BAYREUTH, Germany — There are plenty of food allergies which people suffer from. For those allergic to raw carrots, some believe cooking the vegetables will eliminate elements that cause a reaction. Scientists in Germany however are debunking this myth, saying it doesn’t matter if you heat your carrots up, they can still give you trouble.
Researchers at the University of Bayreuth find the allergen in carrots, called Dau c 1, can survive the extreme heat of the cooking process without completely breaking down. Dau c 1 is a mix of several structurally similar proteins. The German team exams these isoallergens while at temperatures as high as 203 degrees Fahrenheit. The results show the proteins are still capable of causing an allergic reaction once cooling down to about 77 degrees.
“The results of our research clearly suggest that sufferers who are sensitive to the carrot allergen should generally avoid eating carrots. Heating carrots does not destroy or only incompletely destroys the protein structures that can cause allergic reactions”, says Prof. Birgitta Wöhrl in a university release.
The study does note that heating carrots can make the severity of an eater’s allergies less pronounced. But overall, it won’t do much to ease the symptoms.
“The risk of allergy patients developing an allergic reaction arises not only when eating freshly cooked carrots or canned carrots. It also arises when carrot extract is added to food,” the study’s first author Thessa Jacob adds.
The resilience of the carrot allergen
Jacob says this is the first time allergies caused by Dau c 1 have been tested to this extent. Researchers also produced individual isoallergens in a lab using bacteria. The heat tests reveal natural Dau c 1 and the lab isoallergens both cause allergies once returning to a lower temperature.
Study authors add that the strength of carrot allergens don’t depend on just heat alone. The team finds acids also play an important role. A pH value (level of acidity) of three is typically found in the stomach after eating food.
Researchers says at this level of acidity, some allergen epitopes continue to survive despite being heated before the meal. Epitopes are the molecular receptors which trigger an allergy response in the eater’s immune system. Basically, carrot allergens can survive a good cooking and the acidity of your stomach, leaving allergy sufferers no relief from the orange vegetable.
The study appears in the journal Molecular Nutrition & Food Research.