In the context of coffee, "ground" refers to ground coffee, which means coffee beans that have been ground into small pieces or a powder, ready for brewing. It doesn't refer to "地面" (the ground) in this case. So, in your sentence:
"mild to moderate intake of ground, instant and decaffeinated coffee" * "Ground" refers to brewed coffee made from ground coffee beans. * "Instant" refers to coffee that is soluble and dissolves in water. * "Decaffeinated" refers to coffee with most of the caffeine removed. This means the sentence is talking about different types of coffee and how they can be part of a healthy lifestyle.

In this sentence, "ground" refers to - ground coffee- which is coffee beans that have been ground into small particles for brewing. It's different from instant coffee. Tip: When you see "ground" in a coffee context, think of -ground-up coffee beans-

"Ground" is an adjective here describing "coffee"—it's the past tense of the verb "grind." The other two adjectives in that sentence modifying "coffee" are "instant" and "decaffeinated." "Ground" coffee refers to the kind that requires a brewing process to prepare, as opposed to simply adding hot water ("instant" coffee). "Decaffeinated" is coffee from which the caffeine has been removed.

Ground here refers to the verb to grind so ground coffee is the result of grinding the coffee beans into a powdery form.