Ginger has a substance called gingerol, which contributes to the pungency level. It's also the easiest to manipulate through cooking methods and can be transformed into several taste sensations. When dried, it is transformed into shogoals, which are twice as pungent. And when ginger is cooked, some of the gingerols and shogoals are transformed into zingerone, which is not that pungent at all, approaching a sweet and spicy flavor. This is why dried ginger is always stronger than fresh, and why crystallized or candied ginger is sweet yet spicy and very palatable.