Brussels, 03 Feb 2006
A recently completed EU funded project has developed a number of novel enzymes that have the potential to improve food texture and quality, for example by making the texture of low-fat yoghurts rich and creamy.
The CROSSENZ project (novel cross-linking enzymes and their consumer acceptance for structure engineering of foods) was launched in 2002 with the aid of 1.6 million euro under the food nutrition and health key action of the Fifth Framework Programme (FP5). Having completed their research in 2005, the consortium is now investigating commercial exploitation of the technology with its industrial partners.
At a meeting in Brussels on January to present the project's results, its coordinator Professor Johanna Buchert from the VTT Technical Research Centre in Finland told CORDIS News: 'Nature is full of enzymes - our task was to take advantage of these natural tools, identify the right enzymes and produce them in sufficient quantities for production processes.'
One of Professor Buchert's VTT colleagues, Dr Kristiina Kruus, explained that enzymes are bio compounds found in all living bodies, and act as powerful and versatile catalysts that accelerate bio chemical reactions by factors of up to millions. Modifications due to enzymes occur naturally in foods - for instance in the ripening of fruit - and they have long been used industrially in bread making and cheese making. They are derived for industrial use either from microbial cultures, for example fungi and bacteria, or directly from plants, before being mass-produced under optimal conditions in bioreactors.
There are many advantages to using enzymes, continued Dr Kruus: you only need a small amount in each reaction (10 milligrams of enzyme per kilo of flour in bread making, for example), they are generally environmentally friendly and not harmful to humans, they often work best under mild reaction conditions, thus removing the need for high temperatures, and they are extremely versatile, with over 4,000 uses currently documented, though very few are commercially exploited.
Most enzymes are either used to break down molecules into smaller units with the aid of water (known as hydrolysis), to join molecules to other molecules (polymerisation), or for oxidation reactions. However, some enzymes are also able to combine biopolymers such as proteins and carbohydrates - a process known as cross-linking - creating new novel foods with new functional properties, and it is these enzymes that interested the CROSSENZ partners.
'The process went from discovery of potential enzymes to their characterisation, large-scale production and testing in potential applications,' explained Dr Kruus. 'We screened 600 microbial and plant strains, characterised their functional parameters such as pH and temperature as well as their gene structure, optimised methods for large scale production and then tested their use in bakery, meat and dairy products.' The enzymes were derived from plant and microbial sources, and produced using both conventional methods and genetic engineering techniques.
According to another project partner, Dr Jakob Nielsen from the Danish Institute of Agricultural Sciences, the goal of the project is to take normal ingredients for food products and make them better. 'Cross-linking enzymes can influence food quality in terms of gel strength, thermal stability, viscosity, volume, and water-holding capacity. [...] In future they may also be used to create more healthy products, and there is theoretical evidence that cross-linking enzymes could be used to reduce allergens in food, helping those with nut allergies or gluten intolerance, for example.'
The most well-known cross-linking enzyme currently in use is known as transglutaminase, which is added to flour to improve the volume of bread and pastry products, it is alternatively used in the restructuring of meat products. 'Novel enzymes discovered within CROSSENZ will be able to be applied in similar areas,' believes Dr Nielsen, as well as in dairy products such as ice-creams, yoghurts and cheese, fruit products such as jams, fat-based products such as margarine and chocolate, and certain fine foods.
While the partners are confident that the novel enzymes they have discovered within the project can offer real benefits to manufacturers and consumers, the public's reaction to genetically modified (GM) food in recent years has shown that gaining consumer acceptance for new food technologies can be a tricky business. That's why a major part of the CROSSENZ project focused on assessing consumer attitudes to the use of enzymes in food, and their production using either conventional or GM technology.
According to Klaus Grunert, from the 'Centre for research on customer relations in the food sector' (MAPP) in Aarhus, Denmark, who led the consumer study, asking people whether they like enzymes is not very useful, as very few know anything about them. 'First you have to give the public some general information about enzymes,' he said.
Professor Grunert and his colleagues carried out surveys of 400 consumers in three different countries - Germany, Finland and Italy. They sought to assess their attitudes towards the four different methods of enzyme production used in the project (non-GM plant, GM plant, non-GM microbe and GM microbe). 'Most positive were non-GM methods, and plant derived enzymes are more popular than microbe derived ones,' revealed Professor Grunert. 'Consumers obviously feel that some forms of production are more natural or 'better' than others.'
People's attitudes to enzymes in general appeared to be quite neutral, according to the studies, but as soon as they hear about GM technologies in relation to food production they switch off, said the Professor. 'This provides an insight into how people form opinions about things they know very little about. There is evidence that when people have to form an opinion about something specific like gene technology as a tool in enzyme production, they try to relate it to wider beliefs about, e.g., tampering with nature, openness to technological progress, or environmental protection. So their wider socio-political beliefs 'colour' their views about enzymes.'
What Professor Grunert then set out to discover was whether giving people more information would help to change their opinions. Those involved in the survey were given a fake 'press release' from an authoritative consumer panel giving more information about enzymes produced with GM technologies and concluding that they should be used in food production. 'We found that this had absolutely no effect,' said Professor Grunert. 'Consumer attitudes to GM technology are resistant to information and persuasion because they are linked to underlying socio-political beliefs.'
At this point, Professor Grunert says he could have stopped and told the other partners to concentrate their efforts on enzymes derived without using GM technology. However, he wanted to discover whether direct experience would have more of an impact on people's attitudes than information alone. Therefore, his team conducted another study where consumers could actually compare the products - a normal product and one enhanced to give the improved quality expected with the addition of the cross-linking enzymes (the actual enzymes could not be given to consumers as they haven't yet been approved).
The results were surprising. In Italy, over 90 per cent of those surveyed said they preferred the 'enzyme enhanced' product, even when told that it made use of GM technology, while in Germany and Finland nearly 60 per cent said they preferred the enzyme treated option. The implications of these results are twofold, according to Professor Grunert: 'Firstly, that direct sensory experience with a real product leads to different attitude formation than exposure to information, and secondly, that it is possible that consumer attitudes to GM can be turned around by putting them on the market and letting them try them.'
It may appear an unnecessary risk to use genetic engineering techniques to produce the enzymes when consumers are obviously more willing to accept conventional approaches, but Professor Buchert told CORDIS News that it is easier and more economically viable to use genetic engineering techniques to produce industrial quantities of the enzymes.
To date, the CROSSENZ project has resulted in the discovery of many novel enzymes with cross-linking potential, a greater mechanical understanding of enzyme models, the validation of novel production concepts, and an improved understanding of consumer attitudes towards enzymes.
So far, the consortium has filed one patent, but other applications are being developed further with the industrial partners in the project. 'It still takes years to go from research to consumer products, and it will be at least two or three years before any applications are ready to be launched,' Professor Buchert told CORDIS News. 'But there is lots of potential in this area, and [the CROSSENZ partners] are looking for further opportunities in EU funded programmes. I see a very bright future for this technology.'
The European Commission Project Officer for CROSSENZ, Rosanna D'Amario, concluded: 'The value of this project is that it has incorporated consumer science as well as food technology. We often talk about consumers, but this project really made an effort to see what consumers think about these enzymes.'
CORDIS RTD-NEWS/© European Communities, 2005
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