While examining the fluid dynamics behind whisky “mellowing” would appear to be the perfect dissertation topic for a high-living doctoral student, Japanese distillery Suntory is serious about studying the impact of microgravity on its signature products. Serious enough to send five kinds of whisky (along with 40% ethanol as a sixth control sample) via the Kounotori 5 transfer vehicle to the International Space Station (ISS) to mature for two years.
Expected to take off from the Japan Aerospace Exploration Agency's Tanegashima Space Center on August 16, inclement weather caused a postponement of the launch of the Japan Aerospace Exploration Agency (JAXA) H-IIB rocket until tomorrow, Aug. 19, at 7:50 a.m. EDT.
Alcoholic beverages (with the exception of some items like beer) are widely known to develop a mellow flavor when aged for a long time. Although researchers have taken a variety of scientific approaches to understanding the underlying mechanism, they still do not have a full picture of how this occurs. Suntory has hypothesized that “the formation of high-dimensional molecular structure consisting of water, ethanol, and other ingredients in alcoholic beverages contributes to the development of mellowness,” and they have been conducting collaborative research on this topic with the research groups of Professor Shigenao Maruyama of Japan’s Institute of Fluid Science at Tohoku University and Professor Mitsuhiro Shibayama of the Institute for Solid State Physics at the University of Tokyo, as well as with the Japan Synchrotron Radiation Research Institute and Suntory Foundation for Life Sciences. The results of these collaborative research efforts suggest “the probability that mellowness develops by promoted formation of the high-dimensional molecular structure in the alcoholic beverage in environments where liquid convection is suppressed,” according to Suntory.
On the basis of these results, the space experiments will be conducted in the ISS’s Japanese Experiment Module (nicknamed “Kibo”), to verify the effect of the convection-free state created by a microgravity environment to the mellowing of alcoholic beverages. One set of samples consisting of various alcoholic beverages will be stored in a convection-free state in Kibo on the ISS and another set of the identical samples will be stored in Japan for the same period of time. The following methods will be then used to analyze and compare the two sets of samples.
1. Measurement of substance diffusion coefficient with the use of a phase-shifting interferometer in cooperation with the Institute of Fluid Science, Tohoku University.
2. Detection of high-dimensional structure by small angle X-ray scattering, in cooperation with the Japan Synchrotron Radiation Research Institute and the Institute for Solid State Physics, the University of Tokyo.
3. Measurement of substance diffusion with the use of the NMR method, in cooperation with the Suntory Foundation for Life Sciences.
With less gravity suppressing convection, there’s a possibility that the low-gravity environment will accelerate the whisky’s aging, causing a two-year batch to taste like it has been aged for a ten years. The samples’ age ranges from a freshly distilled whisky to a 21-year single malt. For a variety of reasons (launch weight restrictions, etc.) the whisky is stored in glass flasks rather than wooden barrels.
The unpiloted Kounotori cargo craft will also be loaded with more than 4.5 tons of other research materials and supplies, including water, spare parts and experiment hardware for the six-person space station crew.