Twinkies are back ... and now they'll last a lot longer

Although many consumers may be under the false impression that Twinkies last forever, they do in fact have a shelf life and that's about to increase.

As the famous spongy yellow cakes are reintroduced to stores this week, they will last for nearly twice as long as they did originally. Now, the snacks will last for 45 days before they must be replaced on shelves, up from a 26 days previously.

In an interview Monday with "Squawk on the Street", C. Dean Metropoulos, CEO of C. Dean Metropoulos & Co., the private equity firm that partnered with Apollo Global Management to purchase Hostess out of bankruptcy, shed some light on the change.

(Related: Want your Twinkies rush earlier? Head to Wal-Mart)

Metropoulos said changes that increased the longevity of Twinkies were already in the works before the company was purchased.

"It's a matter of balancing ingredients," he said, explaining that a number of Ph.D.s have been working on the innovations for Twinkies. "There has been very little change in the ingredients, if anything an upgrade. It's more about the balance of the ingredients, the cooking temperatures, the moisture levels, etc."

(Related: Have Twinkies killed the union movement?)

The company has also said that it will deliver frozen Twinkies to retailers upon request, in order to further extend shelf life.

"It's been minor changes, not dramatic ones," he added. "We're focused on the Twinkie and we're happy it's back."

—By CNBC's Paul Toscano. Follow him on Twitter and get the latest stories from "Squawk on the Street" @ToscanoPaul.