments affecting the different ways in which pectins are involved in textumi qualities and tissue (celi) sloughing. Previously unpublished observations on cell sloughing and cell rupturing also are included.
RHEOLOGICAL PROBLEMS IN THE FOOD INDUSTRY1
Authors: SZCZESNIAK ALINA SURMACKA
Published: February 2007

Rheological problems in the food industry deal with the elucidation of structure, processing and handling behavior, and description of textural properties affecting consumer acceptance. Many pmblems are common to other industries, but a number are specific to foods due to the complex nature of the test materials and specific requirements. Application of rheology to foods is difficult but challenging, offers much opportunity for creativity, and has practical and social connotations.
MEASUREMENT OF FLOW PROPERTIES OF FLUID FOODS ‐ DEVELOPMENTS, LIMITATIONS, AND INTERPRETATION OF PHENOMENA
Authors: RAO M. A.
Published: February 2007

Rheological behavior of fluid foods is described with examples under each type of behavior. Benefits of fundamental rheological data are illustrated for engineering studies, sensory evaluation, and detection of compositional changes. Some problems likely to be encountered due to sampling are discussed along with possible remedies. Theoretical bases for the proper use of capillary, concentric, and plate and cone visco‐ meters are outlined as well as the effects of violating the theoretical requirements. Xeld stress and rheological equations employed to describe foods possessing yield stress are reviewed. Use of mixers as viscometers for studying flow properties of foods is covered.
SALAD DRESSINGS—PRELIMINARY RHEOLOGICAL CHARACTERIZATION1
Authors: ELLIOTT J. H. , GANZ A. J.
Published: February 2007

The Weissenberg rheogoniometer was used to characterize a number of commercial mayonnaises and salad dressings. Steady shear measurements were used to determine flow properties and to estimate the degree of structure breakdown with shear. Dynamic measurements, at strain amplitudes greater than the linear uiscoelastic limit, were made to establish the properties of the essentially undisturbed samples. The results were analyzed in terms of the parameters of a modified Bingham body. Ranges for the various rheological properties of commercial salad dressings were established.
APPARENT VISCOSITY OF CHEWING GUM
Authors: BOGATY H. , TALMAGE J. M.
Published: February 2007

Deformation tests of chewing gums with a parallel‐plate plastometer are described using a variety of test conditions of load, specimen diameter and thickness. The observed behavior can, by modification of earlier theory for this mode of testing, be described in an internally consistent way by assuming the viscosity to be non‐Newtonian and proportional to a power of the average shear rate; the elastic components are assumed to be small enough to be disregarded.

The results under diverse test conditions appear to be in accord with the modified theory and to fit the proposed equations well. The computed viscosity at a reference shear rate (herein 10‐3sec‐1) is a useful parameter which appears to relate to stateness of various samples, to water loss on aging and to test temperature, to which the apparent viscosity is appropriately sensitive. Comparison of different materials, especially if the test time is fixed, appears to be feasible with the procedurally simple technique using the described algebraic relationships.
TEXTURE CHARACTERIZATION OF VEGETABLE PROTEIN PRODUCTS MARKETED IN JAPAN
Authors: SAIO KYOKO
Published: February 2007

A large number of commercial vegetable protein products based on soybeans and wheat were tested for functional properties and textural characteristics. Powder and paste products were tested for moisture, protein content, nitrogen solubility, whipping properties, emulsifying properties, water retention, consistency and textural parameters of heat‐set gels (hardness, cohesiueness, adhesiveness and breaking stress). Textured and fiberized products were tested for hardness, cohesiueness and resistance to shear‐compression both before and after heat treatment.

