People who prefer their coffee strong and black are more likely to exhibit psychopathic tendencies, a new study suggests.

Scientists from Innsruck University in Austria examined the taste preferences of 1,000 people, and the results confirmed the hypothesis that people who prefer bitter notes like those found in black coffee and dark chocolate are more likely to exhibit signs of malevolent personality traits, such as "Machiavellianism, psychopathy, narcissism, and everyday sadism," researchers said, reported The Huffington Post.

Two groups of participants were asked to rate, on a scale of one to six, how much they like food and drinks that are either bitter, sweet, sour or salty. Participants then completed four personality tests that assessed their propensity for aggression, how manipulative they are, and examined specific traits associated with psychopathic tendencies.

Another test assessed the "Big Five" personality dimensions (extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience) for overall consistency checks.

Subjects answered questions like, "Given enough provocation, I may hit someone?" and "I tend to be callous or insensitive," according to Fox News.

The study's authors said that of the four tastes, someone's affinity for bitter foods - including beer, tonic water and even radishes - was the most accurate way to measure personality traits, suggesting that "how much people like bitter-tasting foods and drinks is stably tied to how dark their personality is."

"Regression analyses confirmed that this association holds when controlling for sweet, sour, and salty taste preferences and that bitter taste preferences are the overall strongest predictor compared to other taste preferences," researchers said. "The data thereby provide novel insights into the relationship between personality and the ubiquitous behaviors of eating and drinking by consistently demonstrating a robust relation between increased enjoyment of bitter foods and heightened sadistic proclivities."

On the other hand, people with more "agreeable" personality traits, such as kindness, more often disliked bitter tastes.

Researchers noted that the study does not answer the question of what makes someone enjoy particular kinds of foods, as there are many other factors involved in shaping those preferences. For example, it is unclear whether it is a biological or psychological mechanism, or a combination of both.

The study was published in the journal Appetite in late September.