Evaluation of near infrared spectroscopy for direct detection of common microplastics contamination in camel Milk powder.

MPs contamination in food products, particularly high-value dairy powders, poses emerging health and quality concerns. This study evaluates NIR spectroscopy as a rapid, non-destructive tool for direct detection and quantification of typical MPs (PE, PP, PS, and PET) in camel milk powder. A total of 240 spiked samples (0.01-1.00% w/w) were prepared and analyzed using Fourier-transform NIR spectroscopy. PCA revealed distinct spectral clustering between uncontaminated and MPs spiked samples, with separation driven by NH and CH vibrational bands. PLS-DA models, optimized with GLSW preprocessing, achieved high classification accuracy for both uncontaminated samples (classification error of 0.004) and individual MP types (classification errors from 0.008 to 0.026). PLS models showed strong performance for PP and PS (R2CV = 0.789 and 0.798, respectively), though accuracy for PE and PET remained moderate. These findings demonstrate that NIR spectroscopy is a viable, high throughput approach for screening MPs contamination in powdered dairy matrices, supporting its potential for routine quality control in premium food products.