This new deal with China is expected to add £200 million (m) to the domestic food industry and, for the first time, will see trotters exported from UK.
The new agreements include approval to export from five sites in Suffolk, Lincolnshire, Derbyshire, Co Antrim and Co Tyrone. The four businesses in Northern Ireland are Karro Foods, Cranswick County Foods, Interfrigo and Granville Food Care. In England, the businesses given approval are Cranswick Country Foods in Hull and two unnamed cold stores.
All of the plants were inspected by China's Certification and Accreditation Administration (CNCA) technical experts in April 2015, with a separate team of inspectors from the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China (AQSIQ) also visiting Northern Ireland in April 2015 to audit pork fifth-quarter production standards for export.
According to Northern Ireland's Department of Agriculture, Environment and Rural Affairs (DAERA), shipping will not start for another two to four weeks while the administration is organised on both sides, but producers are able to start packing products with a view to exporting.
Nine UK producers already export pork to China, generating £43m last year, while demand for UK pork has doubled in terms of value over the past three years.
Department for Environment, Food & Rural Affairs (Defra) minister of state George Eustice said: "China is a hugely important market for our world-class food industry and, by opening up access even further, more UK businesses can take advantage of the growing appetite for our food and drink.
"British food is produced to the very best standards of welfare, quality and safety and this growth in exports to China is creating more jobs and opportunities for our premium pork producers, who can guarantee quality from farm to fork."
Northern Ireland's chief veterinary officer Robert Huey said the access could be worth £10m to Northern Ireland alone. "This is very welcome news for the Northern Ireland pig sector and for our wider agri-food industry and I look forward to the commencement of exports to China. The deal represents a major boost worth in excess of £10m for the local pork industry.
"This welcome news follows concerted efforts by Defra, supported by the government and industry in Northern Ireland. By recommending approval, the Chinese authorities have recognised the rigorous standards Northern Ireland has in place to produce our high-quality, safe and wholesome pork. We place a clear emphasis on traceability at the heart of our production and processing and recognise that a joined-up, safe and efficient food supply is essential."
Northern Ireland Office Minister Chloe Smith MP said: "I welcome the news that seven UK businesses, including companies based in Northern Ireland, have secured market access for the export of pork to China. It is an exciting example of what the Northern Ireland agri-food sector and, indeed, export market can be, and of what we can achieve in terms of trade, jobs and new opportunities as we build an economy that works for everyone."
Dr Phil Hadley, international market development director for the Agriculture & Horticulture Development Board (AHDB), said: "We are absolutely delighted this new deal has been agreed with China, which will support jobs and create opportunities for UK pork producers for years to come.
"This agreement with China comes hot on the heels of this week's announcement that a £34m deal has been agreed to export UK beef to the Philippines. It is great to hear so much positive news around exports of UK meat and is a testament to the hard work being done to promote the UK food industry on a global stage."
The National Pig Association added that it was "exceptionally happy with this development".
In a statement, it said: "Many people have worked on this deal and we would like to thank all those through the years throughout industry and in government who were involved in securing this amazing result."