摘要:

ABSTRACTWell‐defined measurements of the mechanical properties of food and the reduction of sensory attributes to the fundamental primary entities, together with the definition of their correlation functions, provide the basis for the eventual development of instruments calibrated in terms of human sensory response and having a high probability of predicting the consumer reaction. Since mechanical measurements of most foods are time‐dependent, the understanding of conditions prevailing during sensory testing (rate of shear, etc.) will aid in selecting the optimum conditions for instrumental testing. Recent progress in this area has been made with fluids and some solid foods. The method of magnitude estimation assists the researcher in discovering the underlying laws relating physical product changes to perceived textural changes. At the same time, magnitude estimation also aids the product developer to determine empirical, ad hoc relations between physical levels of mechanical variables and textural perceptions, even if the true, underlying relationships are not known. Ad hoc equations can be used (in conjunction with optimization techniques) to determine the combination of mechanical variables that (a) produce a specific sensow texture profile, and (b) maximize texture/product acceptabil

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01214.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThe influence of slit width on the force deformation curves obtained for raw and cooked meat of different myofibrillar contraction states was investigated with a modified version of the Warner‐Bratzler (WB) shear device. Decreasing the clearance or compressing the sample directly onto a base plate (i.e. no slit) had little effect on the initial yield force values. Meat samples retained most of their original tensile strength after compression to initial yield on the shear device. Even cold‐shortened cooked samples compressed to peak force values retained over 30% of their original tensile strength.Peak tensile and peak WB shear force measurements were highly correlated: R2= 0.71, 0.94 and 0.88for raw, stretched/cooked and contracted/cooked samples, respectively. The slopes (WB on tensile) of the regression lines were increased by both cooking and by contraction to below rest length. These results indicate that components other than tensile in the WB shear force measurements were increased by cooking and by myofibrillar contract

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01215.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThe effects were studied of low concentrations of 5 selected hydrocolloids (xanthan, hydroxypropylcellulose, sodium alginate, and carboxymethylcellulose of low and medium viscosity types) on viscosity and sensory properties of 3 commercial beverages: tomato juice, orange drink and soluble coffee. Tomato juice and orange drink were tested at 0° and 22°C, while coffee was tested at 22° and 60°C by 11‐14 highly trained judges. Apparent physical viscosity was determined with a Brookfield uiscometer. Due to precipitate formation, it was not possible to test sodium alginate in orange drink nor hydroxypropylcellulose in coffee at 60°C.Without exception, increasing the hydrocolloid concentration significantly depressed (P0.9) were obtained between sensory and physical visco

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01216.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThe brittleness and crispness of low moisture foods and the crispness of selected high moisture foods were evaluated both instrumentally by Instron fracture tests and using a sensory panel. Brittleness was evaluated sensorially during the “first bite” whereas crispness was identified at a later stage of mastication. The maximum force at fracture of low moisture foods correlated inversely with panelists’ evaluations of brittleness either in the mouth or using the fingers. Panelists' evaluations of crispness in the mouth correlated reasonably well with the initial linear portion of the Instron force‐deformation curves when the sample were supported near their ends and also in their middle regions. The shapes of the force‐deformation curves for high moisture foods were very much influenced by the way in which samples were supported in fracture tests, the method of fracture and the Instron cross

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01217.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThe mechanical properties of Satsuma oranges were studied under static, quasi‐static and impact loading in order to determine conditions leading to minimum fruit injury in containerized shipping. The results indicated that the use of containers is safe for a 70h transport provided the stacking height does not exceed 70 cm. The static load at the bottom of the container should not exceed 2 kg per fruit if permanent deformation is to be avoided; the fruit ruptures when the load exceeds 4.2 kg per fruit. The time‐deformation curve under static load was explained with a Burgers model modified with a sliding element. Bruising energy by impact was 3 times and that by quasi‐static loading 1.4 times as great as that by static loading. The relationship between impact acceleration and dropping height of single fruits agreed well with the Hertz’ theory of colliding spheres for dropping heights up t

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01218.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThe 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 t

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01219.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

