摘要:

AbstractAn engineering approach to evaluation of mechanical attributes of texture in solid food materials is presented. The usefulness of such an approach, which is based on sound physical principles, is discussed. An illustrated list of mechanical tests applicable to solid food materials is given along with formulas for computing the mechanical properties which should be related to mechanical attributes of texture. Examples of previous work which have employed these techniques with the intention of correlating the results with some textural parameters of solid foods are reviewed. It is shown that these objective physical measurements have proven to be useful and give more fundamental data than most of the conventional, poorly defined tests employed in the past. The use of these techniques, where applicable, for future studies is recommended.

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00719.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractA coaxial‐cylinder viscometer with novel drive, control, and recording features was developed. It is capable of measuring many of the rheological properties of fluid systems over a wide range of viscosities and shear rates. The instrument is load‐independent and thermostatically controlled, and has good frequency response. The viscometer can be driven according to a variety of input wave forms either unidirectionally or in an oscillatory mode about zero with the output fed into anX‐Yrecorder. A continuous shear rate/shear stress flow curve can be obtained in less than 3

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00720.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractAs part of a programme of investigation into the effects of processing on the texture of food the General Foods Texturometer was adopted, because it appeared to offer versatility, multiple‐property determination and a fair degree of objectivity.Preliminary investigations with the instrument indicated a high degree of reproducibility when used on a ‘recoverable’ material (rubber). The results are highly dependent on the dimensions of the sample and reproducibility decreases somewhat with increasing hardness of material under test. The ‘representativeness’ of the results for a range of food materials varied widely, being influenced by the uniformity of the material and the accuracy with which samples can be prepared.Experiments to correlate the results from this instrument with those from the Instron Universal Testing Machine, the Kramer Shear Press and a subjective panel method indicate that the Texturometer ‘hardness’ might prove the most useful measure of the firmness/hardness of foods as judged subjectively. None of the other textural properties measured by the Texturometer in this work proved of value in indicating subjective textural characteristics and further study of such properties is currentl

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00721.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractShear and compression strengths of individual carrots were measured with the Instron Universal Testing Machine. Compression correlated highly, but shear poorly, with sensory hardness as judged by compressing and flexing. The study confirmed the usefullness of the coefficient of compression in predicting textural quality of carrots.

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00722.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractCreep compliance‐time studies at low stresses give more information about the structural changes in work softened butter and margarine than the Cone Penetrometer. They show that margarine undergoes a greater structural change than butter. Margarine loses most of its instantaneous elasticity in an unrecoverable manner. However, most of the Newtonian viscosity loss is recovered. Butter loses much less of its instantaneous elasticity, and most of what is lost is recovered during aging, but less of the Newtonian viscosity which is lost is recovered. Retardation spectra derived from creep compliance‐time curves for both butter and margarine before work softening show a peak at ∼104sec. In contrast to margarine, butter does not lose this peak when work‐softened. For margarine, the peak slowly redevelops during aging and occurs at ∼102sec. Past interpretation of Cone Penetrometer data has been based on the simplified concept of primary irreversible bonds and secondary reversible bonds, and the changes in their relative proportions during work softening. The present approach avoids the allocation of bond strengths into these arbitrary categories, and is based on the realization that butter and margarine contain a wide range of bond

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00723.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractThe viscosities of fat crystals extracted by 1 % Aerosol O.T. from butter and margarine have been studied using a Weissenberg Rheogoniometer. By applying the Brodnyan (1959) equation for non‐spherical particles to the viscosity data at high rates of shear, after correcting for secondary flow phenomena, it was deduced that the axial ratios of the margarine fat crystals were between 3.05 and 3.94, with the fat crystals from butter lying midway between the two extremes. By applying viscosity equations of the exponential type to such data, it should be possible to calculate the viscosity of butter and margarine at very high rates of shear when the viscosity of the liquid oil in the fat phase and the volume concentration of water drops are known. This information could be useful for predicting the spreadability characteristics of butter and margarin

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00724.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractThe white muscle of the Sacramento blackfish (Orthodon microlepidotus) was processed by freezing, dehydration, and cooking. Myosin was extracted immediately afterwards or following a period of storage in order to examine evidence for denaturation. The tests used were the solubility of whole muscle protein and the intrinsic viscosity, isoelectric point, ATPase activity, ultra‐violet absorption spectrum, and optical rotatory dispersion of purified myosin extract. Almost all measures used showed that denaturation increased in the order: fresh

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00725.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractAn empirical measure of viscosity, which is often far from being a linear function of composition, was used together with refractive index to build up a function which bears a linear relationship to the composition of tomato paste‐water‐sucrose mixtures. The new function can be used directly for rapid composition control by linear vector‐vector transform

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00726.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00727.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

Aidvances in Oral‐Physiology(edited by Yojiro Kawamura, Osaka Universit

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1970.tb00728.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY