Assessing the Level of Adulteration in Firik Bulgur Mixed with Regular Bulgur by Using a Color Meter: A Preliminary Study

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  • Muharrem Keskin Hatay Mustafa Kemal University



Bulgur, food fraud, color meter, correlation, regression


Firik bulgur is produced by a different method than regular bulgur and is more nutritious but it is three to four times more expensive than normal bulgur. Adulteration is common by mixing normal bulgur to firik bulgur. It is impossible to determine the adulteration level by human eye. In this work, the possibility of detecting the ratio of regular bulgur in the adulterated (mixed) firik bulgur was studied. Two different data sets (DS1 and DS2) were prepared with two different brands of firik bulgur mixed with normal bulgur (mix ratio: from 0 to 100% with increments of 2.5%). Colors of the mixture samples were quantified by using a color meter by two color models (L*a*b* and L*C*h). Correlation and regression analyses were applied. Half of the data (n=41) was used for calibration and the other half (n=41) for validation in the regression analysis. It was found that the normal bulgur ratio in the mixture could be estimated from color data. A slightly better prediction performance was obtained in the DS2 data set (RMSEP=12%; R2=0.83) compared to the DS1 data set (RMSEP=19%; R2=0.57). In sum, a chromameter offers promising results to estimate the ratio of regular bulgur in the adulterated firik bulgur with reasonable accuracy (R2=0.83).


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