Problem with the wash machine is your hammock turns into a giant water filled bucket/mess when you try to pull it out of the washer. Hand washing works fine and cleans up well, without twisting and turning the stitching. I wouldn't want to tear up my mosquito netting trying to get a stain or smell out.
Try baking soda, sprinkle some on and wrap it up and stick it in a paperbag for a day or two. Should absorb the smells, works in the fridge.
I'm also packing a dryer sheet in with my tarp and hammock. Kills the static and freshens things up. And the bugs don't like the smell of dryer sheets.