Roasting unlocks the aromatic coffee flavours from raw beans.
Grinding exposes more of the bean, so more is infused into the hot water percolating through to make a drink.
You get more of a whole bean flavour with Kenco Millicano as it contains 15% finely milled roast and ground coffee.
Brewing & freeze-drying
When making instant coffee, ground coffee is brewed and then freeze-dried to capture as much flavour as possible.
Getting from bean to cup and with as much flavour as possible
At each processing stage some of that fresh- roasted flavour is inevitably lost.
Ground coffee exposes more surface area, losing flavour quicker to the air than whole beans. Instant faces the same issue with the added factor that it has already been brewed during manufacture.
Freeze-drying, foil-sealing and good packaging mitigate flavour loss but bean-to-cup machines are what will deliver coffeehouse quality flavour.
With bean-to-cup machines, right up until seconds before the drink is served, the only process that the beans has undergone is roasting. That makes for fresh, full flavour.