Coffee is an essential beverage in many people's daily lives, yet discussions surrounding its safety have never ceased. As a fungal metabolite that may contaminate coffee, does ochratoxin A cause health damage to long-term drinkers? Based on "Scientific Interpretation of Hot Topics of Public Concern," written by experts organized by the Science Popularization Department of the China Association for Science and Technology and the Chinese Institute of Food Science and Technology, this article systematically reviews the sources and toxicity of ochratoxin A and its contamination status in coffee, and, combined with dietary exposure data from European populations, analyzes the actual health risks of drinking coffee. At the same time, in light of the characteristics of coffee consumption in China, it provides a scientific and rational assessment conclusion to help coffee lovers eliminate unnecessary concerns and enjoy every cup of coffee with peace of mind.
In recent years, food safety has consistently been a focus of great concern for the general public, and food safety incidents exposed by various media have emerged one after another. In the face of such complex and diverse information, how should we rationally view food issues? To this end, the Science Popularization Department of the China Association for Science and Technology and the Chinese Institute of Food Science and Technology jointly organized experts to compile "Scientific Interpretation of Hot Topics of Public Concern," providing professional answers on the topic of "food safety," aiming to help the public correctly understand food safety risks and alleviate unnecessary panic.
What exactly is ochratoxin? Does long-term coffee drinking harm the body?
The explanation given by experts is: Ochratoxin is a metabolic product of toxic fungi, produced by various fungi such as Penicillium verrucosum, Aspergillus ochraceus, and Aspergillus carbonarius. It is a group of toxic metabolites with similar structures that mainly damage the kidneys of humans and animals. It includes four compounds—A, B, C, and D—among which ochratoxin A (OA) is the most toxic, most closely associated with human health, and most widespread in contaminating crops. This substance has significant liver toxicity and kidney toxicity, and also has potential teratogenic, mutagenic, and carcinogenic effects. Because the fungal species that produce ochratoxin A are extremely widely distributed in nature, many crops and foods—such as cereals, dried fruits, grapes and wine, coffee, cocoa and chocolate, Chinese herbal medicines, seasonings, canned foods, edible oils, olives, soy products, beer, and tea—may be contaminated by ochratoxin A. It is also one of the main contaminants in the diets of some European countries.
As far as coffee is concerned, both the contamination rate and contamination level of ochratoxin A are relatively low, and only a few countries have established limit standards for ochratoxin A in coffee. Many countries around the world with coffee-drinking habits, especially European countries such as the United Kingdom, Germany, Denmark, Switzerland, Sweden, the Netherlands, and Spain, as well as the United States, Japan, and Brazil, have conducted extensive research on the contamination status and population exposure of ochratoxin A in coffee, and the results consistently show that both the contamination rate and contamination level of this toxin in coffee are low. One study tested 116 instant coffee samples collected from different countries and different companies, and the results showed that: in instant coffee made from pure coffee beans, the ochratoxin A contamination level was extremely low, averaging only 1.1 μg/kg; while in instant coffee mixed with coffee husks, the average contamination level of this toxin was slightly higher, at 5.9 μg/kg, with the highest contamination level reaching 15.9 μg/kg. At present, more than 40 countries worldwide have set limits for ochratoxin A in grains and their products, fruit wines, dried fruits, and infant foods, but only a few countries have established limit standards for this toxin in coffee, including Greece, Bulgaria, Cuba, Hungary, Uruguay, Singapore, and Italy, with limit values ranging from 2.5 to 50 μg/kg.
The risk of drinking coffee posing a hazard to human health is extremely low. Ochratoxin A is one of the main contaminants in dietary exposure in European countries, so it is most appropriate to use the cereal intake and ochratoxin A contamination levels of European countries provided by the Global Environment Monitoring System – Food Contamination Monitoring and Assessment Programme (GEMS/Food) to conduct population exposure risk assessment. According to European dietary characteristics, the ochratoxin A contamination data in cereals reported by various countries were summarized and weighted averages were calculated. Based on this principle, the total average weekly intake of ochratoxin A for a European adult weighing 60 kg is 45 ng/kg.bw, of which 25 ng comes from cereals, 10 ng from wine, 1.5 ng from pork, and the amounts of ochratoxin A from grape juice and coffee are roughly equivalent, both at 2–3 ng, with another approximately 1 ng from other foods. From this result, it can be clearly seen that although many countries have detected ochratoxin A in coffee, because the contamination level is low and coffee intake is far lower than that of foods consumed in larger quantities such as cereals and animal-derived foods, coffee is not the main source of dietary exposure to ochratoxin A in countries with coffee-drinking habits. In other words, the risk of drinking coffee causing harm to human health is extremely low.
Considering that coffee currently sold in China (including raw materials and products) mainly relies on imports, and that compared with tea and other beverages, coffee has not yet become a major beverage for the Chinese population, with relatively low consumption, and referring to the contamination levels of ochratoxin A in coffee abroad, the risk of ochratoxin A exposure through coffee in the Chinese population is low, and the possibility of adverse health effects is small, so consumers need not worry excessively.
The above content is compiled by CoffeeHunters, a coffee news website.
