Chinese authorities announced on Thursday that more than 900 people had been detained over the past three months for "meat-related offences". One alleged gang is suspected of using illegal chemicals to transform rat, mink and fox meat into counterfeit mutton slices – popular for their use in hot pot – and selling them to local markets. Responding to the scandal, police in Zhejiang province posted a guide to distinguishing between real and fake mutton on China's most popular microblogging site, Sina Weibo. Here is a translation of their instructions.

Real v fake mutton

Real mutton, left, and fake mutton in a picture taken from Chinese public safety blog

Today I'm going to share with you how to distinguish between real and fake mutton. If you don't look carefully, it's very hard to tell the difference – both have streaks of red and white meat. But after a bit of careful observation, we can tell that there's really a big difference.

For fake mutton, the streaks of white and red meat are separate. The white is white, and the red is red. The white and red streaks in real mutton are interlocking. The streaks are very distinct, and look very natural.

The best way to tell whether the mutton is fake is to thaw out the slices. After they've been thawed, fake mutton slices immediately revert back to their original shape. Lets look at the following pictures. After the fake mutton is thawed, the red and white streaks come apart at the slightest touch.

The thawed meat on the left separates more easily, suggesting it is not mutton

Lets look again at the real mutton slices. Another thing that's different about real mutton – when we tear the slices by hand, the white and red meat stick together. The quality of the meat is very natural.

Look at the real and fake meat slices after they've been completely thawed. It's obvious – with fake mutton, the red and white parts are completely separate. And they look like they were pieced together. The streaks on the real mutton slices are also very obvious. They look very natural.

Real and fake mutton after boiling

Put the fake mutton into the hot pot to boil for a bit and take a look. This here has been boiled for about two minutes. After hitting the boiling water, the fake kind began to fall apart, and the colour became unnatural. For real mutton, the meat tightens up.

Now do you know how to tell the difference between real and fake mutton?