Science Byte

Many fresh cheeses have aromas reminiscent of milk or cream, what’s causing that?

“Milky”, “creamy”, “milkfat”, and “sweet-coconut” are flavors people often attribute to different cheeses. Milky, being a “delicate” flavor, is often overshadowed by other more prominent flavors. For this reason, young/fresh cheeses are often the easiest to detect the milky flavor. Cheeses like ricotta, fresh mozzarella, and mascarpone are usually very milky tasting. Very young Cheddars, Colbys, and Goudas can also have a milky flavor.

While milky is difficult to attribute to one type of chemical compound, lactones are often thought to be a main creator of milky flavor. Lactones are cyclic compounds that originate from the fat portion of milk. They are created when milk is heated during cheesemaking. It is believed that the lactones formed in milk during cheesemaking are carried over to the final cheese. The various types of lactones created in cheese can range from a butterfat aroma, fruity aroma, or even a coconut aroma. Examples of milkfat lactones include: γ-Decalactone, δ-Decalactone, δ-Dodecalactone, and others. For those interested in the mechanism of formation for lactones read on!


Examples of lactones that can be found in cheese

Lactones are created primarily when milkfat is heated in an aqueous (watery) medium. Warm milk is such a place! If you recall from previous discussions, milkfat is found as triglycerides. Triglycerides are made up of long chains called fatty acids. These fatty acids get rearranged to form lactones. An illustrative mechanism is shown below.

lactone mechanism

Mechanism of lactone formation from fatty acids


While we often talk about flavors and aromas being caused by certain compounds, it’s important to remember that the unique taste and aroma of cheese is caused by a whole menagerie of chemicals. Cheese flavor is definitely a case of the whole being greater than the sum of its parts.