摘要:

ABSTRACTA three‐parameter constitutive relationship was developed based on a strain energy function to describe the mechanical behaviour of gels subjected to large deformation under compressive load. The parameters in the relationship can be estimated from experimental data using regression techniques. Alternatively, these unknowns may be determined directly from three compression parameters σm, ɛm, β, which represent the strength, ductility and nonlinearity of the mechanical behaviour, respectively. The new constitutive relationship fits experimental data, for both brittle and ductile gels, up to the point of compressive fai

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01282.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTThree brands of instant coffee were used as model agglomerated powders. They were exposed to compaction in a tap density tester. Experiments were done confining samples of instant coffee in graduated cylinders with several diameters, i.e., 1.6, 2.0 and 2.4 cm; and different product heights, i.e., 3.2, 6.3, and 12.5 cm. Increased attrition was noticed with the number of tappings, which ranged from 0 to 10,000 taps. Changes in bulk density were fitted to two‐parameter models used for compaction of food powders, using nonlinear regression. New three and four‐parameter models were proposed, and their fit to experimental data was also examined. The fit of these new models was better than that of previous ones, indicating that the combined effect of attrition and compaction cannot be properly described by models containing less than three parameters. The container diameter, product height, and particle size were found to affect the parameters’ estimates for the models exa

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01283.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

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 oyvalues, 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 oyvalues. 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 pur

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01284.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTFoaming properties of three different protein solutions [casein ca, soybean isolate si, deamidated gluten dg] were studied. A video image camera, coupled to an apparatus designed for the study of the formation and the stability of foams, made it possible to follow the evolution of the foam textures at the same time as physical characteristics, such as the foam volume and the liquid in the foam. The texture of the images was characterized by an original mathematical procedure derived from the two‐dimensional Haar transform. A principal component analysis was then applied to the assessed texture characteristics, in order to emphasize the similarities and the differences between the foam textures. Video image analysis was found to be complementary to the physical characterization of the foams. According to the regularity and the stability of their foams, the proteins could be ranked in the following order (from the more to the less stable foams): ca, dg, s

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01285.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTA sensitive and inexpensive penetrometer is described, consisting of a mounted rod and polished steel ball that may be advanced downward at variable speed through meat slices mounted on a plexiglass cylinder. The slice + mounting cylinder was placed on a top‐loading balance, tared to zero, and centered under the penetrometer rod. Bind strength was measured as the peak force (g) required for the steel ball advancing at 2.0 cm/min to penetrate the meat slice. Data points (grams force versus time) were collected and plotted using an IBM‐compatible personal computer and printer. Since the balance collected gram values continuously, a QuickBasic program was developed, allowing the user to specify the time interval (1,2,5 s, etc.) between recorded values. Bind strength of turkey rolls was increased by finely chopping the emulsion (vs. coarsely‐ground samples), and by inclusion of 3% nonfat dry milk. Whey protein concentrate (3%) increased bind strength of finely chopped, but not coarsely ground

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01286.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTThe effects of protein and salt concentrations, anions, and heating on thejlow properties of oat globulin dispersions were studied. Flow properries were greatly influenced by the conformation and state of aggregation‐dissociation of the oat protein polypeptides. Chemical modijications including deamidation, acylation, trypsin hydrolysis and linoleate treatment also change the flow characteristics of oat protein concentrates and isolate

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01287.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTThe rheological properties of heat whey protein concentrate gels were studied by dynamic oscillation rheometry. A whey protein concentrate of 75% protein was used to make solutions of 10.3, 12.5 and 14.5% protein (w/w), which were heated to 90C for gel formation. Specific attention was focused on the temperature dependence of the mechanical properties of the gels during cooling and reheating. In all cases the magnitude of the complex modulus |G*| was found to increase with decreasing temperatures from 90 to 30C. The tan δ, which is related to the relative viscoelasticity of the gels, increased with decreasing temperatures from 90 to 60C. At temperatures between 60 and 30° C, tan δ remained constant. The dependence of |G*| and tan δ on temperature was found to remain constant during heating and cooling between 30 and 70C, indicating that rheological changes were reversible within this temperature ra

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01288.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Book Reviewed in this Article:FEEDING AND THE TEXTURE OF FOOD. J.F.V. Vincent and P.J. Lillford, eds.OAT BRAN. P.J. Wood, ed.

