Quality control of deodorant by nearinfrared spectroscopy

Significance of the topic

Quality inspection of deodorant formulations is essential to meet regulatory and consumer expectations. Rapid assessment of parameters such as pH, density, viscosity and aluminum content can enhance production efficiency and ensure product safety.

Objectives and study overview

This application note explores the use of near-infrared spectroscopy for fast, reagent-free analysis of deodorant quality attributes. The goal was to develop robust prediction models for pH, density, viscosity and aluminum content using spectral data acquired in seconds.

Methodology and instrumentation

Sixty deodorant samples were measured in transflection mode over the 1000–2250 nm range on an OMNIS NIR Analyzer Solid with a 1 mm large reflector and a 60 mm transflection vessel. Reference methods included titration for aluminum, a pH meter, viscometry and density measurement. OMNIS Software handled data acquisition and model calibration.

Main results and discussion

Prediction models demonstrated strong agreement with reference data, yielding R2 values of 0.908 for aluminum content, 0.979 for density, 0.941 for viscosity and 0.832 for pH. Figures of merit such as SEC, SECV and SEP confirmed the precision required for routine quality control. The high spectral sensitivity allowed accurate quantification without any sample preparation.

Benefits and practical applications

• Analysis completed in seconds without chemical reagents
• At-line integration supports real-time monitoring during production
• Reduces laboratory workload, costs and turnaround time

Future trends and possibilities

Advancements in portable NIR instruments and machine-learning algorithms will further improve predictive accuracy and expand applicability to complex personal care matrices. Automated sampling and digital integration are expected to streamline end-to-end production quality workflows.

Conclusion

Near-infrared spectroscopy offers a rapid, non-destructive means to quantify key deodorant quality parameters. This approach enables efficient, cost-effective quality assurance both at-line and offline, contributing to streamlined manufacturing processes.

Used instrumentation

• OMNIS NIR Analyzer Solid
• Large reflector OMNIS NIR, 1 mm
• Transflection vessel OMNIS NIR, 60 mm
• OMNIS Software Quant Development and Stand-Alone licenses