Glass transition temperature and its relevance in food processing

Area of Science:

• Food science and technology
• Materials science
• Physical chemistry

Background:

• Amorphous, noncrystalline solids are common in low-water and frozen foods, forming nonequilibrium glass-like structures.
• These glassy states arise from reversible glass transitions during food processing.
• Vitrification and various relaxations occur around the glass transition in these states.

Purpose of the Study:

• To highlight the importance of the glassy state in food processing and stability.
• To explain the role of glass transition in dehydrated and frozen foods.
• To emphasize the impact of water plasticization on food deterioration.

Main Methods:

• The abstract discusses concepts related to food processing, dehydration, and storage.
• It references the phenomenon of glass transition and vitrification in amorphous solids.
• Key factors like water activity and water content are mentioned in relation to plasticization.

Main Results:

• Success in freeze drying, spray drying, extrusion, and food stability relies on controlling the glassy state.
• Glass-forming materials are vital for encapsulation and retention of volatiles.
• Water and temperature plasticization accelerate deterioration by reducing relaxation times.

Conclusions:

• Controlling the glassy state during dehydration and storage is essential for successful food processing and stability.
• Understanding water plasticization and its effect on glass transition is critical for preventing food deterioration.
• Critical water activity and content values indicate the level of plasticization impacting food storage.