Chocolate's irresistible aroma comes from a mixture of molecules that give it that unmistakable smell and taste that many of us crave.

However, Belgian researchers claim that some of these same compounds can pose health risks if present in high quantities.

In simple terms, what makes chocolate taste so good can also mix with other ingredients and damage your DNA.

In a recent study, the team of researchers found that while chocolate contains safe levels of certain molecules called α,β-unsaturated carbonyls (Cβ=Cα-C=O), some pastry products, such as crepes and cakes, have much higher concentrations of a particularly worrying carbonyl: 2(5H0)-Furanone.

The study's conclusions were presented in an article published this Wednesday in the Journal of Agricultural and Food Chemistry.

These carbonyls are formed during the roasting of cocoa beans and react with other ingredients at high temperatures. Although many are considered safe, 2(5H0)-Furanone is potentially genotoxic, which means it can damage our DNA when consumed.

According to Science Daily, the safety concerns raised by this compound have even led to a ban on its use as a food additive in the European Union.

To better understand the origin of these carbonyls and whether they pose any real health risks, the researchers carried out experiments on samples of various chocolates and other sweets.

Chocolate’s tasty flavors might pose a risk in other desserts
What makes chocolate taste and smell so delicious? Chemistry, of course! A variety of molecules work together to create that unmistakable aroma, but those same molecules might carry some unwanted health effects if there are too many around. While many of the compounds appeared in chocolate in low enough concentrations to be safe, higher amounts were found in some baked sweet treats.
ScienceDaily

First, they made their own chocolates in the laboratory, analyzing them at every stage of the process. They found that carbonyls formed during the roasting of the beans and after the addition of cocoa butter, but remained at safe levels in the final chocolate products.

They then bought 22 different commercial pastry products, such as crepes, waffles, cakes and cookies - some with chocolate, some without. When they analyzed 10 different carbonyls, they detected lower levels of nine of them compared to the chocolates produced in the laboratory.

However, 2(5H0)-Furanone was present in very high quantities in the crepe and cake samples - up to 4.3 mg per kg of food.

With a recommended limit of only 0.15 micrograms per person per day for genotoxic substances, consumption of these pastry products could potentially exceed this safety limit.

Interestingly, the levels don't seem to correlate with the amount of chocolate, suggesting that this carbonyl was probably formed during the cooking process itself.

Apparently, eating chocolate is safe... but chocolate cake not so much.