Blender to Unity, only import some meshes

Hi,

I'm making a small game in Unity that has a lot of low-poly assets. I like that Unity can read the .blend files, which lets me edit a mesh quickly in Blender and see an immediate change in unity without having to export the file each time. But, when I'm making Blender objects, I usually create a lot of meshes for reference and all of these are loaded into Unity as well, but I don't need them. Is there a way to limit which meshes Unity recognises?