Catalyzes the isomerization of trans-2-decenoyl-ACP to cis-3-decenoyl-ACP. Most active with 10-carbon enoyl-ACP. Can also use 12-carbon enoyl-ACP as substrate, but not 14- and 16-carbon enoyl-ACP. (2E)-decenoyl-[ACP] = (3Z)-decenoyl-[ACP] Lipid metabolism; fatty acid biosynthesis. Homotetramer. Belongs to the enoyl-CoA hydratase/isomerase family.