General Principles: Viscoelastic Properties of Plant Cell Walls I. Mathematical Formulation for Stress Relaxation with Consideration for Pre‐Extension Rate. S. Fujihara, R. Yamamoto and Y. Masuda (Sci. Ed. Inst. of Sakai City, Mozu ak ah ata, Sakai 591, and Dept. of Biology, Faculty of Sci., Osaka City Univ., Sumi‐yoshi‐ku, Osaka 558, Japan) Biorheology15, (1978) 63–75.General Principles: II. Effect of Pre‐Extension Rate on Stress Relaxation, ibid. 77–85.General Principles: III. Hysteresis Loop in the stress‐Strain Curve at Constant Strain Rate. Y. Masuda (Dept. of Biology, Faculty of Sci., Osaka City Univ., Sumiy oshi‐ku, Osaka 558, Japan), ibid. 87–97.General Principles: Rheology of Polyelectrolyte‐Stabilized Emulsions. II. Dynamic Measurements. T. Van Vliet, J. Lyklema and M. van den Tempel (Lab. for Phys.&Colloid Chem., Agric. Univ., de Dreyen 6 Wageningen, The Netherlands). J. Colloid and Interface Sci.65, (1978) 505–508.General Principles: Evaluating the Caking Strength of Powders. T. Tanaka (Dept. of Chemical Process Engineering, Hokkaido Univ., Sapporo, Japan). Ind. Eng. Chem. Prod. Res. Dev.,17, (1978) 241–246.General Principles: Dynamics of Insoluble Monolayers. I. Dilational or Elastic Modulus, Friction Coefficient and Marangoni Effect for Dipalmitoyl Lecithin Monolayers. D. S. Dimitrov, I. Panaiotov, P. Richmond and L. Ter‐Minassian‐Saraga (last author's address, Laboratoire de Physico‐Chimie des Surfaces et des Membranes, UER Biomedicale, 45 me des Saints Peres, 75270 Paris Cedex 06, France). J. Colloid and Interface Sci.65, (1978) 483–494.General Principles: Measuring the Texture of Cooked Spaghetti. I. Sensory and Instrumental Evaluation of Firmness. P. W. Voisey, E. Larmond and R. J. Wasik (Res. Branch, Agric. Canada, Ottawa, Ontario K1A OC6). Can Inst. Food Sci. Technol. J. 11, (1978) 142–148.General Principles: Laboratory Measurements of Eggshell Strength. I. An Instrument for Measuring Shell Strength by Quasi‐Static Compression, Puncture and Non‐Destructive Deformation. P. W. Voisey and D. C. MacDonald (Eng. Res. Service, Res. Branch, Agriculture Canada, Ottawa, Ontario K1A OC6. Canada) Poultry Sci.57, (1978) 860–869.General Principles: Milk Gel Structure VIII. Effect of Drying on the Scanning Electron Microscopy of Some Dairy Products. M. Kalab (Food Research Inst., Research Branch, Agriculture Canada, Ontario, Canada K1A OC6) Milch wissenschaft33, (1978) 353–358.General Principles: Texture‐Structure Relationships in Texturized Soy Protein. III. Textural Evaluation of Extruded Products. T. J. Maurice, L. D. Burgess and D. W. Stanley (Dept. of Food Science, Univ. of Guelph, Guelph, Ontario, Canada). Can. Inst. Food Sci. Technol. J.9, (1976) 173–176.General Principles: Texture‐Structure Relationships in Texturized Soy Protein. IV. Influence of Process Variables on Extrusion Texturization. T. J. Maurice and D. W. Stanley (Dept. of Food Science, Univ. of Guelph, Guelph, Ontario, Canada) Can. Inst. Food Sci. Technol. J.11, (1978)1–6.General Principles: Studies of Some Properties of Milk/Soymilk Mixture. W. M. Abou El‐Ella, S. M. Farahat and M. A. Ghandour (Dept. of Food Science, Ain Shams and Zagazig Univ., Egypt) Milch wissenschaft33, (1978) 295–297.General Principles: Differences in Baking Quality Between Wheat Flours. F. MacRitchie (CSIRO Wheat Research Unit, North Ryde, NSW

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01220.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1978.tb01213.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY