The committee, which is chaired by Debbie Stabenow, is examining how take-over will affect food security in the US and also the long-term implications on the economy of acquisitions of US companies by foreign companies, in particular from China.

Sen Stabenow said: “We need to be having this conversation and evaluating what is in the best interests of American families and our American economy because of the importance of our food supply, security, and safety.”

She added: “We need to be evaluating the long-term market implications of this deal for American workers, pork producers, and the farmers who grow grain and feed ingredients.

“Despite the strength of America’s pork sector, Smithfield has been struggling to make a profit -- and yet Shuanghui is offering to pay a 30 per cent premium for the company.

“That, to me, raises questions about the economic motivations of the purchase.”

However, since the deal was announced it has received broad-based support from local, state and national elected officials, industry labour unions, US pig farmers, leading economic and international affairs academics and even US based food industry peers.

Smithfield Foods’ president and chief executive officer, C. Larry Pope, in his testimony explained the combined company's commitment to continuing to work with American producers and suppliers that have played an integral role in Smithfield's success.

"With respect to agriculture, we expect this transaction to drive growth and expansion not only for our growers, but for the entire U.S. pork industry. Smithfield Foods owns over 400 hog farms and has contracts with more than 2,000 family farmers across the country. Our agreement with Shuanghui will maintain all of these contracts and arrangements. Moreover, this transaction creates a terrific opportunity through growth in exports for U.S. hog farmers to expand production to meet the growing Chinese demand,” he said.

"The integrity of our brands, our record of safety, the safety of the US food supply chain and the recognized effectiveness of US food safety standards are key drivers of the value that Shuanghui places on Smithfield.

“Our brands are recognized as representing highest-quality, safe and sought-after products throughout the world, including in China. Our combined company thus has every incentive to ensure the continued safety and excellence of our products and brands.

“Smithfield's facilities will continue to maintain their quality and will experience the same rigorous level of USDA FSIS inspection, regardless of the ownership of this company. Absolutely nothing about how our products are made, inspected or distributed will change."

Mr Pope added: “Shuanghui intends to retain Smithfield's management team, its plants and its employees. Shuanghui recognizes Smithfield's best-in-class operations, outstanding food safety practices and 46,000 hard-working employees.

“There should be no noticeable impact on how we do business operationally in America and around the world as a result of this transaction, except that we will do more of it."

Dr Usha Haley, Professor and Director at the Robbins Center for Global Business and Strategy, West Virginia University fired a warning shot in her testimony to the committee.

“If completed, this deal, the largest takeover of a US company by a Chinese company, will double the number of US jobs tied to direct investment by China,” Dr Haley said.

“After the acquisition, Smithfield will cease to be publicly traded and information on operations will come through Chinese reports.

“The magnitude of this deal in a strategically important global industry will almost certainly affect food safety, how we do business in the United States, US companies’ and regulatory agencies’ modes of participation, US competitive environments (including company evaluations, pricing mechanisms and other food producers' competitive positions), efficiencies, intellectual property (IP) protection, and compatibility with US industrial, economic and cultural policies. There is little doubt that this Chinese foray will be the first of many in the U.S. food and agricultural sectors.

“Consequently, the deal merits a thorough examination by the Committee on Foreign Investment in the United States (CFIUS) and broader participation by the Department of Agriculture and other affected parties.”

She added: “Shuanghui has not released its profitability figures, but most of the companies we studied would have been bankrupt without subsidies.

“US companies would be unable to compete domestically and in exports against a Shuanghui-Smithfield that does not pursue profits but is heavily subsidised and aims for industry domination.

“US competitors would be forced to reduce their profit margins to compete, and in this consolidated industry, cost-cutting and bankruptcies would ensue in a very short time, perhaps in as little as two or three years (as with the solar industry).”

Daniel Slane, Commissioner for the US-China Economic and Security Review Commission at the US Chamber of Commerce said that a central issue in the deal is China’s rising outbound investments.

“Beijing has issued a directive to their state-owned and state-controlled entities to ‘Go Abroad’.

“I recognise that, as China’s economy matures, its companies will seek to acquire assets and enter new markets overseas, a process that can aid China’s transition to a new growth model,” he said

“I remain concerned about how China is making these investments.

“Many of the largest Chinese enterprises, including Shuanghui, maintain strategic ties to the Chinese Government, whether through direct ownership or control, preferential access to massive government subsidies, and personal links to the Chinese Communist Party.

“These companies are also tapping into the huge foreign exchange reserves that the central bank has accumulated through currency manipulation and capital controls.

“I am also concerned that China’s outbound investment is part of a concerted effort to acquire strategic assets, either downstream in intellectual property and brands, or upstream in natural resources.

“In my view, the purchase of Smithfield by China is the first of what I expect will be many forays into rural America.

“I think it is reasonable for you to expect a wave of Chinese investments into our food and agriculture industry and this potential purchase is not a one off. Today it’s Smithfield, but tomorrow it could be Consolidated Grain, ConAgra or Tyson Foods.”

Matthew J. Slaughter, Associate Dean for Faculty, Signal Companies' Professor of Management and Faculty Director of the Center for Global Business and Government at Tuck School of Business, Dartmouth College said that merger-and-acquisition transactions have long been the main strategy the long-standing strategy by which global companies establish and expand operations in America.

He added: “The U.S. affiliates of global companies - despite accounting for far less than one per cent of US businesses - have long performed large shares of America’s productivity-enhancing activities that lead to high average compensation for millions of American workers.

“All public information about the Shuanghui-Smithfield transaction indicates it will benefit Smithfield stakeholders -including, importantly, its employees - and the broader US economy.

“There is nothing inherently worrisome or unusual about the Chinese and food aspects of this transaction.

“Chinese purchases of American companies will help strengthen both China’s own development efforts and its commitment to market- and rules-based engagement with the global economy.

“The United States already has substantial inward FDI in agriculture and food processing. “