Instant coffee is made by brewing coffee and then removing water so that the resulting soluble material can be reconstituted. Freeze-drying and spray-drying are different production approaches; neither can be identified reliably from a simple assumption about whether the beans were Arabica or Robusta. Read the product description rather than inferring the entire process from crystal color or shape.
Prepare it with a measured amount of coffee and water, using the package recipe as a starting point. Stir until dissolved, then judge the concentration before adding milk or sugar. Instant coffee does not need to pass through a drip filter or remain in a French press like ground beans. If preparing an iced drink, dissolve it in a small amount of suitable water before adjusting the final milk, water and ice quantities.
Compare products at the same serving strength and with the same additions. A sweetened premix is a different recipe from plain soluble coffee, and decaf is a separate product attribute. Store the container tightly closed as directed. The convenience is easy to assess directly, without relying on a single invention story or promising that every instant coffee will resemble freshly brewed espresso.

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