Whitehall sources pointed to institutions like the BBC, the DVLA, the Passport Agency, the UK Border Agency, Ofcom, the Pensions Regulator, UK Financial Investments, the Civil Aviation Authority and the Met Office as examples.
Yet the first of a series of such papers published by the UK Government was branded an "own goal" after one of the authors of the legal opinion, Professor James Crawford of Cambridge University, said the SNP Government's 18-month transition for independence – dismissed as fanciful by Coalition sources – was "realistic".
He also said the application for membership of international bodies by a newly independent Scottish state would not be difficult in most cases.
Nicola Sturgeon, the Deputy First Minister, said: "The fact the UK Government's own legal experts have backed the Scottish Government's negotiation timetable and accepted that EU negotiations need not be difficult is a huge own goal and betrays the entirely 'can't do' attitude of the No campaign."
The paper says if a new Scottish state wanted to continue with the same functions as presently provided to Scots by the UK Government, it would need to "establish new institutions or significantly expand capacity in existing ones" and there would inevitably be transitional costs.
The report notes: "To give an indication of the scale, around 490,000 staff are employed in over 230 UK central government organisations. More than 140 of these organisations perform functions for Scotland, reserved to the UK Government."
This number includes Government departments like the Foreign Office, bodies which oversee UK-wide activities such as energy and railway regulation as well as a raft of other public bodies and agencies.
It states: "To perform the same functions that are provided by the UK, the Government of an independent Scottish state may need to create up to four times as many Scottish public organisations as currently exist."
At present, some 27,000 civil service staff are employed in some 50 Scottish Government organisations.
The Herald was told UK organisations were just that and, if Scots voted for independence in next year's referendum, a new Scottish state would have to start from scratch.
The opinion by Mr Crawford argued an independent Scotland, for the purposes of international law, would be a new state while the UK would be the continuing state. This would mean an independent Scotland would have to agree thousands of new treaties and apply to join a raft of international organisations like the EU, UN and Nato.
Michael Moore, the Scottish Secretary, launching the paper in Edinburgh, said the idea such negotiations would be a piece of cake was wrong.
He said: "It would be a process that would require two sets of constructive but hard-headed negotiators, and then a parallel set with 27 in one case (the EU) and many others in other international organisations."
The Secretary of State also said that, while an independent Scotland would not inherit the UK's existing rights under such treaties, it would inherit a share of the UK national debt. He said: "We would need an equitable distribution of the liabilities."
In response, Ms Sturgeon branded the Coalition's position hugely arrogant, which betrayed a "near colonial attitude".
She said: "A legal opinion is just that. There are opinions from other legal experts that say the opposite – that Scotland would be a co-equal successor state. These matters would be settled by negotiations."
Anas Sarwar, for Labour, welcomed the paper as marking a "new phase in the debate about Scotland's future as we move from assertion and spin to evidence and fact" and said it highlighted the "strong ties that bind Scotland to the UK".
Ruth Davidson, the Scottish Tory leader, said the report "shatters the myth pedalled by Alex Salmond that independence would be a smooth process without any major upheaval". She added: "The onus is now on the SNP and others wanting to take Scotland out of the UK to set out the evidence and facts to support their position."
* A man has bet £4400 Scotland will become independent by January 1, 2020. The stake has been placed at a branch of William Hill in London. The mystery gambler, who is thought to be Scottish, stands to win £30,800 at odds of 7/1 if separation from the UK goes ahead.