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 US food supplier OSI Group, which came under fire in China last year over allegations it used out-of-date meat, has criticized the handling of the case by the local food regulator, a rare act in China where firms are usually careful not to openly challenge the authorities.
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OSI's Shanghai Husi Food plant came under the spotlight in July when an undercover Chinese media report showed workers using expired meat and doctoring production dates.
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The firm, which supplied international fast food chains including McDonald's and Yum Brands, launched a sweeping recall last summer that culminated on Sunday when it said it had destroyed the products.
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The Shanghai Food and Drug Administration, which is still investigating Shanghai Husi over the matter, called the food that was destroyed on Sunday "questionable" in a routine statement, prompting the strong objections from OSI.
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The statement said Chinese rules defined "questionable" food products as those which did not meet food safety standards or could be harmful to human health.
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OSI's criticism escalated a rare war of words between a foreign company and Chinese regulators, who over the past year have closely scrutinized international firms in industries ranging from automobiles to high-tech.
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Microsoft, for instance, has expressed deference to Chinese anti-monopoly regulators looking into its software sales practices£Âeven while US business lobbies have complained about their companies being unfairly targeted.
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OSI's tussle with its Shanghai regulator also comes at a time when the central government in Beijing has acknowledged China's struggles to regulate tainted products.
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China's top food watchdog said on Wednesday that food and drug safety in the country was "grim" and pledged stronger oversight in the wake of a string of food scandals which have hit the reputations of brands including McDonald's, Yum and retailers Carrefour and Wal-Mart Stores.
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The Shanghai Husi scandal, which spread as far as Hong Kong and Japan, sparked a Chinese probe into the firm and dragged down Chinese sales at KFC-parent Yum and McDonald's. Both have since cut or suspended ties with OSI, which has its headquarters in Aurora, Illinois.