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01289.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

GENERAL PRINCIPLES: A Comparison of the Rheological Characteristics of Different Fractions of Chicken Myofibrillar Proteins.Y.L. XiongGENERAL PRINCIPLES: Bacterial Cellulose. III. Development of a New Form of Cellulose.A. Okiyama, M. Motoki and S. YamanakaGENERAL PRINCIPLES: Ifeat Capncity of Hydrated and Dehydrated Globular Proteins: Denaturation Increment of Heat Capacity.I.V. Sochava and 0.1. SmirnovaGENERAL PRINCIPLES: Adsorbed Films of β‐Lactoglobulin + Lecithin at the Hydrocarbon‐Water and Triglyceride‐Water Interfaces.E. Dickinson and G. IvesonGENERAL PRINCIPLES: The Effect of Gamma Irradiation on Guar Gum, Locust Bean Gum, Gum Tragacanth and Gum Karaya.K. King and R. GrayGENERAL PRINCIPLES: The Existence of Static Yield Stresses in Suspensions Containing Noncolloidal Particles.D.N. Husband, N. Aksel and W. GleissleGENERAL PRINCIPLES: Bread Crumb Amylograph Studies. I. Effects of Storage Time, Shortening, Flour Lipids and Surfactants.A. Xu, O.K. Chung and J.G. Ponte, Jr.GENERAL PRINCIPLES: Bread Crumb Amylograph Studies. 11. Cause of Unique Properties.A. Xu, J.G. Ponte, Jr. and O.K. ChungGENERAL PRINCIPLES: Differential Scanning Calorimetric and Rheological Study of the Gelatinization of Starch Granules Embedded in a Gel Matrix.H. Liu and J. LelievreMETHODOLOGY AND INSTRUMENTATION: Mathematical Analysis of Variation of Density and Viscosity of Apple Juice with Temperature and Concentration.L. BayindirliMETHODOLOGY AND INSTRUMENTATION: A Single Kernel Creep and Recovery Test.S. Cenkowski, J. Bielewicz and M.G. BrittonMETHODOLOGY AND INSTRUMENTATION: Mechanical Thumb Sensor for Fruit and Vegetable Sorting.A. Mizrach, D. Nahir and B. RonenMETHODOLOGY AND INSTRUMENTATION: Measurement of Very Low Strains Using a Stress Rheometer: A New Rotation Sensing Transducer (RST).A. Magnin and J.M. PiauMETHODOLOGY AND INSTRUMENTATION: A Spinning Drop Tensioextensometer.D.D. Joseph, M.S. Amey, G. Gilberg, H. Hu, D. Hultman, C. Verdier and T.M. VinagreMETHODOLOGY AND INSTRUMENTATION: Rotational Viscometry Under Presence of Apparent Wall Slip.O. Wein and V.V. TovchigrechkoMETHODOLOGY AND INSTRUMENTATION: Description of the Textural Appearance of Bread Crumbs by Video Image Analysis.D. Bertrand, C. Le Guerneve, D. Marion, M.F. Devaux and P. RobertMETHODOLOGY AND INSTRUMENTATION: Use of a Penetrometer for Measuring Rheological Characteristics of Biscuit Dough.R.S. Manohar and P.H. RaoINSTRUMENTAL MEASUREMENTS: Linear Viscoelastic Behavior of Commercial and Model Mayonnaise.C. Gallegos, M. BerjanoINSTRUMENTAL MEASUREMENTS: Elastic Properties of Bread Crumb (Research Note).A. Nussinovitch, M.S. Steffens and P. ChinachotiINSTRUMENTAL MEASUREMENTS: Relationship Between Rheological Properties and Composition of Swiss‐Type Cheese. 1. Multiple Regression Analysis.H. Rohm, H. Lederer and W. GinzingerINSTRUMENTAL MEASUREMENTS: Physiochemical and Rheological Characterization of Sorghum Starch (Research Note).M. Carcea, R. Cubadda and R. AcquisticciINSTRUMENTAL MEASUREMENTS: Measurement of Firmness in Carrot Tissue During Cooking Using Dynamic, Static and Sensory Tests.S.V. Ramana. C.J. Wright and A.J. TaylorINSTRUMENTAL METHODS: Development of a Method to Measure Rheological Properties of Carrot Cell and Cell‐Wall Materials.S.V. Ramana and A.J. TaylorCORRELATING INSTRUMENTAL&SENSORY MEASUREMENT: Physical, Chemical and Sensory Characteristics of Japanese‐Type Plums Grown in Georgia and Alabama.J.A. Robertson, F.I. Meredith and S.D. Senter, W.R. Okie, and J.D. NortonCORRELATING INSTRUMENTAL&SENSORY MEASUREMENT: Texture and Eating Quality of Raw‐ and Thawed‐Roasted Turkey and Chicken Breasts as Influenced by Age of Birds and Period of Frozen Storage.S.O. Awonorin and J.A. AyoadeSENSORY ASSESSMENT: Sensory Profiling of Duke de Leche, a Dairy Based Confectionary Product.G. Hough, N. Bratchell and D.B. MacdougallSENSORY ASSESSMENT: Free‐Choice Profiling of Milks and Other Products Prepared with Milks of Different Fat Content.M.M. Raats and R. ShepherdSENSORY ASSESSMENT: A Statistical Appraisal of the Problem of Sensory Measurement.C. Gay and R. MeadSENSORY ASSESSMENT: Performance Assessment of Sensory Panelists.P. A. Pritchett ManganSENSORY ASSESSMENT: Influence of Oat Gum, Guar Gum and Carboxymethyl Cellulose on the Perception of Sweetness and Flavour.Y. Malkki, R.