There are several ways to make the plant particles as fine as possible.
- The pureeing process itself is a physical crushing or shearing that breaks the plant tissue into pieces and liberates thickening molecules from them. Blenders and mortars are the most effective tools for this; food processors slice rather than crush. Producing a fine puree can take some time even in a blender, several minutes or more.
- Straining through a sieve or cheesecloth removes the large particles, and forcing the puree through a fine mesh breaks large particles into smaller ones.
- Heating softens cell walls so that they’ll break into smaller pieces, and shakes loose long-chain carbohydrates from the cell walls and gets them into the watery phase, where they can act as separate starch and gelatin molecules do.
- Freezing a puree and then thawing it causes ice crystals to damage cell walls, which can help liberate more pectin and hemicellulose molecules into the liquid.