UPDATE 2-Mill Road Capital to buy Rubio's for $91 mln

* Offer at $8.70/shr

* Offer represents 14 pct premium to Rubio’s Friday close

* Rubio’s reports higher quarterly results (Adds details, background, share movement)

May 10 (Reuters) - Mexican restaurant chain Rubio's Restaurants Inc RUBO.O said it agreed to be acquired by private equity firm Mill Road Capital LP for about $91 million in cash.

The offer of $8.70 a share represents a premium of about 14 percent to Rubio’s Friday closing price of $7.66.

Private equity firms lately have been showing renewed interest in restaurant companies, with the start of a consumer spending recovery and greater access to capital.

CKE Restaurants Inc CKR.N, the owner of Hardee's and Carl's Jr fast-food chains, agreed to be bought by Apollo Management in April, and a source told Reuters in March that RDG Capital has bid for Japanese-style restaurant chain Benihana Inc BNHN.O.

The latest offer for Rubio’s comes seven months after the company rejected an unsolicited buyout offer of $8 a share -- a 33 percent premium to its then stock price -- from an investor group consisting of Alex Meruelo and his affiliates and Levine Leichtman Capital Partners IV LP. [ID:nBNG385436] [ID:nBNG499111]

Meruelo, a California-based real estate developer and founder of the La Pizza Loca chain, controls 11.6 percent of Rubio’s outstanding shares, according to a filing with the U.S. Securities and Exchange Commission in April.

Rubio’s said its founder and Chairman Ralph Rubio, Chief Executive Daniel Pittard and private equity firm Rosewood Capital collectively own about 24 percent of the company’s outstanding shares, and have committed to vote in favor of the proposed deal with Mill Road Capital.

Greenwich, Connecticut-based Mill Road Capital owns about 5 percent of Rubio’s outstanding shares, the company said in a regulatory filing.

The transaction has been unanimously approved by Rubio’s board and the deal is expected to close during the third quarter, the company said.

Rubio’s -- which operates more than 195 restaurants in California, Arizona, Colorado, Utah and Nevada -- also reported a first-quarter profit of $367,000, or 4 cents a share, up from $245,000, or 2 cents a share, a year earlier.

Excluding items, it earned 5 cents a share.

Revenue rose 1 percent to $46.7 million for the quarter.

Restaurant operating margin rose to 16.6 percent, from 15.7 percent a year earlier.

Rubio’s shares rose 12 percent to touch a two-year high of $8.60 in morning trade Monday on Nasdaq. (Reporting by Renju Jose in Bangalore; Editing by Anne Pallivathuckal and Don Sebastian)