FrieslandCampina Hungária, the Dutch cooperative's Hungarian business, sealed a deal late last week with Székesfehérvár-based Alföldi Tej to sell the plant for an undisclosed sum.
Production will continue at the plant "without interruption," said FrieslandCampina.
Under a toll manufacturing agreement between the parties, dairy products produced by Alföldi Tej at the plant will be marketed by FrieslandCampina.
Alföldi Tej will assume control of the plant in the next few weeks following the completion of "some necessary procedures," said FrieslandCampina.
No job cuts are expected at the plant, it added.
"This agreement is very much in line with the company's objective to maintain the jobs of the employees of the Debrecen plant and to safeguard the future of the dairy industry in Debrecen," said Peter Szautner, managing director, FrieslandCampina Hungária.
"With this step, FrieslandCampina's process and logistic realignment has been completed."
"We believe that we have reached a positive and sustainable outcome. With this deal, the company is showing its continuous commitment to the local market, production in Hungary and the most complete service available to satisfy consumer needs," Szautner added.
The "realignment" of FrieslandCampina Hungária's processing and logistics operations, devised to maintain FrieslandCampina's "strong presence" in the country, began in December 2012 when it announced plans to close its plant in Debrecen by September 2013 unless a buyer was found.
It also revealed plans for an expansion of its plant in Mátészalka and initiated a project to restructure its logistics operations.
New lines, for the production of Mia brand desserts and Milli cream products, were unveiled at its Mátészalka plant in July 2014.