With powder and paste products, foam stability, emulsifying properties and water retention were generally higher for soybean than for wheat products. Gel forming properties were higher for wheat products. For both raw materials, high correlations were found between different measures of gel hardness, between foam expansion and foam stability, and between emulsification capacity and emulsion stability. With textured products, high correlations were obtained between hardness and resistance to shear‐compression. Products based on wheat were harder and more difficult to shear. As compared to those distributed frozen, textured products distributed dry were significantly lower in cohesiueness following rehydration.
TEXTURE MEASUREMENT OF COOKED RICE AND ITS RELATIONSHIP TO THE EATING QUALITY
Authors: OKABE MOTOO
Published: February 2007

A method has been developed for quantifying hardness, stickiness and cohesiveness of rice. It utilizes the Texturometer and requires only a small quantity of cooked kernels. The portability of rice in Japan is governed by its hardness and the ratio of stickiness to hardness. A texturogram has been constructed showing zones of acceptability as a function of hardness and stickiness. For the non‐glutinous rice to be of high acceptability, the ratio of stickiness to hardness should be between 0.15 and 0.20. The developed testing method and the constructed texturogram were used to demonstrate factors affecting the texture of cooked commodity rice, to describe the textural characteristics of convenience rices and to develop some principles on combining different rice varieties for optimum blend texture.
THE CHEMISTRY OF TEXTURE IN FRUITS AND VEGETABLES
Authors: VAN BUREN J. P.
Published: February 2007

This review is concerned with the chemistry of the major primary cell wall components, pectins, hemicelluloses and cellulose, under conditions found during the normal handling of fruits and vegetables. These polymeric components are considered separately, then their combined changes during maturation, storage and processing are covered. The effects of tissue conditions, pH, enzymes and salt concentrations on the rate and degree of change are discussed. A large part of the review deals with the important texture‐affecting reactions of pectic materials including glycosidic hydrolysis, β‐elimination type depolymerization, demethoxylation, and complex formation.
CORRELATION OF DEFORMATION PROPERTIES WITH SUBJECTIVE HARDNESS OF CHEWING GUM STICKS
Authors: BOGATY H. , TWITTY M. , TALMAGE J. M.
Published: February 2007

A modified deformation theory for the parallel‐plate plastometer, with empirical assumptions that the material obeys the “power law” and that elastic components are negligible, appears to apply to chewing gums of varying degrees of subjective staleness. Data for apparent viscosity correlate with panel perceptions of initial hardness of chew.

Thickness‐time curves generated in plastometer tests can be fitted by either of two different algebraic functions whose constants also reflect the subjective hardness. These equation constants vary in a regular way with changes in the forces employed for deformation so that comparisons under different test conditions are facilitated.
EFFECT OF OTHER HYDROCOLLOIDS ON THE TEXTURE OF KAPPA CARRAGEENAN GELS1
Authors: CHRISTENSEN OTTO , TRUDSOE JENS
Published: February 2007

The effect of different hydrocolloids on the breaking strength, cohesiveness and rigidity of kappa carrageenan gels was studied using comression tests with the Instron. Instrumental measurements were supplemented with benchtop sensory evaluation of texture by mouth, gel clarity and syneresis. The evaluated hydrocolloids included locust bean gum, iota carrageenan, amidated low methoxyl pectin, xanthan gum, and their selected combinations. Best gels were obtained by using 0.15% kappa carrageenan and 0.85% iota carrageenan, or 0.2% kappa carrageenan, 0.2% locust bean gum and 0.6% amidated LM pectin. Although none duplicated the textural quality of gelatine gels, they represented a wide range of interesting and potentially useful textures.
EFFECT OF THERMAL PROCESSING ON STRUCTURE AND RHEOLOGICAL PROPERTIES OF CARRAGEENAN/CAROB GUM GELS
Authors: AINSWORTH P. A. , BLANSHARD J.M.V.
Published: February 2007

Optical rotatory dispersion and rheological studies have been used to investigate changes in carrageenan and carob gels on thermal processing. A synergistic effect was observed on the gel strength of both unprocessed and heat processed carrageenan carob gels when compared to gels without carob, although a lower gel strength was measured after processing. The reduction in strength of gels on heat processing appears to be due mainly to the depolymerisation of the network chains while the crosslinks of the gel are largely unaffected.
CHANGES IN GRAPE FIRMNESS DURING MATURATION
Authors: LEE C. Y. , BOURNE M. C.
Published: February 2007

