By: Jaclyn Kalina
When trying to keep food items cool for picnics and such, many turn their heads to dry ice or cool packs to do the job. However, according to recent studies, mushrooms are the real solution due to their properties. Since mushrooms contain a lot of water, they release it in a fungal form of sweating which lower the temperature, thereby making them cooler. The question is: how did scientists arrive at these conclusions?
It all started during the COVID-19 pandemic when Johns Hopkins university microbiologist Radames Cordero was testing out his new camera while strolling through the woods. The camera was a thermal camera which records heat as images. Alongside Arturo Casadevall, Cordero wanted to use the camera to see the dark pigments of some of the fungi and how it influences their surface temperatures. All of the mushrooms he took pictures of were cooler than their surroundings regardless of their color. They later took these finding to a lab where they found that some species, such as the brown American star-footed amanita, was around 1 to 2 degrees cooler than their surroundings, but the mushroom named Pleurotus ostreatus was almost 6 degrees cooler. They also discovered that a myriad of other molds and yeast were cooler than their surroundings as well.
Based on the work in the lab, “this phenomenon is a widespread feature of the fungal kingdom” according to Cordero. The reason why the mushrooms possess this ability is due to their complex gill architectures on the undersides of their mushroom caps. These structures increase the surface area for cooling and allows water to evaporate from the fungi, just like we sweat on a hot day. It is unclear, though, why fungi have this ability and how it benefits them. Some scientists speculate that it may aid in the development or release of spores from the mushroom caps, or simply just because they prefer to exist in lower temperatures.
These findings hold value in terms of keeping food items cold. Coredero and Cadadevall put two air holes in a Styrofoam packing box containing button mushrooms and then installed a computer exhaust fan in one hole to draw air through it. They put the box into a larger Styrofoam container and with the fan on, the container’s temperature dropped 10 degrees (Celsius) within 40 minutes. You cannot necessarily freeze water with the mushrooms, but you can easily keep a “six-pack and lunch chilled for a quick picnic” (Casadevall). Another fun advantage is that if you’re a mushroom fan, you can snack on the mushrooms afterwards!