Coffee manufacturers have introduced measures to avoid the development of Ochratoxin A and closely monitor levels of acrylamide and furan in the final coffee product.
Many studies have considered the possible effects on health of the compounds formed during processing, and some of this research is summarised below.
Ochratoxin A
Ochratoxin A (OTA) is a mycotoxin produced by mould that can develop on badly stored coffee beans. OTA can be found in a number of different foods including cereals and dried vine fruits when they are stored under humid conditions20.
Today, ‘Good Agricultural Practice’ in coffee producing countries has enabled effective controls to be put in place at source, ensuring correct storage of coffee beans to avoid the development of Ochratoxin A. EU regulation also control levels of OTA in coffee, thus eliminating the concerns associated with its presence in coffee beans and finished coffee21.
In 2020, The European Food Safety Authority (EFSA) in its ‘Risk assessment of ochratoxin A in food’, concluded that ‘possible associations between OTA exposure and kidney disease, bladder or hepatocellular cancer have been investigated in epidemiological studies, but it is not possible to establish a causal link between exposure to OTA and adverse effects in humans’22.
A 2022 meta-analysis of the concentration and prevalence of OTA in coffee products suggested that its presence can vary, and the authors advise that monitoring and control plans should be carried out in different countries to account for the variabilities seen23.
For further information from the European Coffee Federation’s ‘Code of Practice for the Prevention of Mould Formation’, click here.
Acrylamide
In June 2015, EFSA issued a scientific opinion which found that acrylamide in food may potentially pose a health risk, namely an increased risk of cancer24. The conclusion was based on animal studies as EFSA stated that evidence from human studies is limited and inconclusive. A previous review has also suggested that epidemiologic studies of dietary acrylamide intake have failed to demonstrate an increased risk of cancer in humans25. In its review of coffee and cancer, published in June 2016, the International Agency for Research on Cancer (IARC) classified coffee into Group 3 for agents ‘not classifiable as to carcinogenicity to humans’26. After thoroughly reviewing more than 1,000 studies in humans and animals, IARC found there was inadequate evidence for the carcinogenicity of coffee drinking overall26.
A dietary intake survey from 20 European countries suggested that European adults have an average daily acrylamide intake that ranges from 0.14 to 1.31 mg/kg of body weight. Whilst coffee is a contributor to AA intake, baked goods and crisps contribute higher amounts to overall intakes in some countries27.
A 2020 review suggested studies which evaluate the effects that acrylamide in foods has on human health revealed a general lack of association between dietary acrylamide exposure and the incidence of different cancer types. They also noted that the consumption of coffee is associated with a decrease in the overall incidence of cancer in humans. The authors suggest this paradox illustrates the risk of evaluating an individual molecule independently of its complete food matrix, which may have other components that completely override the effects of the considered molecule28. A further study, supported these findings concluding that the data does not support an association between dietary acrylamide exposure and cancer types29.
Health authorities have not advised people to stop consuming coffee or any food due to occurrence of acrylamide. In November 2017, the European Commission introduced regulation to reduce the presence of acrylamide in food, including coffee products30.
Furan
Furan and methylfurans form naturally during heating or cooking and are present in a wide variety of foods and beverages, including infant cereals, baby food in jars, breakfast cereals and coffee. In coffee, furan is naturally formed during the roasting process. Furan is likely to have been part of the human diet for thousands of years, as it can be formed through traditional cooking methods.
Several studies indicate that furan levels significantly decrease during coffee brewing, as the compound is highly volatile and evaporates readily31-34.
The levels of furan in coffee are monitored throughout Europe and reports are published regularly by EFSA35.
The International Agency for Research on Cancer (IARC), in its review of coffee and cancer published in June 2016, classified coffee into Group 3 for agents ‘not classifiable as to carcinogenicity to humans’. After thoroughly reviewing more than 1000 studies in humans and animals the IARC found there was inadequate evidence for the carcinogenicity of coffee drinking overall26. In addition, the IARC concluded that the research suggests an inverse association between coffee consumption and liver cancer26.
Regulatory bodies have previously examined furan, but to date have not established limits in food or beverage products. In 2017, EFSA published its scientific opinion on the risks for public health related to the presence of furan and methylfurans in food36. EFSA’s scientific opinion will help EU and national bodies decide whether further research is needed.