Milk has played an important role in the development of agriculture and animal husbandry in Europe and Asia. A griddle found in Poland suggests that cheese was made in as early as 6,000 BC. But it was never known how cheese was made at that time because of the lack of fossil evidence.

"We not only identified the product as the earliest known cheese, but we also have direct ... evidence of ancient technology," study author Andrej Shevchenko told USA Today, saying the technique is easy and cheap and works for the common people.

The age of the cheese was identified with the samples discovered in the same tomb, such as seeds and textiles. The cheese was preserved because of the extreme dryness in the desert. The lack of water restrains the growth of microbes, which could biodegrade organic substances, Yang says.

Archaeologists believe it to be either sacrifices or food for the woman in her afterlife. No book has recorded the exact use of cheese in the tomb, Yang says.

"But it does show that milk production at the time was already abundant enough to make byproducts like cheese for people in the desert who were in need of energy," he says.

Related: Chinese, German scientists discover world’s oldest cheese