I had a "new" to me roll of Colorfabb translucent green. The guy I bought my printer from threw it in the deal. It had a manufacture date of 2011, but was still vacuum sealed. It was cracking and brittle.
I heated up a big pot of water to 70°C, took it off the heat. Placed the whole spool on a potato masher, and lowered it in the water for 30 seconds. Left it to cool and dry and it's printing fantastic.