Heineken may struggle to cope with the size of its new UK portfolio following its joint takeover of Scottish & Newcastle, say industry experts.

The Dutch brewer will take control of S&N's UK portfolio along with its Portuguese, Finnish, Belgian, US and Indian operations. Partner Carlsberg will take control of the Russian, French, Greek, Chinese and Vietnamese businesses.

"It will be interesting to see how Heineken will retain the expertise of S&N in terms of category management," said Dan Jago, Tesco category director, beers, wines & spirits. "Scottish & Newcastle is an outstanding supplier and has plenty of expertise in dealing with several brands. Heineken does not have that experience and it is a concern."

The challenges facing Heineken have prompted speculation that the brewer will sell off some of the S&N brands it inherits.

"Heineken will clearly be taking a long hard look at its options and this may mean some of the S&N brands will be sold off," said Charles Stanley analyst Sam Hart, adding: "It will be interesting to see what it does with cider."

The Campaign for Real Ale (CAMRA) has raised concerns over the future of S&N's real ale brands. "The inevitable result of consolidation is brand losses, brewery closures and less choice for consumers," said chief executive Mike Banner.

Combining brand portfolios would be the biggest challenge facing the newly merged companies, said management consultants the Hay Group.

"Carlsberg and Heineken are effectively buying a brand-holding company in S&N," said Hay Group M&A specialist David Derain. "Combining these companies will be a case of integrating several different brand cultures. These sorts of deals are always more difficult."

The deal, which valued S&N at £7.8bn, is expected to be completed in the second quarter of this year.