Characterizing a model food gel containing bubbles and solid inclusions using ultrasound

Area of Science:

• Food Science
• Materials Science
• Acoustics

Background:

• Characterizing heterogeneous materials with multiple inclusion types is challenging.
• Distinguishing between bubbles and solid particles in food structures can be difficult using traditional imaging.
• Maintaining food quality requires precise control over ingredient incorporation and structural integrity.

Purpose of the Study:

• To apply ultrasonic spectroscopy for characterizing a model aerated food system.
• To differentiate and measure the sizes of embedded bubbles and solid beads.
• To assess the potential of ultrasonic spectroscopy for quality control in functional foods.

Main Methods:

• Utilized ultrasonic spectroscopy to analyze an agar gel model system.
• Embedded both air bubbles and polystyrene beads within the gel matrix.
• Exploited distinct acoustic resonance frequencies of bubbles and beads for characterization.

Main Results:

• Successfully measured the sizes of bubbles and beads using ultrasound.
• Demonstrated accurate size measurement even when inclusions were optically indistinguishable.
• Showcased the frequency-dependent nature of acoustic resonances for differentiation.

Conclusions:

• Ultrasonic spectroscopy is effective for characterizing soft heterogeneous materials with mixed inclusions.
• The technique is highly relevant for functional foods requiring precise structural evaluation.
• Enables quality assessment of aerated foods with incorporated solid ingredients without structural degradation.