Application of Near Infrared Transmission for the Determination of Ash in Wheat Flour

Near infrared transmission (NIT) spectroscopy was investigated for applicability as a rapid screening tool to evaluate ash content in wheat flour. Ash content in fl our samples was determined also by reference method. One hundred thirteen wheat fl our samples with ash content of 0.367-0.964% were collected from the Belje,d.d., PC Mlin and PPK Valpovo, and used for this study. Infratec 1241 Grain Analyzer Flour Module that comes with ready-touse calibrations, was used to obtain transmission spectra of wheat fl our. All measured ash values obtained by NIT method were within calibration limits (0.00-1.10) of the instrument. Simple linear regression analyses showed high significant correlation between the NIT and the reference method (r=0.953). The NIT results were not accurate enough for all flour types when compared to the results obtained by the reference method. Only the results for fl our types 400 and 550 indicate sufficient accuracy for fl our type evaluation. Considering its advantages over standard methods, including its recalibration, NIT could represent a good tool for evaluation of all fl our types in the future, as it is used for protein and moisture determination in wheat grain today