Researchers and industry must better consider the effects of multiple emulsion systems such as water-oil-water (W1/O/W2) systems when within a food matrix rather than independently, according to a new review published in Food Research International.
Led by Francisco Jiménez-Colmenero from the Institute of Science and Technology Food and Nutrition, Spain, the review highlights recent studies to investigate the potential for multiple emulsion systems as a means to modify or develop healthy and functional food products.
However, the Spanish researcher suggests that not enough of this research considers the practical applications of such emulsions in the development of functional foods.
Jiménez-Colmenero suggests that applications for such systems include improving fat content “both by reducing fat (calories) content and providing healthier fatty acid profiles”, reduction of salt and sugar levels, and the encapsulation or protection of bioactive compounds - such as minerals, carotenoids, vitamins, microorganisms, lactoferrin, phenolic compounds, amino acids and nutritional oils.
“Since multiple emulsions offer the opportunity to enclose nutritional and bioactive compounds, and these emulsions could be used as food ingredients, they offer an interesting approach among the technological strategies used to optimize dietary active components in new food systems such as functional foods,” said the Spanish researcher.
However, he noted that most research has so far focused on the design, formation, structure and properties of W1/O/W2emulsions themselves in order to achieve specific properties (such as high stability and encapsulation efficiency); without considering their potential food applications.
“As a result, it is not known how they will behave in a food matrix or hence what impact they will have on the technological, sensory and microbiological properties of complex matrixes of real foods,” he said.
“It is clear that multiple emulsions have great potential as delivery systems for functional food components, but there are still a number of important issues that need to be addressed before this technology can be successfully employed in the food industry,” said Jiménez-Colmenero.
He suggested that most of the studies related to multiple emulsions preparation are not suitable for use in food applications because they are not easily scaled up, are not cost effective or require the use of non-food grade ingredients which make such emulsions unsuitable for human consumption.
“When multiple emulsions are designed for food application – and more specifically in the development of healthier foods, as well as aspects relating to the presence of bioactive compounds – consideration must also be given to the nature and concentration of the components used in their formation, including the oil phase, the type of emulsifiers, or the inner and outer aqueous phases,”
Jiménez-Colmenero suggests, therefore, that new research aims to determine the extent to which the food-grade W1/O/W2 emulsion technology that has been developed recent years can be successfully used in food products - especially in healthier approaches and the development of functional foods.
Source: Food Research International
Volume 52, Issue 1, Pages 64–74, doi: 10.1016/j.foodres.2013.02.040
“Potential applications of multiple emulsions in the development of healthy and functional foods”
Authors: Francisco Jiménez-Colmenero