China has found itself embroiled in another food safety scandal after authorities discovered 100,000 tons of smuggled frozen meat - some of which was over 40 years old and had begun to thaw - apparently destined for sale and consumption.

"I nearly threw up when I opened the door," an inspector said of the aging meat's overwhelming stench.

Chinese authorities found the smuggled pork, beef and chicken wings in 14 different crackdowns across the country. The haul is reportedly worth in the region of 3 billion yuan ($480 million), reported the Beijing News.

Industry sources say hundreds of thousands of tons of beef is being smuggled into China via Hong Kong and Vietnam. Some of the seized meat came from strategic food reserves from countries such as Brazil, India, Finland, Germany and the US.

"This old meat is extremely cheap. Because it is smuggled into China, there is no food quality inspection. In order to avoid food safety inspections, the smugglers will avoid big cities such as Beijing and Shanghai, and smuggle it into small restaurants in small and medium cities in Yunnan, Guizhou and Sichuan provinces," said an insider.

Recent news reports said that mostly fresh meat is sold in supermarkets in Beijing. Many meat providers said they only provide fresh meat.

An official at China's anti-smuggling bureau told the paper that smuggled meat can travel for extended periods of time in unrefrigerated vans and is often repeatedly thawed and refrozen, making it a breeding ground for dangerous bacteria and viruses.

Insiders said that even with the crackdown by authorities the high profits involved means there will always be criminals willing to engage in this illegal trade.

Organized gangs even offer a "one-stop shop" service for buyers which includes finding suppliers, organizing transportation, customs clearance and delivery.

Payment is often in cash or done online which makes investigations into their illegal activities even harder.

The smugglers use various social media platforms to communicate and are very cautious.

A food safety official said, "Frozen food smugglers have a network that covers the entire country, so any crackdown needs to be a multi-province effort, especially in the main battlefields of Hunan, Guangdong, Guangxi and Yunnan."