Tsunan Brewing Co., Ltd. (Tsunan, Niigata, Japan; President & CEO: Kengo Suzuki) has conducted a quantitative analysis of nano-scale particles contained in its flagship sake, GO GRANDCLASS Uonuma Koshihikari Edition, using Nanoparticle Tracking Analysis (NTA), a technique widely employed in exosome research. The analysis confirmed the presence of nanoparticles in the exosome-size range (approximately 150–180 nm) at high concentrations within the sake.
Background and Objectives
In recent years, extracellular vesicles (EVs) derived from fermented foods and plant sources have attracted increasing attention in the field of health science. Exosomes—nanoscale extracellular vesicles approximately 30–200 nm in diameter—are at the forefront of life science research for their role in intercellular communication, and studies are now beginning worldwide on how EV-like nanoparticles in foods may affect the human body.
Tsunan Brewing focused on the possibility that Japanese sake, born from the power of rice, water, and fermentation, may also contain such nano-scale particles. The company selected its flagship product, GO GRANDCLASS Uonuma Koshihikari Edition, for exosome purification and NTA analysis.
Analytical Methods
Nanoparticle Tracking Analysis (NTA)
The purified sample was subjected to NTA using a NanoSight NS300 instrument. NTA irradiates a sample with laser light and individually tracks the scattered light from nanoparticles undergoing Brownian motion, enabling real-time measurement of particle size distribution and concentration.
Measurement Conditions
| Instrument | NanoSight NS300 (Blue laser, 405 nm) |
| Date of Measurement | January 16, 2026 |
| Dilution | 50× |
| Camera Level | 12 |
| Detect Threshold | 5 |
| Replicates | 5 measurements averaged |
Results
NTA analysis of the purified fraction from GO GRANDCLASS Uonuma Koshihikari Edition detected nanoparticles in the exosome-size range at high concentrations. Key results are summarized below.
Particle Size Distribution and Concentration
| Parameter | Result |
| Mean Particle Size | 180.8 nm (± 3.3 nm) |
| Mode Particle Size | 152.3 nm (± 4.3 nm) |
| Standard Deviation (SD) | 47.2 nm |
| D10 | 134.4 nm |
| D50 (Median) | 170.0 nm |
| D90 | 232.8 nm |
| Particle Concentration | 1.26 × 10¹⁰ particles/mL (± 2.38 × 10⁹) |
* Particle concentration reflects the 50× dilution factor.
Key Findings
The mode particle size was 152.3 nm, falling within the established exosome size range (30–200 nm). The particle size distribution showed D10 = 134.4 nm and D90 = 232.8 nm, indicating a relatively uniform distribution concentrated in the 100–250 nm range.
The particle concentration was approximately 12.6 billion particles per mL (1.26 × 10¹⁰ particles/mL), an exceptionally high value. This suggests that the sake fermentation process, involving yeast and koji mold, may generate abundant nano-scale particles.
Significance and Future Outlook
This analysis represents a pioneering effort to quantitatively demonstrate the presence of exosome-sized nanoparticles in Japanese sake. While NTA measures the presence and concentration of nano-scale particles in a sample and does not directly prove the biological origin or function of these particles, the ability to visualize the nanoscale composition of sake carries significant scientific value.
Going forward, Tsunan Brewing plans to pursue compositional analysis of these nanoparticles (proteomics, lipidomics, etc.) and evaluate their bioactivity, aiming to uncover new functional properties and added value in sake. By pioneering the intersection of brewing and nanobiotechnology, Tsunan Brewing seeks to deepen both the cultural appreciation and scientific understanding of Japanese sake.
