Water Effective Diffusion Coefficient in Dairy Powder Calculated by Digital Image Processing and through Machine...

Area of Science:

• Food Science and Technology
• Materials Science
• Chemical Engineering

Background:

• Rehydration of dairy powders is critical but complex to monitor.
• Existing methods for measuring powder rehydration are often labor-intensive.
• The effective diffusion coefficient is a key parameter for quantifying rehydration.

Purpose of the Study:

• To develop an automated, real-time method for measuring the water diffusion coefficient in dairy powders.
• To modify existing labor-intensive techniques using confocal microscopy and advanced imaging analysis.
• To analyze particle morphology and local hydration during the rehydration process.

Main Methods:

• Utilized confocal microscopy to capture real-time images of dairy powder rehydration.
• Developed image analysis procedures in Matlab©-R2023b for particle segmentation and labeling.
• Implemented machine learning algorithms in Python™-3.11 for data set expansion, neural network training, and particle markup.
• Applied Fick's second law for spherical geometry to model effective diffusion.
• Calculated the effective diffusion coefficient from dye intensity changes during rehydration.

Main Results:

• The developed models provide two independent, machine-based measurements of the effective diffusion coefficient.
• Effective diffusion coefficients for water showed a linear increase with increasing powder particle size.
• Results align with previously established methods for measuring powder rehydration.
• Identified morphological characteristics and local hydration of individual particles.

Conclusions:

• The automated confocal microscopy and machine learning approach offers a viable alternative to labor-intensive methods for measuring powder rehydration.
• This technique provides accurate, real-time data on the effective diffusion coefficient.
• The findings are applicable to a broad range of high-protein powders, enhancing quality control and process optimization.