Combination of Different Methods, Including Image Analysis, to Define the Fibrous Structure of High-Moisture...

Area of Science:

• Food Science and Technology
• Materials Science
• Image Analysis

Background:

• Characterizing extrudates from High Moisture Extrusion-Cooking (HMEC) is crucial for understanding their structure-property relationships.
• Existing methods like anisotropy index, spectroscopy, and microscopy offer valuable data but may not fully capture macroscale fibrous structures.
• A need exists for advanced techniques to precisely define and quantify the visible fibrous components within extrudates.

Purpose of the Study:

• To develop and validate a novel image analysis method for characterizing the macroscale fibrous structure of HMEC extrudates.
• To define and quantify the phenomenon of
• fibration
• using lamellarity and aspect of fibration tests.
• To investigate the influence of soy concentrate and wheat gluten proportions on extrudate fibration and structural properties.

Main Methods:

• Development of a new image analysis technique comprising lamellarity and aspect of fibration tests.
• Application of the method to extrudates composed of varying ratios of soy concentrate and wheat gluten.
• Integration with established techniques: anisotropy index, light microscopy, Confocal Scanning Laser Microscopy (CSLM), and X-Ray Micro-computed Tomography (XRM).

Main Results:

• Successfully defined and quantified
• fibration
• as visible fibers, potentially originating from pore walls.
• Established a criterion using the new method to identify fibered extrudates based on anisotropy index and lamellarity test outcomes.
• Demonstrated that incorporating up to 75% wheat gluten (dry basis) resulted in denser, less delaminable extrudates with reduced visible fibration compared to soy alone.

Conclusions:

• The novel image analysis method provides a robust tool for defining and quantifying fibration in HMEC extrudates.
• Wheat gluten content significantly impacts extrudate compactness, delamination resistance, and the degree of visible fibration.
• While promising, the method exhibits variability in repeatability, necessitating further refinement for broader application.