Nanostructuring could be key to reducing saturated fats

New 'nanostructuring' techniques that turn liquid oils into more functional solid fats could replace controversial methods including partial hydrogenation or inter-esterification (using acids or enzymes to harden oils), say US scientists.

They could also prove to be a key weapon in the fight to reduce saturated fat in bakery products, according to George John, associate professor at the City College of the City University of New York.

While the monounsaturated fatty acids in liquid oils such as olive or rapeseed oil are better for you, bakers in particular need to use harder fats, which contain more unhealthy saturated fats, said John, who was speaking at a Leatherhead Food Research conference on nanotechnology last month.

New technology able to create unsaturated semi-solid fats from liquid oils is therefore attracting interest from the food industry, said John, who specialises in developing nanomaterials that are self-assembled from the 'bottom up' (rather than using 'top-down' techniques that make larger particles smaller).

"Current methods [for hardening liquid oils] such as partial hydrogenation, inter-esterification or adding fatty acids can be problematic, so we're looking to generate sugar-based short chain molecular gels as new oil gelators [substances that could be added to liquid oils which makes them go semi-solid]. These could be used in confectionery and baking."

He added: "We have developed a few sugar-based amphiphiles, which showed excellent oil-thickening ability, but this work is still in the developmental stage and we do not think that there are any such molecules currently on the market."

Oil gelators had been used industrially in the past to make some frying oils spoonable, said fats and oils expert Geoff Talbot, but this was new.

"Unilever had a product called Superfry using this technology, but not using sugar-based substances to achieve it," said Talbot.

Unilever also spoke at the conference. The consumer goods giant highlighted a series of novel techniques for creating nano emulsions enabling the more efficient delivery of nutrients including high pressure homogenisation, microchannel emulsification and a new 'melt' emulsification process.