China—a land renowned for delicious dumplings, the giant panda, an impressive wall, and … beer?
Earth’s most populous country currently holds the title of most prolific beer producer, and now artifacts from northern China suggest that the country can claim one of the oldest beer making facilities in the world.
The 5,000-year-old brewery also provides the earliest evidence of barley in China, suggesting that the thirst for suds may have spurred the initial movement of the crop to the area.
“This is the earliest direct evidence of beer in China to our knowledge,” says study leader Jiajing Wang, a doctoral student at Stanford University. “And the finding of barley was a surprise, because we really didn’t expect to find barley dated that early.”
In 2004, a separate archaeological team excavated two subterranean pits in Mijiaya, a site on a tributary of the Wei River in the Shaanxi Province. The pits, measuring about 12 feet (3.7 meters) and 8.5 feet (2.6 meters) deep, each housed a variety of clay artifacts, including wide-mouth pots, funnels, and narrow-mouthed vessels with a pointed bottom. Many of these artifacts had yellow residue on the inside surface.
The archeologists also found the remains of a primitive stove in each pit. Based on the unique pottery style, the team deduced that the containers were likely from the late Yangshao period, which dates to between 3,500 and 2,900 B.C.
When Wang and her team reviewed these findings, which were published in a 2012 report, a new interpretation bubbled up. Based on the remains, they concluded that the Mijiaya site might be one of humankind’s first microbreweries, equipped with instruments for each stage of the beer-making process—pots and a stove for mashing and brewing, funnels for filtration, and storage vessels for the finished product.
To test this hypothesis, Wang and her team isolated grains in the yellow residue inside the vessels and used large databases and statistical analyses to identify them based on unique starch and mineral structures.
Their results, published May 23 in the Proceedings of the National Academy of Sciences, showed a high presence of barley, millet, and Job’s tears (an ancient grain-bearing tropical plant that’s currently having a gluten free moment), along with ingredients such as snake gourd root, yam, and lily.
“This is a very interesting recipe,” says Wang. “The barley is from the West and is not indigenous in this region. The other ingredients—mainly the broomcorn millet, the Job’s tears, and the tubers—are indigenous to China. So it is a drink mixed with both traditions, Chinese and Western.”
In addition to giving the beer a unique local flavor, these unusual ingredients likely served another purpose: creating more alcohol.
“Humans were interested in upping the sugar content so they could get more alcohol, and would take whatever they could get in their environments and mix them together,” says Patrick McGovern, the scientific director of the Biomolecular Archaeology Project at the University of Pennsylvania Museum, who was not associated with the study. “So it is pretty typical to see a mixed beverage, or what we call an extreme fermented beverage.”
Layers of Evidence
Identifying grains commonly involved in beer production is still not proof that brewing actually took place. But a subsequent microscopic analysis showed that the grains had been damaged—pits and channels were found on their surfaces and many of them were swollen, distorted, or fused with one another.
These changes matched perfectly to the typical alterations grains experience during the malting and mashing stages of the brewing process.
To bolster the results, the researchers conducted a chemical analysis of the grain residue on several of the vessels. Their findings showed high levels of oxalate, a hallmark byproduct of the brewing process and the primary component of beerstone, the calcium deposits that accumulate during barley beer fermentation.
And to make sure that the sediments lining the inside of brewing equipment were not contaminated by the surrounding soil, Wang and her team analyzed material from outside the vessels, as well as other stone fragments from within the pit. They found little evidence of any grains used for brewing and no chemical presence of the oxalate compound.
“The combination of evidence here is really impressive,” says McGovern. “It’s not just the botanical, but it is also the chemical and the archaeological evidence. So you have a beer-making facility that you can make a really good case for.”
The Beer Road
Although the Chinese had been using rice to make alcoholic beverages as early as 9,000 years ago, this is the first indication of barley in ancient China, suggesting that the demand for its intoxicating byproducts motivated the initial movement of the crop into the region before it was fully integrated into farming 3,000 years later.
According to McGovern, brewing facilities similar to those at Mijiaya have also been discovered in Egypt and Iran dating back to around 3,400 B.C., suggesting that knowledge of this brewing process may have accompanied the spread of barley through trade routes.
Each of these fermentation operations contained comparable wide mouth pots and heating stoves that provided sufficient air and heat for enzymes to break down the starches, as well as narrow-mouthed storage containers that could be closed to prevent the alcohol from turning into vinegar.
In future work, Wang and her team hope to expand their research to additional regions and time periods.
“This study is just the start of our research on the origins of alcohol production in China,” she says. “We are planning to analyze more artifacts to explore how alcohol production is related to ritual practices, plant domestication, and increasing social hierarchy in ancient China.”