Functionality and Structure of Hydrocolloids in Dairy Foods

Abstract Text: Stabilizing gums, e.g., guar or cellulose gum or modified starches, have been used in dairy products such as yogurts and ice cream mix for many years, for thickening and enhanced eating pleasure and for enhanced stability and shelf-life. Some unique gums rely on specific milk protein interactions, e.g., carrageenan in chocolate milk or pectin in acidified milk beverages.  Many of the polysaccharide stabilizers are incompatible with milk proteins, particularly casein micelles, and carrageenan plays a unique role at inhibiting phase separation. While this body of knowledge regarding “traditional” usage of hydrocolloids is well established, there has been much research to expand the understanding and scope of hydrocolloid utilization in dairy products. Novel dairy products have been introduced into the markets, an example could be squeezable-tube products, and these products create unique demands for physical functionality, which leads to creative product development in the application of hydrocolloids. Novel hydrocolloids, particularly from agricultural by-products such as flaxseed gum or soy soluble polysaccharide, are continually being examined for potential applications. Hydrocolloids have been shown to form complexes with both casein and whey proteins under certain conditions of processing, and these complexes offer potential for new structures in dairy products. Hydrocolloid addition is also being viewed for health benefits, as most are soluble dietary fibres. Hydrocolloids in dairy products offering enhanced glycemic index reduction is an area of exciting research and product development potential, particularly in the light of rapidly rising Type II diabetes rates in the population. Hydrocolloids such as sodium alginate can also help to confer post-prandial satiety, which may present another opportunity for dairy product positioning in in the context of rising rates of obesity in the population. Given this growing demand for more functional and nutritional foods, it is critical that opportunities from within the hydrocolloids sector continue to be exploited in dairy products.

Keywords: stabilizers, functionality, dietary fibre