Went to fetch my lunch out of my pannier today to find my hands covered in an oily substance...
Oh dear. Salad dressing EVERYWHERE - salad dressing I had made myself with the correct 3:1 oil:acid ratio, so pretty damn oily. Somehow the sealing lid on the box, with a rubber gasket and 2 snap-shut clips for the sides had failed to do its job, as had the plastic bag that the box was wrapped in.
Fortunately (or not) I had a spare longsleeve merino rolled in the bottom of the pannier which had absorbed most of the oil, and my valuables were rolled in a small, waterproof stuff sac.
The white Renner-Flanders musette courtesy laidback) which the spare tubes and whatnots are rolled in had absorbed most of the balsamic vinegar and was a nasty, blotchy shade of brown.
The positive was that being an Ortlieb, once home I could remove 9 screws to release all the plastic stiffening components and separate the inner pocket from the outer, and was left with a big cordura sack that I could invert and give a proper scrubbing. The inner needed some patching anyway, so has been trimmed to a lock-friendly shape and size, re-sewn and washed. Goos as new.