Detecting wheat flour adulteration by portable infrared and Raman spectroscopies

• Wheat flour fraud risk is rising during global disruptions like the war in Ukraine. • Portable Raman and IR detected wheat flour adulteration with potato and corn flour. • IR had a 6.9% detection limit, while Raman showed a higher limit of 22.6%. • Portable vibrational spectroscopy offers rapid, non-destructive detection of flour fraud. Monitoring wheat flour fraud is vital, especially during global disruptions like the war in Ukraine, which heighten the risk of economically motivated adulteration. This study explores the use of portable Raman and infrared (IR) spectroscopy to detect wheat flour adulteration with potato and corn flour. Principal Component Analysis (PCA) revealed spectral differences, while Partial Least Squares Regression (PLSR) models quantified adulterant levels. Both techniques successfully identified adulteration, with typical errors of prediction for test samples of 4-5% for infrared and 8.7-10.6% for Raman spectroscopy. In addition, IR achieved a limit of detection (LOD) as low as 6.9% and Raman 22.6%. The findings highlight portable vibrational spectroscopy as a rapid, non-destructive tool for detecting flour fraud, supporting food quality control and regulatory enforcement