Food to die for?

An ingredient associated with cancer is every food manufacturer's nightmare and, while UK consumers are currently oblivious to the danger, the industry isn't taking any chances.

"Acrylamide is not something that manufacturers can ignore," says Snack, Nut and Crisp Manufacturers Association (SNACMA) scientific regulatory affairs manager Dr Robert Foot. Any responsible processor recognises that work needs to be done to reduce acrylamide levels, he says.

It is created when asparagine and 'reducing sugars' (ingredients which occur naturally in potatoes, wheat and rye) react during baking and frying. When acrylamide was first discovered, manufacturers were responsible for 50% of its production, while the rest was produced through catering and home cooking.

Industry has made considerable strides in recent years and manufacturers have now cut their acrylamide contribution to 30%, using various techniques to lower precursor levels, and in doing so, reducing acrylamide.

Crisp manufacturers in SNACMA choose potatoes with low levels of reducing sugars grown especially for potato crisps, says Foot. Another tactic they use is to avoid storing potatoes below 6 °C as this encourages the accumulation of reducing sugars, he claims.

Snack manufacturers also recognise the relationship between acrylamide levels and the colour of crisps. "The secret is to find a light golden crisp -- it's the holy grail," says Foot.

Since acrylamide's discovery, four reports published have failed to make a direct link between it and increased incidence of cancer in humans. But Foot believes the jury is still out. "If we thought acrylamide wasn't an issue, we wouldn't continue the way we are -- it's better to be prepared," he adds.

Snack manufacturer Jonathan Crisp is equally wary that the next food scare could be just around the corner. "At the moment the media is focusing on school meals, but acrylamide could be the next scandal," says technical manager Peter Oughton. If consumer awareness about acrylamide grows, Jonathan Crisp plans to make a reduced acrylamide declaration on its packaging, but at the moment, says Oughton, people wouldn't understand it.

For the past two years, the company has endeavoured to lower acrylamide levels. It has reduced its oil frying temperatures to 140°C as heating below 200°C significantly lowers acrylamide levels, says Oughton. "Lower temperatures mean longer cook times, which slows down the plant, but acrylamide reduction takes precedence over production speed." The company also uses high quality sunflower oil because hydrogenated oils have been linked to acrylamide, he says.

However, there are limits to what food manufacturers can do to reduce acrylamide levels. "There's little room for manoeuvre in production processes -- it's incremental rather than dramatic," says Central Science Laboratories principle scientist Laurence Castle. It is impossible to remove acrylamide completely if you fry a potato, he says. "By instinct you do the easy steps first. It's the law of diminishing return -- it progressively becomes more and more difficult."

Castle explains that acrylamide is closely linked with the way food browns, and it is difficult to disentangle it from flavours and textures. "Yes, it's possible to remove acrylamide, but food wouldn't sell," he remarks. "We know what the precursors are, but these follow the formation of tasty food. Any reduction is very hard."

The problem is that cooking naturally produces acrylamide. "Acrylamide has been in our food since man had fire ... but now we can measure it," says Castle.

Castle describes the proposed Codex Alimentarius code of practice (see above) as "a half way house" in an attempt by the authorities to be seen to be doing something in the absence of any legal limits on acrylamide levels.

But without legislation or pressure from retailers or consumers, some smaller manufacturers have little incentive to reduce acrylamide levels in their products -- especially when other business issues are more pressing.

"Currently we aren't doing anything to reduce levels," admits Owain Ap Gruffydd, technical manager, at crisp manufacturer Tyrrells. "We've got a British Retail Consortium audit coming up and our key focus is to pass that." Tyrells does, however, plan to reduce acrylamide in the near future.

For many small companies, action will be retailer driven. "There won't be any pressure until the big four [Asda, Tesco, Sainsbury and Morrison] push for a reduction," says Ap Gruffydd.

It is understandable that small companies are slower to react than large ones, says Leatherhead Food International senior research scientist Rachel Burch. "Many manufacturers want to know more before they act," she says.

Smaller manufacturers also don't have the financial resources to make process changes that may be required. So they are more likely to wait for legislation before taking action to reduce acrylamide, she adds.

The challenge remains in finding ways of dealing with the problem at source. "Acrylamide levels would be reduced if there was a way to lower the precursor," says Burch. "But in many cases, the ingredient is intrinsically in the food."

Levels of acrylamide need to be reduced without altering other nutrient properties, she adds. "Some mitigation techniques have looked at adding different compounds such as sodium, but then the product's salt levels will be high." Burch adds that some flours have lower acrylamide levels than others, but they may not be acceptable for use in all products.

Burch had planned to carry out a project looking at the problem of acrylamide, but lack of support from manufacturers meant the plans had to be shelved. Rather than putting this down to apathy, Burch generously attributes it to companies' probable involvement in other acrylamide projects.

Another research project into the issue sponsored by the Food Standards Agency and the Rothamstead agricultural research centre involves Reading University under the leadership of senior research fellow Dr Stephen Elmore. This project is looking at genetically modified (GM) potatoes with reduced levels of acrylamide precursors.

While consumers may have reservations about the use of a GM product, says Elmore, the benefits may outweigh any concerns they have. Reading is also carrying out an agronomical study looking at the minerals in the surrounding soil to see if they affect the precursors formed in potatoes.

Thus, the solution to the problem of acrylamide may ultimately lie in dealing with the issue at source.

"You can only go so far with acrylamide reduction in processing," says Elmore. "Altering cooking times may change the texture of a product and flavour. I don't see what else processors can do." FM

the story so far:

In April 2002 Swedish scientists discovered that acrylamide, a chemical compound known to cause cancer in rats, formed organically during the browning process of cooking.

Levels of acrylamide are high in fried foods such as crisps, chips and crackers.

Industry, government and research associations worldwide have endeavoured to find out more about acrylamide.

The Joint Expert Committee on Food Additives, a body set up by the World Health Organisation in collaboration with the United Nations' Food and Agricultural Organisation to carry out risk assessments, claims that acrylamide may be harmful to human health. However, it will reassess the likely health implications of acrylamide when more toxicological studies become available.

In the meantime, the Food Standards Agency has advised food manufacturers to reduce acrylamide levels as far as possible. And the global food standards body Codex Alimentarius is working on a code of practice for the reduction of acrylamide in food.