OMAHA, Neb. — Billionaire Warren Buffett likes to compare his company to a masterpiece that he’s been painting for nearly five decades, and the deal he announced Tuesday will permanently alter the color of Berkshire Hathaway’s portrait.

The 79-year-old investor plans to add a brilliant orange section to the painting, as in the brightly colored locomotives of Burlington Northern Santa Fe Corp. that Berkshire will acquire in a $34 billion cash and stock deal — the biggest deal yet in a career of big deals.

Buffett described it as an “all-in wager on the economic future of the United States,” but it’s also transformative for his company. The BNSF deal will make freight railroads Berkshire’s third-largest industry after insurance and utilities.

“I think it’s classic Buffett,” said Andy Kilpatrick, the stockbroker-author who wrote “Of Permanent Value: The Story of Warren Buffett.”

Throughout the nation’s economic struggles of the past two years, Buffett and Omaha-based Berkshire have been busy making deals, but few of those were outright acquisitions.

Berkshire’s recent big deals include investing $6.5 billion in equities related to Mars Inc.’s acquisition of Wm. Wrigley Jr. Co., $5 billion in preferred shares of Goldman Sachs Group, $3 billion in General Electric Co. and $2.6 billion in Swiss Reinsurance Co.

Those financing deals have given Berkshire substantial stakes of at least 10 percent and, in some cases, warrants to buy stock. As a result, the company has collected millions in interest.

Last year, Berkshire failed in its attempt to buy Constellation Energy Group. But even failure was profitable because of the deal’s breakup terms.

MidAmerican Energy Holdings, Berkshire’s utility division, received 20 million Constellation shares and $593 million in cash last year after Baltimore-based Constellation rejected MidAmerican’s $4.7 billion takeover bid in favor of a deal with Electricite de France SA. MidAmerican has since sold the Constellation stock.

Buffett hasn’t gone through the recession mistake-free. Earlier this year, he acknowledged he shouldn’t have bought 79.9 million shares of ConocoPhillips stock when oil and gas prices were near their peak.

But Berkshire has partly made up for that misstep by selling some of the ConocoPhillips stock to generate a loss to offset past capital gains taxes.

Berkshire’s biggest acquisition before BNSF was the $16 billion stock purchase of reinsurance giant General Re, announced in 1998.