State Changes: Zijn vs. Hebben
In Dutch, the perfect tense uses either hebben (to have) or zijn (to be) as the auxiliary verb. For verbs describing a change of state—like melting, thawing, or dissolving—the choice depends on how the verb is used.
When the subject undergoes the change of state itself (an intransitive action without a direct object), use zijn.
However, when the subject causes the change of state to happen to something else (a transitive action with a direct object), use hebben.
Notice how ontdooien (to thaw) is used in both sentences: the auxiliary changes based on whether the strawberry is thawing on its own (is) or something is thawing it (heeft).
Cooking It Down
This rule applies to many processes you'll encounter while cooking, such as boiling down (inkoken) or dissolving (oplossen).
The same pattern holds true for dissolving ingredients like pectin, which helps jam set.
Thickening and Melting
Here are a few more examples of these versatile verbs in action while making jam.
Similarly, sugar can melt on its own, or you can melt it.
Finishing Up
Once your jam has reached the perfect thickness, it's time to jar it.
Make sure to clean up any spills before letting the preserving jar (de weckpot) cool!