Stanford students recreate 5,000-year-old Chinese beer recipe

So the recipe was arrived at by reverse-engineering residues in pottery vessels, and not written down 5000 years ago. In contrast, the Hymn to Ninkasi, which contains an ale recipe, was written down in Sumerian on clay tablets 4000 years ago. Translation at http://www.piney.com/BabNinkasi.html

"The students first covered their grain with water and let it sprout, in a process called malting. After the grain sprouted, the students crushed the seeds and put them in water again. The container with the mixture was then placed in the oven and heated to 65 degrees Celsius (149 F) for an hour, in a process called mashing. Afterward, the students sealed the container with plastic and let it stand at room temperature for about a week to ferment."

The heat would have killed off any yeast in the wort, and sealing the container would have prevented any yeast getting in after the wort cooled, so this cannot be correct. The correct process is to boil the wort, let it cool down, and leave it outside (or open the windows) to allow wild yeast (Saccharomyces cerevisiae) and other microorganisms to blow in and inoculate the wort. This process is called spontaneous fermentation, and is still used in Belgium to produce Lambic. Spontaneous fermentation causes bacteria (Lactobacillus and Acetobacter species) to also settle in the wort, eventually turning the beer sour. In other beer styles, yeast is deliberately added after the wort cools.

"The ancient Chinese beer looked more like porridge and likely tasted sweeter and fruitier than the clear, bitter beers of today."

It's an ale rather than a beer. To be a beer, it would have had to contain hops, which give beer its bitterness and act as a preservative. Unless drunk very quickly, like Lambic it would have also gone sour.

Also, the story is at least misleading: they did not discover a recipe. They found trace particles on the walls of pottery. You don't just collect the ingredients of a baked good and then claim you have a recipe. There's quite a bit more to actually making it.

How do they know what they were examining ("ancient beer would have looked more like porridge") wasn't just the mash or sparge stages of beer making, which often looks like porridge?

Here's an account of one guy who tried to make beer (and bread) using semi-ancient methods: https://www.morebeer.com/brewingtechniques/library/backissue... I like that his experiments produced an actual hypothesis as to the origins of brewing:

"This test was not a complete waste, however. Though it should perhaps be repeated in a warmer climate, it indicated that the earliest beer was not likely produced by the simple accident of grain being soaked by rainwater. The earliest beers likely did not appear until some process for mashing or malting was developed, either in the form of a gruel or a sprouted bread."

http://usa.chinadaily.com.cn/world/2017-03/20/content_286203...

Full disclosure, the brewery is owned by a friend of mine, but I have no financial stake in the company.

  At the end of Liu’s class, each student tried to imitate the ancient Chinese beer using either wheat, millet or barley seeds.

  The students first covered their grain with water and let it sprout, in a process called malting. After the grain sprouted, the students crushed the seeds and put them in water again. The container with the mixture was then placed in the oven and heated to 65 degrees Celsius (149 F) for an hour, in a process called mashing. Afterward, the students sealed the container with plastic and let it stand at room temperature for about a week to ferment.

  The ancient Chinese beer looked more like porridge and likely tasted sweeter and fruitier than the clear, bitter beers of today. The ingredients used for fermentation were not filtered out, and straws were commonly used for drinking, Liu said.