The big coffee CON: 1 in 10 premium products labelled ‘100% Arabica’ contain inferior and cheaper Robusta beans
- The Quadram Institute in Norwich discovered a new detection method
- It takes 30 minutes and is sensitive enough to detect just one per cent Robusta
- A total of 60 different coffee samples were tested from around the world
- Two of the ‘suspicious’ samples, bought in the UK, contained 21.7% Robusta
- Suspicious samples were also obtained from the US, Italy, France and Estonia
Coffee lovers are being conned by suppliers fraudulently mixing inferior beans into products labelled ‘100 per cent Arabica’, scientists have learned.
The discovery came to light as a result of researchers trying out a new and more accurate method of testing coffee quality.
As part of the study, members of the team and collaborators around the world bought samples of coffee on sale at shops and in supermarkets.
They found that a tenth of high quality products labelled ‘100 per cent Arabica’ contained significant levels of inferior and cheaper Robusta beans.
Among those tested from the UK high street, one Mexican coffee claiming to be 100 per cent Arabica was one-fifth Robusta.
Suspicious samples were also obtained from the US, Italy, France and Estonia. One US sample was a third Robusta, despite being labelled ‘100% Arabica’.
In the UK, a kilo of Italian Lavazza ‘100% Arabica’ beans sells for £15, while in the US it costs $25.
A spokesman for the institute behind the research said it was not possible to name the brands involved.
Scroll down for video
Coffee lovers are being conned by suppliers fraudulently mixing inferior beans into products labelled 100 per cent Arabica, scientists have learned. The discovery came to light as a result of British researchers trying out a new and more accurate method of testing coffee quality
Arabica coffee trades at twice the price of Robusta because of its superior taste.
Adulteration with Robusta coffee, which is higher yielding and easier to grow, has always been a potential problem.
But finding rogue Robusta in a sample labelled Arabica is not easy, especially after grinding and roasting.
The standard technique detects the fingerprint chemical 16-OMC, which is only found in Robusta coffee, but is costly and takes three days.
This makes large scale surveillance impractical.
Experts from the Quadram Institute in Norwich, formerly known as the Institute of Food Research, found a new method that takes only 30 minutes and is sensitive enough to detect just one per cent Robusta in a blended coffee.
Lead scientist Dr Kate Kemsley said: ‘This is an important milestone for detecting fraud in coffee, as one per cent is the generally accepted cut-off between trace contamination, which might be accidental, and more deliberate adulteration for economic gain.’
For the study a total of 60 different coffee samples were purchased in consumer countries around the world, including 22 from the UK.
As part of the study, members of the team and collaborators around the world bought samples of coffee on sale at shops and supermarkets. They found that a tenth of high quality products labelled ‘100% Arabica’ (pictured) contained significant levels and cheaper Robusta beans
WHAT IS THE DIFFERENCE BETWEEN ARABICA AND ROBUSTA COFFEE BEANS?
Although Arabica and Robusta coffee may appear similar appearance – there are a number of differences that significantly differentiate these two popular species of coffee.
The Arabica coffee shrub typically grows between 8.2 to 14.7 ft (2.5 to 4.5 metres) in height, and requires a temperature between 15 to 24°C (59 to 75°F) and an annual rainfall of between 47 and 86 inches (1,200 and 2,200 mm) per year.
Robusta grows slightly taller at 8.2 to 21.3 ft (4.5 to 6.5 metres), requires a warmer temperatures of 18°to 36°C (64 to 97°F) and slightly more rainfall 86 to 130 inches (2,200 to 3,000 mm) per year than Arabica.
In terms of yield, Arabica produces less coffee per hectare (acre) than Robusta, making the cost of growing Arabica much higher.
Arabica coffee beans are have a slightly larger and elliptical shape than the smaller, more round Robusta beans.
Structural differences also exist between the beans, which may explain why both beans roast differently under identical conditions.
Due to their bitter taste, both caffeine and chlorogenic acid (CGA) are believed to act as deterrents for insects and animals.
Because Robusta contains about twice the concentration of both caffeine and CGA, it the plant much more ‘robust’ in the wild.
Arabica contains almost 60 per cent more lipids and almost twice the concentration of sugars than Robusta.
As a result these sugars play an important role during the roasting process in creating several key aromatic compounds, as well as contributing to the body due to its greater level of dissolved solubles.
Arabica is self-pollinating plant, meaning the plant will have fewer mutations and fewer variations throughout its life cycle as compared to Robusta.
Number of Chromosomes
Arabica has double the number of chromosomes at 44 than Robusta at 22.
All were tested for 16-OMC using the new nuclear magnetic resonance (NMR) technique, which employs radio waves and strong magnetic fields to obtain detailed information about a substance’s molecular composition.
‘It was immediately obvious using our test that there were several suspicious samples, producing results that were consistent with the presence of substantial amounts of Robusta – far more than would be expected through unavoidable contamination,’ said Dr Kemsley.
Two of the samples flagged as ‘suspicious’ were bought in the UK. One contained 1.6 per cent Robusta and the other 21.7 per cent.
Experts from the Quadram Institute in Norwich, formerly known as the Institute of Food Research, found a new method that takes only 30 minutes and is sensitive enough to detect just one per cent Robusta (pictured) in a blended coffee
Other UK samples had notable levels of 16-OMC but fell below the ‘suspicious’ threshold.
The findings not only affect consumers, but also undermine efforts to ensure that smallholders in developing countries are paid a fair price for the coffee they grow, said the researchers.
Giles Chapman, head of intelligence at the Food Standards Agency’s National Food Crime Unit, said: ‘We’re always keen to understand how scientific advances expand the range of tools which can be used to validate the authenticity of food products sold to UK consumers.
‘This piece of work has generated some interesting insights which we will be looking to explore further.’
The full findings of the research were published in the journal Food Chemistry.
Source: Read Full Article