Puncture force with skin on, puncture force with skin off, deformability, and ˚Brix were measured on six cultivars of grapes grown in northeastern USA as they matured over a six week period. Deformability increased steadily throughout the maturation period. ˚Brix increased rapidly following veraison and then continued to increase at a slow rate. Both puncture forces decreased rapidly at veraison and then continued to decrease at a slower rate. The puncture force with skin on was always much higher than puncture force with skin off. All the physical properties correlated well with each other and with ˚Brix (with a few exceptions). The puncture test with skin on usually gave the highest correlation with ˚Brix. It could probably be used as an alternative test to ˚Brix or as a confirmatory test to supplement the ˚Brix reading.
LIQUID TWO‐PHASE WATER—PROTEIN—POLYSACCHARIDE SYSTEMS AND THEIR PROCESSING INTO TEXTURED PROTEIN PRODUCTS
Authors: ANTONOV YURY A. , GRINBERG VALERY YA. , ZHURAVSKAYA NATALYA A. , TOLSTOGUZOV VLADIMIR B.
Published: February 2007

Conditions for the formation of liquid two‐phase water—protein—polysaccharide systems containing the main classes of proteins, as defined by Osborne, and various acid and neutral polysaccharides have been determined. Phase diagrams of some of these systems have been obtained. It is shown that, proceeding from liquid two‐phase water—protein—polysaccharide systems, one can obtain different protein products without using spinnerets.
A METHOD FOR TESTING THE EASE OF EXTRUSION OF ICING MARKETED IN PLASTIC TUBES1
Authors: VOISEY PETER W. , KLOEK M. , SUMMERS KRISTIN , GILLETTE MARIANNE
Published: February 2007

An instrumental method for evaluating the ease of extrusion of a decorative cake icing marketed in plastic tubes is demonstrated. The force is measured to pull the tube between two rollers to extrude the contents through the tube nozzle or, by increasing the gap between the rollers, to back extrude the contents within the tube. The maximum force, used as a textural indexy correlated with sensory assessments. The instrumental readings were affected by sample temperature, deformation rate and nozzle size and shape so that these conditions must be standardized. The method has potential use in testing a variety of products marketed in tubes.
RHEOLOGICAL PROPERTIES AND APPLICATIONS OF MESQUITE TREE (PROSOPIS JULIFLORA) GUM. 1. RHEOLOGICAL PROPERTIES OF AQUEOUS MESQUITE GUM SOLUTIONS
Authors: CARTER E. J. VERNON , SHERMAN P.
Published: February 2007

The viscosities of aqueous mesquite gum solutions were measured at gum concentrations extending to 16.7% (w/v). Very dilute solutions exhibited typical polyelectrolyte behavior with respect to the influence of gum concentration on the reduced viscosity in the absence and presence of electrolyte. Shear thickening was exhibited at concentrations of 1–16.67% (w/v) when the shear rate exceeded ∼100 s−1, whereas shear thinning was exhibited at lower shear rates. Shear thickening was attributed to configurational changes in the gum molecules at high shear rates. Electrolytes (0.1N NaCl and 0.1N CaCl2) reduced the viscosity of concentrated solutions at high shear rates to a larger extent than increasing the pH. Charge screening by electrolyte permits the gum molecules to assume a more compact configuration.
COMPARISON OF PHYSICAL METHODS FOR ESTIMATING THE MATURITY OF RAW, FROZEN AND COOKED PEAS
Authors: RUTLEDGE P. J. , BOARD P. W.
Published: February 2007

