Applying prop antifoul (underwater!!)

[pcatterall]

　
Just thinking about the particulary bad fouling we get on our prop in Cagliari.

I know that befre we go anywhere we will have to scrape a mass of crustations from our prop and that if we leave the boat for any time the growth will be back with a vengance.
I know that some people have resorted to tying plastic bags around the prop and then ( presumably) removing before setting off.
Could somethinglike lanoline or grease be applied after scraping off ? This should at least give protection until you use the engine again?
Any ideas please

 

[ghostlymoron]

Some people use cow udder cream but I don't know how you would apply it under water.