This'll probably be an xpost with a faster typer, but you can use coffee filters / very fine nylon mesh (you can get from ebay microscope supply sellers usually) or even filter through several layers of muslin cloth (like jelly cloths or jelly bags used in jam-making - I fold mine a few times then sit it in a fine mesh sieve).
As you are using organic materials, make sure everything is scrupulously clean (sterilise with Milton or Campden tablets for utensils, cloths and so on): PG will inhibit mould growth, but not necessarily stop it altogether.