The back extrusion cell, Maturometer, Kramer shear press, FMC Tenderometer, and Ottawa Texture Measuring System wire extrusion cell gave useful estimates of the maturity of raw peas but, two viscosity methods gave unsatisfactory estimates. None of the instruments gave useful estimates of maturity of frozen peas that had been thawed or cooked because blanching conditions and the rate of freezing of the peas affected the readings. The most reliable estimate of raw pea maturity from thawed frozen peas was the alcohol insoluble solids content.
INTERNATIONAL COOPERATIVE COMPARISON OF INSTRUMENT METHODS FOR COOKED RICE TEXTURE
Authors: JULIANO BIENVENIDO O. , PEREZ CONSUELO M. , BARBER SALVADOR , BLAKENEY ANTHONY B. , IWASAKI TETSUY A , SHIBUYA NAOTO , KENEASTER KENNETH K. , CHUNG SOOMI , LAIGNELET BERNARD , LAUNAY B. , DEL MUNDO ANGELITA M. , SUZUKI HIROSHI , SHIKI JUN'ICHI , TSUJI SHOJIRO , YAMA JUNKO TOKO , TATSUMI KYOKO , WEBB BILL D.
Published: February 2007

The texture of 10 milled rices cooked by a standardized method in excess water was measured in 11 laboratories using various instrument methods that had been developed specifically for national samples. The samples selected represented a wide range of rice textures. Instrument indexes for hardness and stickiness of cooked rice generally were more sensitive than the corresponding taste panel scores in discriminating among the 10 cooked rice samples. Instrument indexes for hardness correlated positively among each other as did those for stickiness. Most hardness indexes showed significant negative correlation with stickiness indexes. Most hardness indexes were positively correlated with amylose content whereas stickiness indexes were negatively correlated with amylose content. The continued use of amylose content as an index of eating quality in a rice breeding program is justified.
EVALUATION OF INSTRUMENTAL METHODS FOR FIRMNESS MEASUREMENT OF FRESH AND CANNED CLINGSTONE PEACHES
Authors: SCHWEINGRUBER PETER J. , CARROAD PAUL A. , LEONARD SHERMAN J. , HEIL JULIANNA R. , WOLCOTT TERESA K. , O'MAHONY MICHAEL , WILSON ALFRED
Published: February 2007

The firmness of fresh and canned clingstone peaches was investigated using blade extrusion, back extrusion, and shear‐compression instruments. The three techniques yielded results which correlated well among themselves and to sensory evaluation of peach firmness. Results indicate that high vacuum flame sterilization yields a canned product which is closer in firmness to fresh peaches than is the conventionally retorted product.
TEXTURE MEASUREMENT OF COOKED RICE KERNELS USING THE MULTIPLE‐POINT MENSURATION METHOD 1
Authors: TSUJI SHOJIRO
Published: February 2007

A new modification of Texture Profile Analysis, a two‐point mensuration method, was shown to give better differentiation between different types of cooked rice. The method involves compressing single rice kernels 50% and 90% at 240 mm/mm. Ratios of values obtained at the two compression depths were better reflectors of the texture of rice as affected by the amount of water used in cooking and by rice variety (glutinous versus non‐glutinous). Data are also presented showing how hardness, cohesiveness, adhesiveness and springiness of rice vary with compression or biting depths and with the position of the kernel in the cooker. The ratio of adhesiveness to hardness at 50% compression and the ratio of adhesiveness to hardness between the two compressions were the most useful indices.; in final form February 18, 1981
RHEOLOGY OF GALACTOMANNAN SOLUTIONS: COMPARATIVE STUDY OF GUAR GUM AND LOCUST BEAN GUM
Authors: DOUBLIER J. L. , LAUNAY B.
Published: February 2007

