Simultaneous Determination of B₁, B₂, B₃, B₆, B_9, and B₁₂ Vitamins in Premix and Fortified Flour Using HPLC/DAD: Effect of Detection Wavelength: Simultaneous determination of water-soluble B vitamins is a troublesome analytical procedure since they have greatly variable structures and acid-base properties which imposed difficulties on eluting them in short time and selecting wavelength of detection. The aim of the present study was to develop a simple method that overcomes these difficulties. The method was successful in simultaneous determination of B₁, B₂, B₃, B₆, B₉, and B₁₂ in premix and fortified flour by extracting vitamins with 0.1 (w/v) of ascorbate and ethylene diamine tetra-acetic acid (EDTA) solution followed by eluting using gradient mobile phase consisting of 0.03 trifluoroacetic acid aqueous solution (pH 2.6) and acetonitrile on high performance liquid chromatography (HPLC) instrument coupled with diode array detector (DAD). Elution of vitamins was completed within 9.3min, and the lowest values obtained for limit of quantification (LOQ) for B₁, B₂, B₃, B₆, B₉, and B₁₂ were 0.6, 0.2, 0.8, 0.3, 0.5, and 0.7μg/mL, respectively, at four wavelengths of 361, 280, 265, and 210nm. In general, variation of wavelength of detection in the range from 210 to 361nm affects sensitivity but had a marginal effect on the linearity and LOQ of the developed method and its application for determining B vitamins in premix and fortified flour. The 210nm wavelength exhibited the highest sensitivity though resulted in higher values of B vitamins in fortified flour with respect to 265, 280, and 361nm. Noteworthy, determination of B₂ and B₁₂ in the premix at 361nm had relatively high RSD values compared to the lower wavelengths. Thus, wavelengths in the range from 265 to 280 may be more favorable over 210 and 361nm. The method reported in the present work does not require any sample cleanup/preconcentration steps, and chromatographic elution was achieved in 9.3min without the need for ion-pairing reagents.

In conventional practice, the Poolish preferment is typically equal weights (1:1) of flour and water fermented with commercial yeast for 24 h. However, this investigation employs the preparation of Poolish preferments subjected to four fermentation durations (24, 48, 72, and 96 h) using the backslopping technique and incorporating them into the Arabic bread recipe at different levels (20%, 30%, and 40%) as a substitution for commercial yeast to systematically evaluate their effects on the textural attributes and vitamin retention of Arabic flatbread. Poolish addition altered amylose and amylopectin ratios and increased the amylopectin content, optimized the rheological properties, yielded a softer texture, and extended the shelf life of the produced bread. Vitamin analysis of Poolish bread samples showed that B1 and B6 were less stable than B3 and B9 due to their heat/acid sensitivity. The investigation found that the 24‐h Poolish, incorporated at 20% and 30% substitution levels, offered the optimal balance between high B‐vitamin retention and improved technological performance. The findings highlight the importance of integrating Poolish dough (PD) into the Arabic bread industry, as it boosts nutritional value and improves staling resistance.