Practical Applications of Food Colloids

Dickinson, E. (2004). Food colloids the practical application of protein nanoscience in extreme environments. Editorial overview. Current Opinion in Colloid and Interface Science, 9, 295-297. 

This class of association colloids can be further divided into several subgroups, which include micelles, vesicles, microemulsions, and bilayer membranes. Each subgroup of association colloids plays an important role in many aspects of colloid and surface science, both as theoretical probes that help us to understand the basic principles of molecular interactions, and in many practical applications of those principles, including biological systems, medicine, detergency, crude-oil recovery, foods, pharmaceuticals, and cosmetics. Before undertaking a discussion of the various types of association colloids, it is important to understand the energetic and structural factors that lead to their formation. 

Likewise, the practical food foreman knows that by following certain manufacturer s recommendations and certain processing conditions in his plant, he is able to produce stabilized foam products to the satisfaction of his superiors and the public, most of the time yet when problems of instability and poor shelf life of the finished product are brought to his attention and all simple adjustments fail to produce a satisfactory result, he must turn to the food or colloid chemist for the theory and industrial application of foams. 

The wide range of applications and increasing interests on the studies of nonionic surfactant reverse micelles or W/O microemulsions has shown their significance in colloid and polymer sciences. Due to biocompatibilily and biodegradability of the glycerol-based nonionic surfactants, studies on the self-assemblies of these surfactants in polar and nonpolar solvents offer various practical applications in the food, cosmetics, and pharmaceutical industries. 

Microemulsions, like micelles, are considered to be lyophilic, stable, colloidal dispersions. In some systems, the addition of a fourth component, a cosurfactant, to an oil-water-surfactant system can cause the interfacial tension to drop to near-zero values, easily on the order of 10 - 10 mN/m, allowing spontaneous or nearly spontaneous emulsification to very small drop sizes, 10 nm or smaller. The droplets can be so small that they scatter little light, and the emulsions appear to be transparent and do not break on standing or centrifuging. Unlike coarse emulsions, microemulsions are thought to be thermodynamically stable. The thermodynamic stability is frequently attributed to transient negative interfacial tensions, but this, and the question of whether microemulsions are really lyophilic or lyophobic dispersions are areas of some discussion in the literature. As a practical matter, microemulsions can be formed, have some special qualities, and can have important applications in areas such as enhanced oil recovery, soil and aquifer remediation, foods, pharmaceuticals, cosmetics, herbicides, and pesticides (13,16,45,59-61). 

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