The rheological properties of several samples of guar gum and locust bean gum, characterized by light scattering and intrinsic viscosity measurements, were studied. The flow curves of concentrated solutions were obtained with a cone‐plate viscometer and their viscoelastic properties were measured with a concentric hemispheres viscoelastometer. The two flow‐units Ree‐Eyring model and the Cross equation gave a good fit to the experimental flow curves. The zero shear rate viscosity, and the relaxation time, of the Ree‐Eyring model depend mainly on the reduced concentration c[η]. This result, as well as the viscoelastic properties, indicate that entanglements play a dominant role in concentrated solutions. From a practical viewpoint, it is possible to predict the flow curve of a galactomannan solution at any concentration if the intrinsic viscosity of the sample is known. However, there are secondary differences in the flow parameters, mainly in the relaxation time, which are not ascribed to [η]. It is hypothesized that these differences are due to the mean branching degree rather than to the botanical origin. As, in solution, the smoothest galactomannan macromolecules are more probably aggregated than isolated, further work should aim at establishing the relationships between aggregate formation and degree of branching.
INFLUENCE OF TIME THICKENING ON THE WHIPPABILITY OF CREAMS
Authors: SHIOYA TOSHIAKI , KAKO MASATOSHI , TANEYA SHIN'ICHI , SONE TOSHIMARO
Published: February 2007

Flow properties of creams containing milk fat (Cream A), vegetable fat (Cream C), and vegetable fat plus milk fat (Cream B) were determined with a coaxial cylinder viscometer for a wide range of shear rates. All creams examined showed time thickening. The viscosity increase with shearing time was expressed by two stage equations as follows:

image

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where ηo and ηt are cream viscosity at zero and t shearing time, K1 and K2 are rate constants and C1 and C2 are constants. The first stage (Eq. 1) was assumed to occur in the course of primary clustering of the independent fat globules, and the second stage (Eq. 2) was assumed to occur in the course of coagulation of the fat globule clusters. Both K1 and K2 increased as shear rate increased.

At the same time, the whippability of each cream was determined with a household mixer to which was attached a strain gauge transducer unit for measuring consistency of the whipped creams. There was a tendency for a higher ratio of milk fat/vegetable fat in the creams to decrease the whipping time or to increase whippability of the creams.

Correlations of stability, whippability, and flow properties were examined. A cream which was high stability showed a low K1 value, and a cream which has high whippability showed a high K2 value. K1 and K2 values at a suitable shear rate will be quite helpful in the determination of the physical properties of cream.
FLOW BEHAVIOR OF GUAVA PUREE AS A FUNCTION OF TEMPERATURE AND CONCENTRATION
Authors: VITALI ALFREDO A. , RAO M. A.
Published: February 2007

Flow behavior of guava puree was determined with a tube viscometer. The puree samples (9.8‐16.0° Brix) exhibited shear‐thinning behavior. The flow behavior index of the power law model was nearly constant for all the samples over a temperature range of 25‐60°C; its mean value was 0.43 with a standard deviation of 0.031. The apparent viscosity decreased with increase in temperature and the activation energy offlow was found to be 3.7 kcallg mole. The apparent viscosity increased as the concentration of the purees was increased; the increase was proportional to concentration raised to a power of 2.7. The Mizrahi‐Berk model described well the flow data of the purees. The magnitude of the shear rate exponent was about 0.48, indicating that the purees were suspensions in shearthinning media.
BETWEEN‐SPECIES DIFFERENCES IN FRACTURABILITY LOSS: MICROSCOPIC AND CHEMICAL COMPARISON OF POTATO AND CHINESE WATERCHESTNUT1
Authors: LOH J. , BREENE W. M. , DAVIS E. A.
Published: February 2007

Potato and waterchestnut tissue were used as experimental materials for comparing between‐species differences in heat softening rate. Scanning electron microscope (SEM) techniques were employed to compare cellular and subcellular changes with corresponding fractur ability losses during cooking of potato and Chinese waterchestnut by four cooking methods.

SEM observations strongly suggest that cell wall adhesion and its heat resistance play a major role in fracturability changes during heating. Intracellular substances such as starch and minerals may slightly alter the cell wall strength but do not substantially affect fracturability changes. In addition, differences in the gross chemical composition between species were inadequate for explaining fracturability changes of the two vegetable tissues during heating.