Microstructural studies of imitation cheese with a shift in continuous phase

Area of Science:

• Food Science
• Materials Science
• Microscopy

Background:

• Imitation cheese functionality is linked to its microstructure, influenced by casein and starch components.
• Understanding microstructural changes is crucial for optimizing imitation cheese properties.

Purpose of the Study:

• To investigate microstructural differences in imitation cheese when casein is replaced by starch.
• To analyze the impact of starch modification and protein prehydration on imitation cheese microstructure and macrostructure.

Main Methods:

• Utilized Confocal Laser Scanning Microscopy (CLSM) for component identification.
• Employed Scanning Electron Microscopy (SEM) and Cryogenic Scanning Electron Microscopy (Cryo-SEM) to study surface structures.
• Assessed macrostructural properties like hardness.

Main Results:

• SEM and Cryo-SEM revealed distinct surface structures, with SEM showing rough starch and smooth protein, while Cryo-SEM did not detect starch roughness.
• Octenyl succinic anhydride (OSA) modified starch led to fragmented protein microstructure at 7% protein concentration.
• Emulsifying starch increased imitation cheese hardness, particularly at 7% and 9% protein levels; protein prehydration had minimal effects.

Conclusions:

• Microscopy techniques effectively differentiate microstructural components and surface characteristics in imitation cheese.
• Emulsifying starch significantly alters imitation cheese microstructure and increases hardness, with effects dependent on protein concentration.
• Protein prehydration shows limited impact on the microstructure and hardness of imitation cheese with 50/50 casein-starch composition.