The Yomiuri Online covers research that has increased the quantity of ornithine in sake threefold.
This amino acid is found in Japanese shijimi clams, and is alleged to be effective against hangovers and aid in recovery from fatigue. (And now that I think back to my BSc and how to present evidence - or avoid doing so - the ability of the Japanese language to avoid a subject comes in pretty handy.)
The high-ornithine sake was developed by the Nara Prefecture Institute of Industrial Development in association with Nara Institute of Science and Technology (NAIST). I gō (合, 180 ml) is said to provide the same quantity of ornithine as 50 clams. Ōhashi Masataka, a researcher at the Prefectural Institute who was seconded to NAIST in 2013, discovered a strain of yeast that produces 13 times as much ornithine while carrying out screening studies. He conducted brewing trials with the Nara Prefecture Sake Association, and local brewery Yagi in Nara City used the yeast in one of their commercial sake, tanrei-karakuchi (light and refreshing, sweet) junmai Shōhei last autumn. The amount of ornithine produced during sake brewing was less than in culture, but the prefecture and NAIST obtained a patent for the brewing process regardless.
Sake is not eligible for the Japanese functional food labelling system, so it cannot make claims such as "good for the liver", but the high-ornithine sake lacks the characteristic bitterness of the amino acid and is said to be easy to drink. Ōhashi cautions that drinking too much of it will indeed result in a hangover. A 720 ml bottle costs JPY 1,188 (including tax) and the sake is 15% abv.
I'm sure you can all hear me shouting at my screen from wherever you are. This is a triumph of biotechnology and screening and brewing, sure, but even joking about a 15% abv product being "good for your liver" is enough to make me want to ask people to hand in their scientist cards.
I had a quick look online to try to figure out how much ornithine is in a clam, and how much ornithine is supposed to be enough to cause an effect, so I can figure out if "50x the ornithine of a clam" is meaningful, but if the information is out there it's hard to find among the claims of shijimi curing your hangover, and your liver while they're at it.
Anyway. I love sake, but alcohol is not and never will be a health product. If that's what you're worried about, go eat some clams. Bon appetit.
- Original article (Japanese, Yomiuri Online, 6 March 2018)
- Yagi brewery (Japanese)
- United States Department of Agriculture report on the 2015 changes to Japanese functional food labelling (English, PDF) Contains links to regulatory information in Japanese.
- Sake Experience Japan story about Nara sake made with yeast from double cherry blossoms and taken from shrine grounds (English, Sake Experience Japan, 4 January 2017)