2021 年 65 巻 2 号 p. 75-83
On Muna Island, Southeast Sulawesi, Indonesia, approximately 10 sugar palms were planted in a residential area and used mainly to collect sap from male inflorescences to be used for beverages or palm liquor (arak). The number of male inflorescences for sap collection was 3–15, and the periods of this collection for each inflorescence and per plant were 1–8 months and 2–5 years, respectively. When the color of the male flower changed from green to dark brown, the periphery of the stalk’s base and the trunk above it were pounded with a mallet to promote the sap flow. This was collected in a plastic tank or an unglazed pot with or without Buli (dried bark of Xylocarpus granatum) in the early morning and evening. Its volume was slightly higher in the former, and the average in total was approximately 6 L plant-1 day-1. Three types of sugars―sucrose, glucose, and fructose―were detected in the sap. The sucrose content was the highest without Buli, and the Brix reading was 12.5% on average; however, with Buli, the total sugar content and the Brix reading decreased to about 1/7 and about 1/2 of those without Buli, respectively, and the proportion of glucose and fructose contents increased, while that of the sucrose content decreased. In addition, the pH decreased and the temperature increased in the morning sap with Buli.
