Before refrigerators, people had to be creative about keeping food fresh. Methods like salting, pickling, smoking, and canning helped to preserve meat, fruit, and vegetables. But it was hard to preserve dairy products. ​

Some people built springhouses to keep their milk fresh. Springhouses were box-like structures built on top of cold springs. The cool running water would keep the dairy products cool too. ​

Other people came up with other ways to cool their milk. One bizarre method was used in Russia. It involved frogs.​

How could a frog possibly keep milk cool and fresh? People believed that the cold-blooded temperature of the frogs would transfer to the milk. They threw the frogs into the buckets of milk and hoped for the best. ​

We now know that the frogs were not cold enough to actually cool the milk. However, the method was used because it did help the milk stay fresh for longer. How? ​​

In 2012, scientists discovered special chemicals made by the skin of brown Russian frogs. The chemicals contained antibacterial compounds. They found over 76 of these compounds on the frogs’ skin.​

These chemicals would have gotten into the milk. They would have made the milk safe to drink for a longer time. They would have allowed Russian people to enjoy milk even without refrigeration. ​

Putting frogs into milk might sound gross now, but it was effective in the time before refrigerators. We are finally learning the science behind these old methods. Strange but smart!​