The food industry is changing faster than ever before, said Mondelez's outgoing CEO Irene Rosenfeld.
"I mean, we have seen the most profound changes in the consumer, in the customer base, in the channel penetration, in our competitive actions. And as a result, it's been probably the magnitude and the speed of those changes is bigger than any I have seen in my career," Rosenfeld told CNBC's"Squawk on the Street" on Tuesday.
Despite the changes, Rosenfeld said she's still confident in the food industry and Mondelez. She has led the global snack powerhouse since 2012 when it was spun off from Kraft, where she served as CEO since 2006.
Mondelez, which makes brands such as Oreo cookies and Ritz crackers, and Big Food companies' scale is critical in today's global economy, she said. But companies still need to keep their ears to the ground.
Wall Street has hammered food companies facing changing consumer preferences, a competitive retail environment and growing e-commerce platforms like Amazon. Rosenfeld told investors on Tuesday that today's challenges are radically different from other "cosmic changes" that occur every few years.
In Rosenfeld's last quarter as CEO, Mondelez posted earnings of 57 cents per share, beating Wall Street's predicted 54 cents per share. Revenue grew 2.1 percent from the year-ago quarter, reaching $6.53 billion and surpassing estimates of $6.45 billion.
Shares of Mondelez climbed 5.2 percent on Tuesday.
Rosenfeld told CNBC the recovery of emerging markets' economies and stabilizing foreign exchange helped Mondelez in the quarter. She touted growth on both the snack food company's top and bottom lines as proof that its focus on margins and cost-cutting is paying off.
"At the same time, we always understood that someday, these markets would come back, and we wanted to make sure that we would be well-positioned when that happened. We have invested in our brands, our routes to market, and it's starting to pay dividends," she said. "I feel very good that the business is poised to continue the momentum that we're starting to see."
Rosenfeld's successor, Dirk Van de Put, will take over as CEO on Nov. 20. He comes from McCain Foods Limited, a privately held Canadian company known for its french fries.
Rosenfeld's advice to Van de Put? It's all about profitable growth.
"I think we've got the fundamental foundation in terms of our margin structure setup. Obviously, we'll continue to see opportunities there," she said. "But the biggest opportunity now is to figure out which are the best bets to place so that we can further accelerate our top-line growth.
"I truly believe that the combination of a strong top line together with a strong bottom line is what makes for a sustainable business."