LONDON In a taste of things to come, food scientists say they have cooked up a way of using nanotechnology to make low-fat or fat-free foods just as appetizing and satisfying as their full-fat fellows.
The implications could be significant in combating the spread of health problems such as obesity, diabetes and heart disease.
However, experts say nanotechnology's future in food could be thwarted before it gets started by a reluctance among food manufacturers fearful of the kind of European consumer backlash that greeted genetically modified (GM) food to be open about what they are doing.
They say this refusal to communicate could foster the same mistrust that led GM to be branded "Frankenstein food" in many parts of Europe and could mean some of nano food's potential remains unfulfilled for years.
"What the food industry is doing in research labs is looking at new possibilities of creating new products, and they're using the toolbox of nanotechnology to do that," said Frans Kampers, who coordinates research on food nanotechnology at Wageningen University and Research Center in the Netherlands.
"But I think the industry should be more open. It should show what ... could come onto the market within the next two or three years, because if we don't prepare society for these products ... we may be throwing away all these opportunities."
Nanotechnology is the science of manipulating matter at the nano scale -- one thousand millionth of a meter -- which, among other things, may be used to alter when, how and where in our bodies food is digested.
According a British parliamentary report, the global market for nanotechnology in food was $140 million in 2006 and is expected to balloon to $5.6 billion in 2012.
Like Kampers, British lawmakers expressed concern that not enough research is being done into potential nano food risks, and frustration about the food sector's lack of communication.
Reuters contacted Unilever, Kraft and Nestle, three of the world's biggest food firms, but only one wanted to talk at length about nanotechnology.
Nestle said in an emailed statement it "does not do research in the field of nanotechnology." Kraft said it did not use nanotechnology now, but its research and development teams "always keep their eyes on the scientific research."
A Unilever research director, Charles-Francois Gaudefroy, was more forthcoming, saying that while the firm did not use nanotechnology in any of its foods at the moment, it was looking seriously at potential applications for the future.
"We need to go further into understanding how matter works, and then bring that knowledge into how we prepare food for our products," he told Reuters. "We're at the very beginning."
One thing they might look into is work by scientists at Britain's Institute of Food Research (IFR), who said last month they had found an unexpected synergy that helped break down fat and might lead to new ways of slowing digestion, and ultimately to creating foods that made consumers feel fuller.
"Much of the fat in processed foods is eaten in the form of emulsions such as soups, yoghurt, ice cream and mayonnaise," said the IFR's Peter Wilde. "We are unpicking the mechanisms of digestion used to break them down so we can design fats in a rational way that are digested more slowly."
The idea is that if digestion is slower, the final section of the intestine called the ileum will be put on its "ileal brake," sending a signal to the consumer that means they feel full even though they have eaten less fat.
Experts see promise in another nano technique which involves encapsulating nutrients in bubble-like structures known as vesicles that can be engineered to break down and release their contents at specific stages in the digestive system.
According to Vic Morris, a nano expert at the IFR, this technique in a larger form, micro-encapsulation, was well established in the food industry. The major difference with nano-encapsulation was that the smaller size might be able to take nutrients further or deliver them to more appropriate places.
Morris and Kampers appeared relatively unperturbed about the potential risks of nanotechnology when used in these ways, but when it came to nanoparticles, their concern grew.
Nano particles measure between one and about 100 nanometres with a high surface-to-volume ratio, which essentially allows them to be more active than their larger cousins.
Saltier tasting salt, or iron that could be better absorbed by the body to tackle iron-deficiency anemia are two forms of nanoparticles touted as possibilities for improving food.
In an effort to find a way of being able to label or regulate the use of nanoparticles in future, the European Commission has set up a research project called NanoLyse aimed at devising ways of detecting and measuring nano technology in foods.
The project's website says that, as yet, "very limited knowledge is available on the potential impact of engineered nanoparticles on consumers' health."
Concerned experts cite some research that has found that "persistent" nanoparticles that do not dissolve or biodegrade, such as nanosilver which can be used in food packaging as a way of extending shelf life, may penetrate certain barriers within the body that mean they pose a danger.
"These particles could be hazardous and we need to know more about their effects both in the body and in the environment," said Kampers. "Since these particles are very small, they can...enter cells or even the nucleus of a cell if they have the right characteristics."
(Editing by Andrew Dobbie)