Crispness of beer on the palate (besides carbonation)… ::)…well?
I’ve heard rice.
Water Chem. … sulfate, carbonate, iron, and many other minerals
Grain Bill … some grain flavors linger, others are more crisp (carmel vs pilsner malt for example) Also, If you are using a lot of types of grain in a single recipe, try backing it off to two or three grain types only.
Hops … oil content/ratio of Humulone, Cohumulone, Adhumulone, lupulone, essential oils, etc can vary among types, some are crisper, others less so.
Each one has an effect and can add crispness or leave a little more weight on the palate.
Sometimes, just adding some sugar in place of malt (keeping the same OG, though) will lighten a beer and make it crisper.
I have done each of these to tune a beer to make it lighter and/or crisper on the palat.
and high attenuation (high fermentability of wort and highly attenuating yeast and lots of it).
Pitched at the right temperature, oxygenated, and with a temperature controled fermentation. Had to add that.
I am convinced that yeast is the most influential and critical ingredient to making outstanding beer.