Probably empty casks; or they will be empty by the time the teams try to find the five with clues. Could this be a DETOUR - load sugar cane or drink the rum (well actually find the clue in the rum)? Both in Costa Rica?
The Linzs are shown doing both tasks.
I watched closely and picked up some things:
1. When the Linzs are traveling down the river in the raft they jump into the water into a waiting canoe and 5 canoes are there (they are in the lead at this point??). Then they are shown bailing water out of the canoe.
2. Godlewskis appear to be wearing different clothes for race cars and stunt plane even though they are both in Arizona.
3. Linzs are wearing the same clothes for sugarcane and barrels (confirms Costa Rica for barrels)
4. Teams shown doing tasks:
Linzs are shown on 4 tasks -- rum barrels, sugarcane, river canoe, and stunt plane
Paolos are shown on 3 -- swimming, sugarcane, and stunt plane
Godlewskis on 2 -- race cars and stunt plane (reading clue though could be another voiceover)
Weaver 1 -- race cars
Bransens 1 -- stunt plane