There is good news for snack-lovers: Crisps could be about to get healthier.
Crisps contain acrylamide, which is a chemical substance formed when starchy foods, such as potatoes and bread, are cooked at high temperatures.
There is evidence from studies in animals that the chemical is linked to cancer, making people more concerned about their roast potatoes and burnt toast, although experts are divided on whether the substance could cause the disease in humans.
But now researchers may now have worked out how to reduce the amount of acrylamide formed when deep-frying potatoes to make crisps.
The key is to use the right kind of potato, which has achieved the right level of maturity before being harvested.
Less mature potatoes contain more sugar, which can be converted into acrylamide, according to the Norwegian research institute SINTEF.
Crisps contain acrylamide, which is a chemical substance formed when starchy foods, such as potatoes and bread, are cooked at high temperatures
It follows similar work in the UK, where scientists at Rothamsted Research have gone further in using gene editing to develop a type of wheat which is less likely to produce acrylamide when it is toasted within bread.
When it comes to crisps, the Norwegian researchers found measuring the level of sucrose and aspartic acid in potatoes provided the best indicator of the amount of acrylamide they would produce when being deep-fried to make crisps.
But Dr Erlend Indergård, from SINTEF, said: ‘This method is slow and requires the use of expensive instruments.
Acrylamide: All you need to know
Acrylamide is considered so toxic that in drinking water, only 0.1 micrograms per liter is allowed, 100 times less than the amount of arsenic allowed.
This is to protect consumers against acrylamides used in industry (where it is used to make dyes and plastics).
The chemical is not intentionally added to food.
Instead, it is produced when carb-laden foods that naturally contain an amino acid called asparagine are heated to above 120c, such as from baking, BBQing, frying, grilling, toasting or roasting.
Crisps and chips have been found to contain high levels of acrylamide; pizza, toast and biscuits are also on the danger list.
The World Health Organization has said the levels of acrylamide in food pose a ‘major concern’.
But unlike water, there is no legal maximum.
Acrylamide is not yet proven to be a carcinogen in humans, despite some studies suggesting it does in animals.
‘We’ve found that measuring glucose concentrations using a blood sugar meter that anyone can purchase at a local pharmacy offers a quicker and more accessible means of getting an indication of whether a potato’s sugar content is too high.’
Potatoes also need to be stored at the right temperature, according to experts.
The Food Standards Agency (FSA) recommends that people reduce their consumption of acrylamide when preparing food at home by aiming for a golden yellow color or lighter color when frying, baking, toasting or roasting starchy foods.
They also suggest following the instructions on the pack when cooking packaged foods such as chips and roast potatoes.
Mark Willis, head of chemical contaminants at the Food Standards Agency, said: ‘We welcome the development and use of good practice by businesses to manage acrylamide, including sourcing of ingredients and appropriate storage.’
Dr Claire Knight, senior health information manager for Cancer Research UK, said: ‘There is no good evidence that eating foods high in acrylamide, such as crisps, toast, or charred root vegetables, will increase your risk of cancer.
‘Some foods with acrylamide are high in calories though, and being overweight or obese increases the risk of 13 types of cancer.
‘Your overall diet is more important than individual foods to reduce cancer risk.’
Dr Duane Mellor, registered dietitian and senior lecturer at Aston University, said: ‘Although it is good to reduce acrylamide levels in crisps, as it is a known carcinogen, removing it will not make crisps healthy as they will still be high in fat and probably salt, and low in fiber and vitamins.’
In 2017, research by the Changing Markets Foundation, which reviewed 92 potato snacks from major UK brands as well as own-brand supermarket crisps, reported high levels of acrylamide in 17 per cent of those sampled.
Nusa Urbancic, director of campaigns at the Changing Markets Foundation, which supports sustainable products, said: ‘While we welcome such innovation in reducing acrylamide levels, it is important to emphasize that the food industry has been well aware of this problem and also of the solutions for more than two decades.’