Abstract
On Tebing Tinggi Island, Riau, Indonesia, sago starch is no longer commonly used as a staple food; it is more common as an ingredient in cake-making. Following the traditional method of extracting the starch, the pith of two debarked logs, each ca.1 m long, was grated with a large grater. The pith was then spread on a platform covered with a nylon mesh sieve near a small river or pond and extracted by trampling it with watering. This study was conducted to clarify the starch extraction efficiency of the traditional method compared to chemical extraction. The percentage of starch extracted from the pith averaged 70.5%, which indicates that the logs were harvested at a suitable stage. The amount of starch extracted from the two logs using the traditional method averaged 32.3 kg, which was 48.0% of the chemically analyzed yield of 67.1 kg. The percentage of starch in the extracted residue was 55.7% on a dry weight basis, while the starch content of the extracted residue from the two logs averaged 35.1 kg or 52.1% of the chemically determined starch yield. Scanning electron microscope observations showed that no starch granules were present outside of the parenchyma cells of the pith after extraction, but numerous starch granules remained inside the parenchyma cells because the cell walls were still intact. On Tebing Tinggi Island, the efficiency of starch extraction from sago palm using the traditional method was about 50%. The low efficiency was attributed to incomplete grating of the pitch.
https://ror.org/01xxp6985 
