Coffee capsule

A single-serve coffee container is a method for coffee brewing that prepares only enough coffee for a single portion.

Single-serve coffee containers can both reduce the time needed to brew coffee and simplify the brewing process by eliminating the need to measure out portions, flavorings, and additives from large bulk containers. They can also help to keep the unused product fresher by individually packaging portions separately without exposing the entire supply batch to air and light. Paper coffee pods can be functionally identical to plastic and metal coffee capsules, if the paper pods are individually sealed in separate bags.

Several different systems exist:

Photo of coffee bag manufactured by Folgers

A paper coffee bag by an unknown manufacturer - E.S.E. (Easy Serving Espresso Pod)

The plastic and metal coffee capsules typically are used in a non-removable receptacle on the brewing device. The capsules have an outer ring or rim that stays dry during use, allowing for removal and disposal after use without getting the user's hands wet or sticky. Handling of a used moist coffee pod is not necessary if the brewing device has a removable filter tray. This tray is removed after brewing and inverted to eject the used coffee pod.

Coffee pods, bags, and capsules can be sized for individual or multi-serving portions. In food service businesses, pods and capsules used with automatic brewing can help to provide consistency of product strength and flavor for customers.

Paper coffee pods such as those used in Easy Serving Espresso Pod or Senseo machines have the benefit of being a fully biodegradable product that can decompose naturally, while plastic and metal capsules such as those used in Keurig or Nespresso machines either aren't recyclable, or require additional processing to separate the plastic/metal container from the organic waste products.

Many capsule machines specifically warn the user to not disassemble the machine or put their fingers inside the capsule receptacle, as the devices commonly use sharp razor-edge tubes or prongs for piercing the coffee capsule during use.

Different single-cup systems are not interchangeable; some systems force machine owners to buy capsules from a single company (usually the patent owner), locking the machine owner into a single source of coffee. Coffee pods are made by a variety of manufacturers and are interchangeable between brand of pod and model of pod brewer most of the time.

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Wikipedia