Tortilla giant gets new lease on life

The world's largest tortilla-maker has largely succeeded in its seven-year quest to earn redemption from credit-ratings companies. To bondholders, though, the company still isn't getting its due.

While Gruma SAB regained its investment grade from Standard & Poor's on March 27, its benchmark borrowing costs show the rating should be even higher.

Its $400 million of notes due 2024 yield 0.85 percentage point less than the average for emerging-market firms that share the company's BBB-grade.