On Thursday, Red Lobster fired back at YouGov's findings, saying that the seafood chain's actual results and internal research show the opposite is true. Same-restaurant sales have been positive in the second quarter and since the new menu's launch, Red Lobster spokeswoman Erica Ettori told CNBC.
That would mark a big improvement from when same-restaurant sales slid 5.6 percent in its last full quarter under the Darden Restaurants umbrella.
"[O]ur guest satisfaction is the highest it has been in three years," Ettori said. "Additionally, sales of the new items are exceeding expectations, which demonstrates the menu is resonating with guests. We couldn't be more pleased with the response our new menu is receiving from our guests."
In YouGov's poll, fewer people said they would consider dining at Red Lobster the next time they are choosing a restaurant to visit. On Tuesday, just 26 percent of people said they'd think about going to Red Lobster—down from nearly 36 percent the day before the new campaign launched. (The chain peaked this year at 37.4 percent in late February.)
"What we're not seeing in the first month since that new menu launched is any positive impact on brand perception," said Ted Marzilli, CEO of YouGov BrandIndex.
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"Right now it doesn't look like it's resonating with consumers," he added.
Still, this portion is much higher than the casual dining average of 14 percent.