The combination of protein and polysaccharides used by the group create the same texture and feel as oil-containing emulsions - without the need for an oil phase.
Led by Hans Tromp of NIZO food research, the SOMATAI (Soft Matter At Aqueous Interfaces) project findings pave the way for the food industry to create low-fat or fat-free products with a creamy mouth feel, said NIZO.
The team behind the development noted that emulsions of water-soluble ingredients offer the possibility to simulate the experience of fat with low-caloric substitutes. Indeed, the development of 'water-water' emulsions using food grade polymers to replicate the feeling of fat in an emulsion.
“An emulsion consisting of gelatin and a polysaccharide whose gelatin-rich emulsion droplets have been gelled to make them stable could be used to replace a portion or all of the fat or oil globules in emulsions such as mayonnaise, cream or dressings,” explained Tromp.
Fat-free emulsions
NIZO noted that the creation of a water-water emulsion that can successfu replicate the mouthfeel of an oil-water emulsion can be difficult because the surface tension at the interface is many times smaller than that in oil-water emulsions.
Because this surface tension is the factor responsible for instability, and gives the creamy mouth feel of emulsions, it is important that a water-water emulsion must also 'destabilise' in a similar way.
This destabilisation forms a film of oil or fat covering part of the surface of the tongue - so creating the perception of creaminess.
The project has identified several food-grade water-water emulsions that are able to stabilise a food matrix whilst also offering enough 'destabilisation' to offer a creamy mouth feel, said Tromp.
“The next step is to test this in foods," he added. "There is more that we intend to investigate, for example the use of such an emulsion as a template for the growth of microbes or as a platform for controlled release. This makes it a very promising technique.”