“Shitsugi”, a traditional aging method of Awamori in Okinawa, uses a series of Kame(clay vessels) similar to the solera system of sherry wine. However, it is not clear what effect this has on the flavor characteristics of Awamori. Therefore, we held a “Shitsugi” Kusu(aged Awamori) and Treasured Awamori Competition to investigate the flavor characteristics of “Shitsugi” Kusu. A sensory evaluation using the QDA(Quantitative Descriptive Analysis) method was carried out on submitted Awamori samples. Results of sensory evaluations showed a tendency for the “Shitsugi” Kusu to have high aging flavor characteristics. Furthermore, Kame stored Awamori was found to be less pungent than bottled stored Awamori.
The changes in sake making properties of sake rice were investigated during storage of brown rice grains under 4~30℃ for 24 months in two kinds of moisture contents. Significant changes in sake making properties of sake rice--except for a small increase of potassium concentrations--have not been observed when the brown rice grains have been stored under 10℃ at the rice warehouse in Hyogo Prefecture and under 4℃ and 10℃ at NRIB for 24 months. On the other hand, the broken rice ratio of a milling test, potassium concentrations of polished rice, and viscosity at RVA have increased during storage of brown rice under 30℃ at NRIB for 6 months. Although the hexanal concentrations in brown rice have increased during storage even under 4~10℃, those in polished rice have not been detected during storage under 4~10℃ for 24 months. The present study suggested that the sake making properties of sake rice would not deteriorate either by both storing rice grains under 10℃ or maintaining the moisture content of rice grains without changes in moisture.
In order to clarify the difference in flavor characteristics of aged and non-aged Awamori, sensory evaluation using the QDA(Quantitative Descriptive Analysis) method and chemical analyses were carried out on Kusu(aged Awamori) and Ippanshu(non-aged Awamori) brands entered in the 2019 Awamori Awards. Results of the QDA evaluation showed that the flavor characteristics of “Dried fruits”, “Caramel”, “Sweet flavor”, “Vanilla” were strong for the aged Awamori, while the aged Awamori was weak for “Mushroom”. The flavor characteristic of “Caramel” was strong in the clay vessel storage Kusu.