The dependence of peleg's coefficients on selected conditions of a relaxation test in model samples of edam cheese

Abstract

The first aim of this work was to compare the influence of using two probes (a 100-mm plate and a 5-mm spherical probe) during a compression test on the trends of hardness changes during ripening of Edam cheese. Both of the above-mentioned probes were also applied in relaxation tests for a relaxation time of 30-300s (10 arbitrary times were used). By means of Peleg's model, the values of a parameter (the extent of material relaxation) and b parameter (the initial rate at which the stress relaxes) were calculated. Moreover, the values of a and b parameters, obtained during 10 different relaxation times of the probe after reaching the maximum deformation of the sample (30-300s), were compared (calculated on the basis of Peleg's model). Edam cheese during ripening (1-84 days) was used as a model product. The values of cheese hardness within the ripening period (determined by means of both of the above-mentioned probes) strongly correlated among themselves and also with the sensorially evaluated rigidity. Only a parameter was able to provide an adequate description of the actual changes in cheese within the ripening period but only at a relaxation time of ≤120s (after reaching the maximum deformation of the sample; valid for both probes tested). Longer relaxation times do not provide a relevant description of the changes in cheese texture during ripening. B parameter provided no relevant description of the changes in cheese during ripening in any of the relaxation times studied (concerning both probes). © 2013 Wiley Periodicals, Inc.