‐L. Heinio and K. AutioSENSORY ASSESSMENT: Optimizing Texture of Reduced‐Calorie Yellow Layer Cakes.A.M. Frye and C.S. SetserFACTORS AFFECTING TEXTURE: Does Phytic Acid Influence Cooking Rate in Common Beans?I. Bernal‐Lugo, A. Castillo, F. Diaz De Leon, E. Moreno and J. RamirezFACTORS AFFECTING TEXTURE: Postharvest Changes in Pectic Substances in Chilled Peaches.Cantor, S., Meredith, F.I. and Wicker, L.FACTORS AFFECTING TEXTURE: Relationships Between Soybean Components and Tofu Texture.M.J. Schaeffer and J. LoveFACTORS AFFECTING TEXTURE: Peach Vibration Bruising: The Effect of Paper and Plastic Films Between Peaches.P.J. Vergano, R.F. Testin, A.C. Choudhari and W.C. Newall, Jr.FACTORS AFFECTING TEXTURE: Effects of Lipoxygenase and Yeast on the Rheological Properties of Dough.C.L. Kerr, J.M. Faubion and R.C. HoseneyFACTORS AFFECTING TEXTURE: Sensory and Textural Characteristics of Rice Flour and Mechanically Deboned Turkey Extrudates.N.C. Flores, A.D. Clarke, H. Heymann and F.‐H. HsiehFACTORS AFFECTING TEXTURE: Evaluation of the Tenderness of Beef Top Sirloin Steaks.J.J. Harris, R.K. Miller, J.W. Savell, H.R. Cross and I.J. RingerFACTORS AFFECTING TEXTURE: Rheological and Water‐Holding Properties of Comminuted Turkey Breast and Thigh: Effect of Initial pH.D.L. Daum‐Thunberg, E.A. Foegeding and H.R. Ball, Jr.FACTORS AFFECTING TEXTURE: Retarding Vegetable Softening by Cold Alkaline Pectin Deesterification Before Cooking (Research Note).J.P. Van Buren and L.A. PitiferFACTORS AFFECTING TEXTURE: Texture and Rehydration of Dehydrated Carrots as Affected by Low Temperature Blanching.A. Quintero‐Ramos, M.C. Bourne and A. Anzaldua‐MoralesFACTORS AFFECTING TEXTURE: Hard‐to‐Cook Defect in Cowpeas: Storage‐Induced and Treatment‐Induced Development.K. Liu. D. Phillips, Y.‐C. Hung, R.L. Shewfelt and K.H. McWattersFACTORS AFFECTING TEXTURE: Extrudate Cell Structure‐Texture Relationships.A.H. Barrett and M. PelegFACTORS AFFECTING TEXTURE: Relationships of Hydrophobicity and Antigenic Activity to Fat‐Binding Capacity of Heat Denatured Meat Proteins.M.L. Marin, D. Selgas, C. Pin and C. CasasFACTORS AFFECTING TEXTURE: Firming of Bread Crumb with Cross‐Linked Waxy Barley Starch Substituted for Wheat Starch.T. Inagaki and P.A. SeibFACTORS AFFECTING TEXTURE: The Journal of Food Engineering, Vol. 16 (1992), published in Great Britain by Elsevier Science Publishers, Ltd., contains a special issue devoted to Rheology of Foods and edited by R.P. Borwankar and C.F. Shoemaker IIIFACTORS AFFECTING TEXTURE: Food Texture and Rheology: A Tutorial Review.R.P. BorwankarFACTORS AFFECTING TEXTURE: Measurement of Thixotropy of Model Food Colloidal Suspensions with Step Change Shear Range.J.I. Amemiya and C.F. ShoemakerFACTORS AFFECTING TEXTURE: Failure Testing of Gellan Gels.J. Lelievre, I.A. Mirza and M.A. TungFACTORS AFFECTING TEXTURE: Thermorheological Studies of Food Polymer Dispersions.S.R. Owen, M. A. Tung and A.T. PaulsonFACTORS AFFECTING TEXTURE: Rheological Characterization of Melting of Margarines and Tablespreads.R.P. Borwankar, L.A. Frye, A.E. Blaurock and F.J. SasevichFACTORS AFFECTING TEXTURE: The Effect of Shear Rate and Strain on the Pasting Behavior of Food Starches.J. LohFACTORS AFFECTING TEXTURE: Comparison of Small and Large Deformation Measurements to Characterize the Rheology of Wheat Flour Doughs.J.I. Amemiya and J.A. MenjivarFACTORS AFFECTING TEXTURE: Flow Profiles in a Tube Rheometer Using Magnetic Resonance Imaging.K.L. McCarthy, R.J. Kauten, M.J. McCarthy and J.F. SteffeFACTORS AFFECTING TEXTURE: Use of an Ultrasonic Technique to Evaluate the Rheological Properties of Cheese and Dough.H.O. Lee, H. Luan and D.G. DautFACTORS AFFECTING TEXTURE: Calibration o

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1993.tb01290.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY