The launch in the US of a frying oil containing nanoparticles underlines the potential for the use of nanotechnology in a host of food applications. Mark Rowe reports on technical innovations which could offer positive benefits to manufacturers in areas such as packaging, labelling and preserving food.
If proof were needed that nanotechnology is more than an esoteric scientific discipline then it surely comes with the news that nanotech is about to come to a fastfood restaurant near you. Last month a Californian company called OilFresh commercially launched a nanotechnology-based frying oil in the US.
OilFresh has been using nanoparticles to extend the fry life of edible oils. This is achieved by fusing nanoceramic catalytic pellets together to create a covering on the oil’s surface. These pellets are so small that oxygen cannot pass through them, which means that oxygen is diverted away from the oil allowing the oil to last longer.
Unlike conventional filtration systems, which simply filter out unwanted burned food particles or sediments in the oil, OilFresh suppresses the oil breakdown process in the first place by reducing oxydative degredation.
The company launched two brands, OilFresh 1000 and 3000, and believes “nano-oil” will appeal to fastfood chains as it will be a way to keep costs down as they move to using more expensive oils in response to consumer concerns about trans fats. The company is also targeting the Chinese and Japanese food industry. “The result is better taste, crisper deep-fried foods, better consistency of product, lower costs and greater profits,” said Sonny Oh, chief executive of OilFresh.
Other recent developments in nanotechnology look set to influence every sector of the food industry. The Institute of Nanotechnology at Stirling University, Scotland, has been among those organisations producing and collating research in the field of nano-packaging and nano-barcodes. These are molecular versions of traditional barcodes, made from metal nano-particles, which are encodeable, machine-readable and durable sub-micron-sized striped metallic rods.
According to Andy Garland, head of information at the Institute of Nanotechnology, the main benefits of nano-barcodes are in tackling counterfeit of goods. “It’s a lot harder to counterfeit goods that have nano-barcodes,” Garland told just-food. “You’re scaling things down to a level where the details are not visible to the naked eye.” A typical nano-barcode can have an extraordinary number of unique identifiers, featuring anything from 5,000 to five million particles.”
Food hygiene also stands to benefit from nano-packing and nano-barcodes. Nanoplex Technologies in California, for example, is developing barcodes that can detect pathogens in food such as E. coli. “The packaging will be able to detect if the meat – or any food – is starting to spoil,” Garland said.
In addition to giving greater durability, the incorporation of nano-materials in packaging will allow for the development of paper packaging with sensing ability and plastic bottles with gas and UV barrier properties. Nano additives can also make packaging more waterproof, or, in contrast, more absorbent. Nanoplex and others are also developing foils or membranes, based on nanocomposites that offer adjustable gas permeability in food packaging, which can help protect food better.
The oxygen-barrier technique is also being applied to foods in their own right as a way to extend shelf life. Mars is working on a patent to explore ways to develop nano-coatings for biscuits and chocolate that can allow them to last longer. The thinking is that a coating of nanoparticle silicon dioxide, which has ultra-small particles, would prevent oxygen permeating into the product, thereby reducing the need for antioxidants and preservatives.
Food tasting at the processing and new-product level also stands to benefit from nanotechnology. Gregory Sotzing, an associate professor at the University of Connecticut, is working on a project to produce an “electronic tongue”, using tiny electrodes coated with a conductive polymer that can discern flavours for taste studies on soft drinks and dairy products.
The electronic tongue, which is being developed in conjunction with Kraft Foods, will be able to detect and taste chemicals to the level of parts per trillion. And it doesn’t stop there. Sotzing is also developing another “tongue” that will operate as a detecting agent for pathogens on food, and would be able, in particular, to monitor meat for decay and raise the alert by changing colour.
A lead in this food monitoring technology has been taken by the Good Foods Project, an EU-funded research project in Barcelona, which has developed micro and nanotechnological portable devices to detect toxins, pathogens and chemicals during processing of a range of goods including dairy products, fruit juices, wine and fish. Such devices should mean that the practice of sending food samples for laboratory tests become redundant; instead the food would be analysed for quality and health standards on the spot.
“Developments in micro- and nanotechnologies present opportunities for new solutions capable of being quickly deployed where they are most needed – in the factory, supermarket or even the consumer’s home,” said a Good Foods Project spokesman. “A portable device would not only accelerate the testing procedure, but would allow more tests to be carried out on more produce samples, increasing the overall safety of the food.”