Starch/carrageenan/milk proteins interactions studied using multiple staining and Confocal Laser Scanning Microscopy

Area of Science:

• Food Science
• Materials Science
• Colloid Science

Background:

• Understanding component interactions is crucial for food system microstructure.
• Modified waxy maize starch, kappa carrageenan, and skim milk are common food hydrocolloids and proteins.
• The microstructure of mixed hydrocolloid/protein systems influences texture and stability.

Purpose of the Study:

• To investigate the interactions between modified waxy maize starch, kappa carrageenan, and skim milk.
• To elucidate the effect of blending order on the microstructure of these ternary mixtures.
• To visualize and analyze the microstructural changes using Confocal Laser Scanning Microscopy (CLSM).

Main Methods:

• Utilized Confocal Laser Scanning Microscopy (CLSM) for microstructural analysis.
• Employed a multiple staining technique to enhance visualization of starch components.
• Prepared binary (starch/carrageenan) and ternary (starch/carrageenan/milk) mixtures with varying component addition orders.

Main Results:

• In binary mixtures, kappa carrageenan adsorbed onto and slightly penetrated starch granules.
• No direct interactions were observed between starch and milk proteins in binary or ternary systems.
• In ternary mixtures, carrageenan showed preferential interaction with milk proteins, inhibiting carrageenan-starch interactions.
• The order of component addition significantly impacted the final microstructure, influencing starch granule disruption and network formation.

Conclusions:

• Carrageenan exhibits preferential interactions with milk proteins over starch granules in mixed systems.
• The blending sequence critically determines the microstructure of starch-carrageenan-milk systems.
• Microstructural outcomes are influenced by starch-carrageenan interactions, carrageenan-protein network formation, and starch granule modification.