Sound is a very important sensory experience when eating different food products. Think about the crispiness of potato chips — you can clearly tell by sound cues, and the texture of the product, if it meets certain expectations that you have for the quality of the product. Similarly, squeakiness is something that many consumers expect when eating fresh cheese curds.
Squeakiness only lasts a few days to a couple of weeks after the cheese is made depending on how the curds are stored (i.e., room temperature, refrigerated) and served (i.e., warmed, cold). Therefore, when you eat cheese curds that are not squeaky, that is a good indication that the curds are not very fresh anymore which could be considered undesirable by many consumers.
A group from UW–Madison’s Center for Dairy Research, led by Rani Govindasamy-Lucey, is working on a project with the goal of extending the squeakiness shelf-life of fresh cheese curds. Maggie Becher, a PhD student in the Department of Food Science in Dr. John Lucey’s lab, has been working on this partly Hub-funded project. Becher has been exploring different analysis methods, including a collaborative method with an audiology lab on campus to monitor acoustic properties of squeakiness. Different manufacturing treatments are also being explored for the squeaky curds.
While most cheese curds are Cheddar curds, the extensive acidification from the starter cultures may weaken the protein matrix, thus interfering with the squeakiness longevity of fresh curds. Therefore, Lucey’s group took inspiration from another type of squeaky cheese from Finland — Juustoleipä (sometimes called “bread cheese”) — which does not include any form of acidification and includes a baking step after the cheese is made. This style of cheesemaking was applied to the research cheese curds (pictured below). The group is exploring the effect that these treatments have on reducing the protein breakdown of the curds throughout storage and correlating that to the changes in squeakiness and texture, which will provide insights into what causes the squeakiness and why it disappears.
Becher gives a summary of this work in the video below.