The science behind it

TSUNAN SAKE BREWERY measured a nanoparticle fraction purified from GO GRANDCLASS and published the report. Here is what is known, and what has not been tested.

What was measured

The brewery extracted and purified a nanoparticle fraction from GO GRANDCLASS Uonuma Koshihikari Edition, quantified it by nanoparticle tracking analysis (NTA), and published a report in Japanese and English.

Date

16 January 2026

Sample

Nanoparticle fraction purified from GO GRANDCLASS Uonuma Koshihikari Edition (measured at 50× dilution)

Instrument

NanoSight NS300 (blue laser, 405 nm)

Mode size

152.3 nm (± 4.3 nm)

Concentration

1.26 × 10¹⁰ particles/mL (± 2.38 × 10⁹), adjusted for the 50× dilution

Source: Nanoparticles detected in GO GRANDCLASS (TSUNAN SAKE BREWERY)

• Reading the size. The mode falls within the exosome size range (roughly 30–200 nm, the scale of extracellular vesicles). That means the size matches. It does not confirm the particles are exosomes.
• Likely origin. The fermentation process, involving yeast and koji mold, may generate nano-scale particles.
• Next. Compositional analysis (proteomics, lipidomics) and evaluation of biological activity are planned.

SAKESOME — the research theme

TSUNAN SAKE BREWERY calls its research on sake-derived nanoparticles SAKESOME. In the brewery's words, the work is about "fractionating beneficial micro-components contained in sake at the nanoparticle level, with potential applications in cosmetics, food products, and agricultural materials," with collaborative research with universities currently underway.

SAKESOME is one theme of the brewery's Sake Upcycle Project (launched July 2025): the application research strand devoted to sake-derived nanoparticles. The measurement above is a result from GO GRANDCLASS related to this theme.

Stated carefully

What is established is the measurement: exosome-size particles were detected in a purified fraction. Their functional activity is still under study—so this is described as the opening of a field at the intersection of brewing and nano-bioscience, not as a health claim. The taste and quality stand on their own; the nanoparticle data is a measured fact placed beside them, not a promise of effect.

Presented in research settings

On 20 January 2026, GO GRANDCLASS was presented at a frontier seminar at Institute of Science Tokyo (Yushima campus). This was a research exchange, and it does not indicate any health effect from drinking the sake.

On 16 September 2026, brewery president Kengo Suzuki spoke at the 78th Annual Meeting of the Society for Biotechnology, Japan (Hokkaido University) on developing a branded sake from table rice with generative AI. For Koshihikari, hard to work with because of its stickiness, protein and lipids, generative AI proposed a low-temperature, long-fermentation profile. Feared undissolved rice did not occur, and an off-flavor indicator stayed within the predicted range (PR TIMES, in Japanese). See the journey.