Rapid detection of TiO₂ (E171) in table sugar using Raman spectroscopy

Area of Science:

• Analytical Chemistry
• Food Science
• Spectroscopy

Background:

• Titanium dioxide (TiO2), widely used as a food additive (E171), has debated toxic effects.
• Accurate detection and quantification of TiO2 in food are crucial for risk assessment.
• Existing methods for TiO2 analysis in food are often time-consuming and complex.

Purpose of the Study:

• To develop a rapid, reliable method for detecting and quantifying TiO2 particles in food matrices.
• To establish a facile analytical approach for TiO2 (E171) using Raman spectroscopy.
• To address analytical gaps in the rapid assessment of TiO2 in food products.

Main Methods:

• Development of a facile Raman spectroscopy method for TiO2 detection and quantification.
• Application of sequential centrifugation and washing for TiO2 recovery from sugar solutions.
• Utilizing Raman mapping for direct TiO2 estimation in sugar granules.
• Analysis of TiO2 presence in sugar-coated doughnuts.

Main Results:

• Achieved 97% recovery of TiO2 particles from sugar solutions.
• Established a limit of detection (LOD) of 0.073 mg kg⁻¹ for TiO2 in sugar solutions.
• Demonstrated a linear relationship between Raman intensity and TiO2 concentration (5-2000 mg kg⁻¹) in sugar granules.
• Reported an LOD of 8.46 mg kg⁻¹ for TiO2 in sugar granules using Raman mapping.
• Successfully detected TiO2 in sugar-coated doughnuts.

Conclusions:

• The developed Raman spectroscopy method is rapid (<30 min) and reliable for TiO2 detection and quantification in food.
• The technique facilitates online monitoring and risk assessment of TiO2 exposure through food.
• This study provides a valuable tool for ensuring food safety concerning TiO2 additive.