Analysts say the proposed $17 billion takeover of RJR Nabisco Inc. by its top executives amounts to "a gift" at $75 a share and that there's no predicting what will happen in the rapidly consolidating industry of edibles that has seen a flurry of hostile takeover attempts this week.

With backing from one of the nation's largest financial institutions, RJR Nabisco Inc. managers said Thursday they are pondering buying out the company, makers of Oreo cookies and Camel cigarettes, in what would be the largest corporate acquisition in U.S. history.Also Thursday, Kraft Inc., makers of processed cheeses and other foods, announced it would not melt under pressure to enter negotiations with tobacco industry giant Philip Morris Cos., which has cast its corporate eye on taking command at Kraft.

Earlier in the week, Pillsbury's board of directors rejected an unsolicited bid for the doughboy dynasty by Britain's Grand Metropolitan, a restaurant and liquor conglomerate.

Nabisco managers have summoned Shearson Lehman Hutton Inc. to help in the dollar dealing department of their proposal, which was initiated by F. Ross Johnson, Nabisco's chief executive and Edward A. Horrigan Jr., chief executive officer of its tobacco division and other managers.

"Shearson can confirm that it has been working with the management group on a possible management-led buyout," said Michael O'Neal, a spokesman for Shearson Lehman Hutton.

Shearson Lehman would provide "the equity and the mezzanine financing," O'Neal said.

"It would arrange the senior bank financing and act as the financial adviser to the management group in a possible financial transaction," he said.

Financial analyst Clinton Mayer of Bear Stearns & Co. in New York called the $75-a-share offer "a gift because it is a substantial premium over previous market value."

"This stock should be worth a minimum of $85," Mayer said. "The current market value is $76, so that's only a dollar above the bid price."

Mayer said if the leveraged buyout of RJR Nabisco goes through "it obviously means there will be one fewer company to attract a possible suitor. With fewer major players, it's possible that the whole process of these acquisitions may peak . . . but there is no predicting what will happen."

RJR Nabisco's stock soared by $19.50 to $75.375 after the announcement in hectic trading on the New York Stock Exchange, where it was the most active issue.

RJR Nabisco also reported Thursday record third quarter net income per common share of $1.55, up 25 percent from $1.24 per share in 1987. The company's net income was $355 million, up 11 percent from $320 million in the third quarter of 1987.

"Any proposal, if made, would be reviewed by a special committee composed of outside directors, which has been established by the board," the statement said.

Charles E. Hugel, chairman of RJR Nabisco's board and head of the special committee, said no determination has been made regarding the acceptability of any such proposal.

Hugel said the board has not determined whether to recommend the sale of RJR Nabisco and may not accept any such proposal.

In a leveraged buyout, some or all of the assets of the target company are often sold to finance the transaction.

In 1987, RJR Nabisco, the 19th-largest industrial company in the United States, had 1987 sales of $15.87 billion.

Among the company's well-known brand names are Camel and Winston cigarettes, Nabisco cookies, crackers and snack products and Del Monte canned fruits and vegetables.

The development came on the heels of Philip Morris's $11.8 billion bid for Kraft, based in Glenview, Ill., after the stock market closed Monday.

If the RJR Nabisco deal were to go forward, and if it were to be completed, it would be the largest corporate takeover in U.S. history, surpassing the $13.3 billion purchase of Gulf Oil Corp. by the Chevron Corp. in 1984.

With 120,000 employees, RJR Nabisco is the third-largest maker of consumer goods in the United States, after Philip Morris Co. and Proctor & Gamble.

Last fall, the company transferred its corporate headquarters to Atlanta from Winston-Salem, N.C.