Fullbean Coffee Resources - Tennis Ball Saver

Tip for Home Coffee Roasters

The official purpose of a tennis ball saver is to hold tennis balls in a cannister at 14 pounds of pressure so that they retain their bounce.
However, they can also be used to increase the crema of fresh-roasted coffee beans.
Immediately after the beans have left the roaster and cooled to room temperature,
place them inside the tennis ball saver and screw the two halves of the device together to pressurize.

Fresh-roasted coffee typically off-gasses for up to two days after roasting.
By placing the beans in a tennis ball saver, the gases are trapped and reabsorbed by the beans.

Caveat; Many sources claim that coffee should be allowed to off-gas for varying amount of time ranging from 24-72 hours. Following these guidelines would countermand the idea of pressurization in a ball saver.
Experiment and decide for yourself.

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