The goalkeeper joined the Reds this month from Roma for £66m.
“Yes, it was a big deal for Roma, they had a record fee and they were happy," Alisson said.
“And I'll work very hard to make sure it's a good deal for Liverpool too, which is more important. I know that Salah was (thought) a good deal for Roma, but now people say it is a good deal for Liverpool.
“I want to work hard to ensure that yes, people say they paid a (bargain) price for me too, eventually."