Peptides created during cheese ripening are critical to the rich, full-bodied flavor that defines aged cheeses, a sensation known as kokumi. Now, researchers at the Leibniz-Institute for Food Systems Biology at the Technical University of Munich have made a leap in analyzing these essential peptides, developing a faster, more precise method to measure them—the findings for which were published recently in Food Chemistry. This breakthrough could reshape how we predict and enhance the flavor of cheese.

Through the analysis of over 120 cheese samples, the research team has not only refined peptide measurement techniques but also built a comprehensive database. This tool can be used to predict how flavors will develop as the cheese matures, offering new insights into the art of cheese-making.

What Is Kokumi?

Kokumi, a term from Japanese, describes a full-bodied, lingering taste experience. It’s a signature of aged cheeses, primarily driven by gamma-glutamyl dipeptides—small molecules formed from a bond between glutamic acid and another amino acid. Not all dipeptides contribute to kokumi, however; only gamma-glutamyl dipeptides have this effect, while other types, like alpha- or X-glutamyl dipeptides, do not.

This complexity presents a challenge for food scientists. The structural similarities and diverse flavor contributions of these molecules have made them difficult to analyze—until now.

A New Method for Analyzing Cheese Flavor

The team, led by principal investigator Andreas Dunkel, has developed an ultra-high-performance liquid chromatography-mass spectrometry method that can, for the first time, precisely measure all 56 variants of gamma-glutamyl dipeptides in just 22 minutes. The method also boasts an optimized sample preparation process that allows for the analysis of up to 60 cheese samples daily.

“Our method is not only faster and more efficient, but it’s also highly reliable, capable of detecting even the smallest concentrations of these peptides,” said Sonja Maria Fröhlich, a doctoral student at the Leibniz Institute and the study's first author.

To further test the method, the team applied it to 122 cheese samples from Europe and the U.S., with ripening times ranging from two weeks to 15 years. The results confirmed that gamma-glutamyl dipeptide concentrations rise steadily as the cheese matures.

The Surprising Role of Mold Cultures

One unexpected finding was the influence of mold cultures on flavor development. Both blue and white mold significantly accelerated the concentration of gamma-glutamyl dipeptides, even in cheeses with shorter ripening times. This suggests mold could play a key role in enhancing the flavor of cheese without needing extended aging periods.

“The concentration profiles we’ve determined at various stages of ripening will serve as the foundation for future predictive models,” explained Andreas Dunkel. “These models could help monitor flavor development in real-time, shorten ripening periods, and even guide the creation of new, plant-based cheese alternatives with high consumer acceptance.”

Toward Sustainable Food Production

Veronika Somoza, director of the Leibniz Institute, added, “In line with our interdisciplinary food systems biology approach, one of our aims is to combine these analytical insights with bioinformatics to create predictive models that support sustainable food production. This is the broader goal of our research.”

This breakthrough offers more than just a better way to analyze cheese—it opens the door to new innovations in food production, allowing scientists and producers to predict, enhance, and potentially transform the flavors of tomorrow's cheeses.