Raman Spectroscopy Coupled with Chemometric Techniques for Authenticity Assessment of Camel Milk Powder.

Background: Adulteration of camel milk powder with cheaper alternatives such as cow milk powder has become a growing concern, compromising both nutritional quality and consumer trust. Detecting such adulteration is critical for ensuring product authenticity, especially given the rising demand for camel milk in niche health markets.

Objective: This study explores the application of Raman spectroscopy in conjunction with chemometric techniques for the detection and quantification of adulteration in camel milk powder with cow milk powder.

Method: Camel milk powder was adulterated with cow milk powder across a range of concentrations from 0% to 50%. Raman spectra of these mixtures were analyzed using PCA for dimensionality reduction, followed by PLSR modeling with different spectral pretreatments (raw, Savitzky-Golay, gap derivative). Interval PLS (IPLS) in backward mode was applied to enhance variable selection.

Results: PCA captured 99.6% of spectral variance. The raw PLSR model already showed strong predictive power (R2cv = 95.93%). Savitzky-Golay further boosted performance (R2test = 99.47%), while the gap derivative achieved near-perfect prediction (R2test = 99.94%, RMSEtest = 1.10). IPLS modeling significantly improved robustness, yielding high accuracy (R2test = 98%) with fewer variables.

Conclusion: The findings indicate that the integration of Raman spectroscopy with PCA, PLSR, and IPLS constitutes a robust, precise, and reliable approach for the detection of adulteration in camel milk powder.

Highlights: The application of Raman spectroscopy coupled with chemometric modeling proves to be an efficient and robust analytical tool for quality control in the dairy industry, enabling the accurate detection of adulteration and ensuring the authenticity and safety of camel milk powder.