At least one analyst thinks these popular cereals from General Mills might be on the M&A menu of private equity, which has caused speculation Warren Buffett might be wanting a bowl for himself.

If analyst speculation is true that Brazilian hedge fund 3G Capital may be interested in using its position in Kraft Heinz (NASDAQ:KHC) to engineer a merger with cereal maker General Mills (NYSE:GIS), it could be a sign that Warren Buffett hasn't satiateds his appetite for big consumer brands.

A report from Citigroup analyst David Driscoll that the private equity firm had its eye on the owner of Cheerios, Lucky Charms, and Betty Crocker caused a flurry of speculation about how it could achieve its goals. A story on Bloomberg suggested 3G could hike operating margins at the cereal maker as high as 25%, a near-8-percentage-point increase over their current 17% level, by initiating some of the same tough cost-cutting policies it's implemented since merging Kraft and Heinz.

It was, of course, Warren Buffett who assisted the hedge fund in first taking Heinz private and then helping it engineer the merger of the two packaged goods companies. The billionaire investor has been closely involved in many of the machinations that have gone on with Kraft, where he had been the largest shareholder.

Back in 2010 he was annoyed Kraft was buying the candy business of chocolates maker Cadbury, and ended up selling down his stake in a pique. And then when Kraft spun off Mondelez International (NASDAQ:MDLZ) over his objections, he sold off its shares once more. So it may have been a bit of fitting retribution for Buffett when he teamed up Berkshire Hathaway (NYSE:BRK-A)(NYSE:BRK-B) with 3G Capital to invest $10 billion to have Heinz take over Kraft.

Kraft Heinz could be the vehicle that's used to acquire more big-name brands to expand their reach globally.

But a possible merger with General Mills does seem a bit outside of the direction analysts thought 3G Capital was heading when it brought the two packaged foods giants together. It was thought the union had more global ambitions in mind, because Heinz had an international platform that could take Kraft's domestic operations global. A quarter of General Mills' revenue, however, comes from international markets.

It also seemingly goes against Buffett's own belief that Kraft Heinz had its hands full just completing its own merger. While he is fond of buying powerhouse brands, and General Mills owns more than a few, late last year it was reported hedge fund operator Bill Ackman had made a big $5.5 billion bet on Mondelez believing it would be a takeover target, and that Kraft Heinz would be a potential buyer. But Buffett shot down the notion saying, "Frankly, most of the food companies sell at prices that it would be very hard for us to make a deal even if we had done all the work needed at Kraft Heinz."

At the time, Mondelez's enterprise value was trading at around 17 times adjusted EBITDA and was at new 52-week highs. It also had some $19 billion worth of debt. General Mills, on the other hand, currently trades at an EV/EBITDA of 13.4, but has some $7 billion in long-term debt, has less than $800 million in cash, and is trading at record highs.

Buffett has been chastised in the past by some shareholders for teaming up with 3G Capital because of its notorious adherence to cutting expenses, though the billionaire investor has defended its work, saying it was just right-sizing businesses and he hoped Berkshire Hathaway businesses were right-sized as well.

General Mills has found itself on both sides of the mergers and acquisitions equation, and was even considered a potential suitor of Mondelez precisely because of a possible Kraft Heinz acquisition attempt. While the packaged goods giant may get a voracious appetite for making deals again, if Warren Buffett's own words are to be believed, it's hard to think he will be helping the Brazilian hedge fund make this particular bid anytime soon.