Determination of the staling rate of Egyptian Balady bread by using Texture Profile Analysis (TPA): A new method.

Document Type : Original Article

Authors

1 Bread and Pasta Dep., Food Technology Research Institute, Agricultural Research Center

2 Food Technology Research Institute, Agricultural Research Center, Giza, Egypt.

Abstract

Texture profile analysis (TPA) was conducted on seventy balady bread samples collected from different five Egyptian governorates (i.e. Cairo, Giza, Beheira, Sharkia and Beni Suef) with the aim of developing a new and fast method to assess the staling of the Egyptian flat balady bread as a function of different TPA parameters. Results obtained from the TPA were compared against the classical Alkaline Water Retention Capacity (AWRC) method of bread staling determination over a storage period of three days. Hardness, adhesiveness, resilience and chewiness were found to increase as the storage period of bread samples increased, while cohesiveness decreased with the storage. The obtained results of TPA showed that among different TPA parameters, hardness, adhesiveness, cohesiveness and chewiness were highly correlated with the staling rate (SR) during a three days storage period with values of correlation coefficients ranging from 0.821 to 0.973, while other TPA parameters (i.e. gumminess, resilience and springiness) were weakly correlated with the staling rate. Moreover, moisture content was linearly decreased as the storage of bread increased from 36.78 at the zero time to 33.19% at the third day. Derived mathematical models to calculate the AWRC and SR were significant and of the linear type with moisture content, time (day), hardness, cohesiveness, adhesiveness and chewiness as independent variables, with reasonable adjusted R2 ( 0.55 and 0.41), and adequate precision values (31.57 and 18.68) for AWRC and SR, respectively . Validation of the new method, as assessed by t-test, showed that the differences between AWRC and SR values obtained by our method were not significantly different (P<0.05) from those of their counterparts obtained by the classical AWRC method at the different storage times of bread. Our new method can be used as an alternative to the classical AWRC method with reliable, fast and accurate calculated values of both AWRC and SR.

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