Union leaders are seeking a jobs guarantee after the UK's biggest brewer accepted a £7.8bn takeover offer from European rivals Carlsberg and Heineken.
The deal will herald the break-up of Edinburgh-based Scottish & Newcastle, whose UK operation and 3,300 staff will pass to Dutch giant Heineken.
Edinburgh business leaders are also seeking reassurance for staff at the company's headquarters in the city.
Iain MacLean, of the Unite union, said he was "concerned" about UK jobs.
He said: "It will result in a period of uncertainty for the workforce and we are primarily concerned about the implications for UK jobs.
"We have a meeting with Scottish & Newcastle next week and we will be looking for Carlsberg and Heineken to guarantee the security of our members' jobs."
Ron Hewitt, Edinburgh Chamber of Commerce chief executive, said the takeover news was both happy and sad.
"Sad because in a way it is the end of a brewing tradition which goes back hundreds of years," he said.
"The reality is, however, that it is great news because it is a vote of confidence in yet another Edinburgh-based business.
"Our only concern is to ensure this major headquarters in Corstorphine Road remains in Edinburgh."
He said the Edinburgh headquarters had administrative staff at the "highest skill level".
Heineken would not comment on potential UK job losses. The Dutch firm currently has no brewing operations in the country.
The deal also raised concerns from the Campaign for Real Ale (Camra) over consumer choice and the future of S&N's real ales, such as John Smith's.
Camra chief executive Mike Benner warned: "The inevitable result of consolidation is brewery closures, brand losses and less choice for Britain's consumers."