WordNet sense 1 (resembling starch):

amylaceous, amyloid, amyloidal, starchlike

WordNet sense 2 (composed of or covered with particles resembling meal in texture or consistency):

grainy, granular, gritty, mealy, coarse-grained, granulose

WordNet sense 3 (of textures that are rough to the touch or substances consisting of relatively large particles):

coarse, harsh