Both agreed: It had the texture of meat, but the flavor still needs work.
The five-ounce burger — which cost more than €250,000 ($331,200) to make — was cooked in a frying pan by Chef Richard McGeown, who approached the Cultured Beef patty "like a traditional burger" despite it being a "little paler than normal."
Since the meat lacks blood cells, red beet juice and saffron were added to make the hamburger more pleasing to the eye.
The hamburger's creator, Professor Mark Post of Maastricht University, believes that in-vitro meat could end the impending food crisis and satisfy the world's growing demand for meat without destroying the environment or harming animals.
But does a test-tube burger live up to the real thing?
Rützler said she was expecting the burger to be more juicy.
The hamburger doesn't yet have fat, which is where most of the flavor comes from.
"It was crunchy on the top surface and hotter than I normally expect," Rützler said. The inside did not have an "intense meat flavor."
Schonwald was equally unsure about the flavor. "It's somewhere on the continuum between a Boca burger and a McDonald's burger," he said. Of the texture, he said it had a "cake-like quality."
Taste continues to be one the biggest technical challenges. "There's no meat scientist that can tell you which chemical composition of meat drives the tastes," Post said.