The days are getting shorter and colder, and the leaves are beginning change and fall. Across the East Coast, apples are ripe and ready to pick! Some of these apples are eaten whole, while others are processed into countless apple products, like apple cider. More than just a tasty fall treat, apple cider is also a feat in engineering. 

How do apples become cider? 

Cider is made by squeezing the juice out of ground-up apples. But imagine having to do that by hand; it would be really hard! That’s why many cideries use an apple press, which is a large machine that uses mechanical engineering to make a tough job easier. There are many types of apple presses, like a hydropress, which uses hydraulics to make the job easier.

Hydraulics is a way of using liquids, like water, to make things move or lift heavy stuff. It works by pushing liquid through a closed space, like a tube, which creates pressure that then moves something, like a press to squish apples! 

To better understand how hydraulics in a hydropress works, think about a water balloon. Imagine that you are holding a water balloon and squeezing it to push the water in different directions. You are pushing liquid in a closed space (the balloon), which creates pressure that stretches the balloon in a specific direction. This same exact process is used in a hydropress! 

In a hydropress, ground-up apples are placed in a strong basket with lots of little holes in it, and then a water bladder (think of a very strong water balloon) is placed into the basket with the apples. As the water bladder is filled, it presses out against the apples, squeezing them to release the juice, which then drains out of the basket through the holes. 

Hydraulics in Your Life
Hydraulic machines are all around us! Car brakes, construction diggers, and even some amusement park rides use hydraulics to make big jobs easier. Anytime you need to lift, push, or squeeze with super strength, hydraulics might be at work. Can you think of other times in your life where hydraulics might be helpful?

Want more?
If you enjoy learning how everyday things, like apple presses, use engineering, you’ll love our Mechanical Engineering Makerspace program. Come explore, build, and test your own creations while learning the same problem-solving skills engineers use in the real world!

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