Non-contact diffuse reflectance spectroscopy using center-illuminated-area-detection modeled by a simple formula for...

Area of Science:

• Optics and Spectroscopy
• Biophysics
• Food Science

Background:

• Diffuse Reflectance Spectroscopy (DRS) is crucial for non-contact analysis of chromophores like myoglobin in meat.
• Accurate spectral absorption recovery is challenging in non-contact DRS due to complex light scattering.
• Assessing myoglobin forms is vital for understanding meat discoloration.

Purpose of the Study:

• To develop and validate a simple forward model for non-contact DRS in a center-illuminated-area-detection (CIAD) geometry.
• To demonstrate the model's effectiveness in recovering spectral absorption for chromophore decomposition.
• To apply the model to assess myoglobin changes in meat during retail display.

Main Methods:

• Utilized Monte Carlo simulations to examine a simple DRS forward model in CIAD geometry across varying absorption and scattering coefficients.
• Compared the performance of the simple model against a previous, more complex model for the same geometry.
• Applied the validated simple model to non-contact DRS measurements of beef steaks over a 6-day retail display period.

Main Results:

• The simple forward model for DRS in CIAD geometry significantly outperforms previous models, especially at high absorption levels.
• The model accurately recovers spectral absorption, enabling direct chromophore proportion analysis with prior scattering knowledge.
• Non-contact DRS measurements using the simple model showed myoglobin changes consistent with contact DRS assessments.

Conclusions:

• A simplified forward model for non-contact DRS in CIAD geometry offers a convenient method for spectral absorption recovery.
• This approach facilitates the decomposition of spectrally significant chromophores, such as myoglobin forms.
• The validated model provides reliable insights into meat discoloration by tracking myoglobin changes over time.