NEW YORK — Billionaire Warren Buffett is dipping into the ketchup business as part of a $23.3 billion deal to buy H.J. Heinz Co., uniting a legend of American investing with a mainstay on grocery store shelves.
It’s the largest deal to date in the food industry and is intended to help Heinz accelerate its transformation into a global business. The company, based in Pittsburgh, also makes Classico pasta sauces, Ore-Ida potatoes, and Smart Ones frozen meals.
Buffett’s Berkshire Hathaway and its partner on the deal — 3G Capital, the investment firm that bought Burger King in 2010 — say Heinz will remain based in Pittsburgh.
Heinz chief executive William Johnson said at a news conference that taking the company private would give Heinz the flexibility to make decisions more quickly, without the burden of having to report quarterly earnings.
Heinz was founded by Henry John Heinz and his neighbor L. Clarence Noble in 1869. The first product was grated horseradish, bottled in a clear glass to showcase its purity. Ketchup was introduced in 1876.
Secretary of State John F. Kerry and his wife, Teresa Heinz Kerry, could make up to $1 million from the sale, according to financial data.
Heinz Kerry, the heir to the Heinz family fortune through her late husband Senator John Heinz of Pennsylvania, held at least $3 million worth of stock as of 2010, according to Kerry’s most recently available financial disclosure statements.
It is unclear if she has sold any of those holdings. But Heinz shareholders will receive $72.50 in cash for each share of common stock. The transaction value includes assumption of the company’s debt.
Last year, Heinz had revenue of $11.6 billion, with ketchup and sauces accounting for just under half of that. Given the saturated North American market, it has increasingly been looking overseas for growth. In 2010, for example, the company bought Foodstar, which makes Master brand soy sauce and fermented bean curd in China. Heinz expects emerging markets to account for a quarter of its sales this year.
The deal spares Kerry any headaches that might arise from a possible conflict of interest involving the company. Before taking the post earlier this month, Kerry agreed to remove himself from certain decisions that might affect the company and its 16 international subsidiaries.
The sale will have little impact on the Heinz Endowments, the $1.4 billion philanthropy Heinz Kerry chairs. A spokesman said Thursday that Heinz company stock only makes up 1.2 percent of the foundation’s investments.
Johnson said the deal got under way eight weeks ago when managing partners from 3G Capital visited him for lunch. The men were familiar with each other because Heinz is a supplier for Burger King.
‘‘We did not solicit this,’’ Johnson noted.
Buffett said on CNBC that 3G’s billionaire cofounder Jorge Lemann approached him about the Heinz deal on a plane they were on in early December.
Although 3G Capital has a record of aggressively cutting costs at businesses it acquires, managing partner Alex Behring noted at the press conference that Heinz is different because the business is healthy and has been growing its core sales.
Buffett has said he’s been hunting for elephant-sized deals. He said on CNBC Berkshire had about $47 billion in cash at the end of 2012.
Heinz’s brands have power with shoppers that takes years to create, and it has been able to raise prices even in the highly competitive grocery business, said Brian Sozzi, chief equities analyst for NBG Productions.
‘‘There isn’t going to be another Heinz brand,’’ he said. ‘‘It has a durable competitive advantage.’’
The deal is a departure for Buffett’s firm, Berkshire Hathaway. Generally, Buffett prefers to buy entire companies.
The per-share price for the deal represents a 20 percent premium to Heinz’s closing price of $60.48 on Wednesday.
Bryan Bender of the Globe staff contributed to this report.