Kraft has struggled to keep up with the changing consumer tastes in recent years, and in November it fired most of its advertising agencies amid slowing sales and declining volume.
The following month, it replaced CEO Tony Vernon, who led the company for two years, with its board chairman, John Cahill, whose experience includes a tenure at private equity firm Ripplewood Holdings
Kraft's brands are currently focused in the United States, so combining with Heinz provides a platform for international distribution, Erin Lash, senior equity analyst at Morningstar, told CNBC.
Lash said she will be looking for guidance on cost savings that 3G and Berkshire Hathaway expect the deal to generate, as well as signs for how the partners will handle the mix of brands in the portfolio.
"Kraft continues to operate with still some lackluster brands like Jell-O that they've been unable to turn around despite several attempts to do so," she said on "Squawk Box."
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In addition to Jell-O, the company has struggled with other high-margin, heavily processed foods, including Velveeta cheese, Crystal Light and Kool-Aid beverages, and Macaroni & Cheese. Kraft's Oscar Meyer and Philadelphia cream cheese brands have been performing well, she said.
Buffett's Berkshire Hathaway held nearly 193,000 Kraft shares as of the firm's most recent SEC filing.
Asked whether Buffett is making a mistake by getting involved in a processed food company at a time when Americans are shifting to smaller, more nutritional brands, Howard noted that 3G's cost-saving structure has allowed Heinz to become more profitable, despite the fact that it's frozen foods business is shrinking.
"From a profit perspective and a shareholder value perspective, it makes a lot of sense, but in terms of the long-term growth algorithm on the top line of the industry, I think they are coming down," she said.
—CNBC's Gina Francolla and Reuters contributed to this story.