Learn French: L'extrait de jasmin est très floral. - The jasmine extract is very floral.

We use de without the definite article because jasmin acts as a descriptive category or ingredient here. It tells us what kind of extract it is, similar to a compound noun in English (jasmine extract), rather than meaning the extract of a specific jasmine plant.

How would this sentence change if we were talking about multiple extracts?

It would become Les extraits de jasmin sont très floraux. As a B2 refresher, remember that most masculine adjectives ending in -al change to -aux in the plural.

Is there a reliable way to remember the gender of extrait?

Yes! Nouns ending in the suffix -ait are almost always masculine in French. Other common examples you likely know include le lait (milk), le portrait (portrait), and le souhait (wish).