Nanoscience could help manufacturers develop products with a lower glycaemic index (GI) by enabling them to scrutinise starches at a sub-molecular level, according to the Institute of Food Research.
Speaking at the Nutracon Europe conference, IFR scientist professor Vic Morris said that powerful atomic force microscopes (AFMs) that created images by ‘feeling’ the surface of samples using sharp probes were helping researchers see precisely how starch granules behaved as they were heated up.
GI is increased when starch granules gelatinise or swell through heat, enzymatic processes or pressure.
By watching what happened to different cereals samples using the AFMs, they could identify ‘mutant’ samples with higher levels of resistant starch (and therefore a lower GI) and use this information to develop new strains, either through traditional plant breeding or genetic modification, said Morris. “Nanoscience provides the information to enable the selection of novel starches. By understanding starch at a nano-level, you can rationally modify its resistance.”
The microscopes were also helping manufacturers to develop better foams and emulsions by enabling them to “see the types of structures formed, and the changes that occur as molecules compete to control and colonise interfaces”, he said.
“The AFM can sense the contours of a surface and generate a three-dimensional image. By creating model air-water or oil-water interfaces, and populating them with various molecules, we can see the structures formed and understand the nature of the interactions between the molecules.”
Companies pioneering the use of nano-encapsulation to produce clear liquids containing water and fat-soluble bioactive ingredients were also working with food manufacturers looking to boost the bioavailability of ingredients like vitamin E, omega-3s or soy isoflavones in functional drinks, he said
So called ‘nano-encapsulation’ technology is based on nano-sized carriers that mimic the body's natural delivery systems for nutrients and therefore increase their bioavailability.