トチノミ食から見た三信遠国境山地・身延山地・秩父山地周辺の地域差 Regional Differences in Horse Chestnut Processing in the San-Shin-En Border Range, Minobu Range, and Chichibu Range Areas
The horse chestnut is distributed mainly in the heavy snowfall areas of eastern Japan. It is a deciduous broad-leaf tree which together with beech trees composes valley forests. Raw horse chestnuts (buckeyes) cannot be eaten raw because they contain bitter tannic components such as aloin and alkaloid. It is thought that the method for removing tannic acid from buckeyes was discovered in the latter half of the mid-Jomon period, when buckeyes were a staple food. The custom of eating buckeyes originally diffused from the east to the west in Japan, and presently it is moving from east Japan to Okuhida and its environs in Gifu prefecture and to Tajima and neighboring districts in Hyogo prefecture.<br> We studied regional differences in the processing of buckeyes in Japan in: 1) the San-Shin-En border range extending through Aichi, Nagano, and Shizuoka prefectures; 2) the Chichibu range area extending through Saitama, Gunma, and Yamanashi prefectures, and the Tokyo metropolitan area; and 3) the Minobu range area in Yamanashi prefecture, which was previously little studied.<br> In the San-Shin-En border range area people follow the ancient custom of gathering buckeyes and use traditional preservation methods. Thus we find <i>chirikisebu</i> (the custom of buying a mountain forest excluding the buckeyes), <i>yoraidochi</i> (the traditional system of gathering buckeyes and distributing them equally), and <i>narikizeme</i> (the traditional ceremony of breeding trees), and Jomon-type processing methods, including <i>kozawashi</i> (buckeyes processed in water and boiling bleaching in the Hida highland area) and farm-type processed buckeye cakes. It is clear that people in the San-ShinEn border range area have depended on the buckeye as a food source for a long time. The traditional method for removing the tannic acid from buckeyes (<i>neriaku</i>) in this area is excellent. Although in the past it was customary to peel buckeyes with the teeth, the people here now use a wooden tool (<i>tochimuki</i>) to peel them, which is called an <i>anguri</i> in this area. The southern part of the Shinano district is well known for using <i>tochimuki-ishi</i> (stone for peeling buckeyes), which is called a <i>tataki-ishi</i> or <i>tenshi</i>.<br> Jomon-type processed buckeye foods are found throughout the Chichibu range area, including <i>tochizarashi</i> (buckeyes processed with water and boiling bleaching in Otaki village). It is still customary to peel buckeyes with the teeth. The <i>neriaku</i> method is also used for removing tannic acid. Although the <i>tochimuki</i> is not found in this area, it is most advanced in the use of <i>tochimuki-ishi</i>.<br> Processed buckeye foods in the Minobu range area are the same as in the San-Shin-En border range areas in terms of the method of acid removal, but the people in the Minobu range area use tools for peeling buckeyes similar to those used in the southern Shinano district and the Chichibu range area.<br> The results of this study show that Jomon-type processed buckeye foods are more widely distributed throughout, Japan than previously thought. In addition, the two cultural elements of Jomontype processing and peeling buckeyes with the teeth can be thought of as one set in terms of distribution.<br> Although we cannot depend on field work to determine regional differences in processed buckeye foods, the study of ancient documents and literature will become more important in future studies of this type.
- 地理学評論. Ser. A
地理学評論. Ser. A 70(1), 28-42, 1997-01
The Association of Japanese Geographers