The effect of sago starch on the textural properties of straight (80°C, 20 min) and two-step (30°C, 30 min - 80°C, 20 min) heating gels of walleye pollack frozen surimi was studied and compared with that of potato starch. The addition of sago starch to surimi increased the breaking strength, elongation and gel strength of both straight and two-step heating gels less than the addition of potato starch. Although the 30°C preheating increased the gel strength, it had little effect on the function of either starch. The addition of sago starch made the surimi gel lighter (higher in Hunter L) and more yellow (positive in Hunter b) than that of potato starch. The observation of the microstructure of starch-added gel by natural scanning electron microscopy clearly showed that the granule size of sago starch in the surimi gel network structure is smaller than that of potato starch. The findings suggest that sago starch has less capacity than potato starch for forming gel because sago starch swells less than potato starch.

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 The effect of the heating temperature (80, 90°C) after preheating at 30°C for 30 min on the textural properties of walleye pollack frozen surimi gel with 4% sago and potato starch was investigated. The gel strength of the sago starch-added gel and the potato starch-added gel heated at 80°C was two times and three times higher than that of the control gel, respectively. On the other hand, heating at 90°C made the textural properties of all gels higher than heating at 80°C. These properties of the sago starch-added gel reached almost the same level as those of the potato starch-added gel. The L and b values (Hunter) of sago starch-added gel heated at 90°C were lower than those of the gel heated at 80°C and almost the same level as those of the potato starch-added gel. Using a natural scanning electron microscope, it was observed that the size of sago starch granules in the 90°C-heated gel was larger than that in the 80°C-heated gel, although the potato starch granules in the 90°C-heated gel were similar in size to those in the 80°C-heated gel. The above results showed that, when sago starch-added surimi is heated to 90°C rather than 80°C, the gel properties become almost the same as those of potato starch-added gel. This is probably because the sago starch granules swell more at 90°C than at 80°C.

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 The sago palm is one of the highest yielding perennial starch crops in the world. Starch is accumulated progressively in the trunk and each palm is capable of producing about 200kg of dry starch. Because of the continuous production of off-shoots to replenish the harvested palm, the economic life of sago palm is theoretically perpetual. It is one of the very few crops that are highly tolerant to low pH and can be cultivated on peat and sulphidic soils.
 The growth of sago palms on deep peat without maintenance and added nutrient is far inferior as compared to those grown under shallow peat and mineral soils. The soil water pH of the three studied gardens are between 3.8 to 4.6, slightly higher than the normal range of 3.2 to 4.0 found in Sarawak.
 Under minimal drainage and maintenance on deep peat, about 20% of the 10-15 year-old sago palms produced trunks but none attained maturity. They possess 6-10 fronds and their trunk lengths and diameters are 1-4 m and 41 cm respectively.
 On deep peat with seasonal flooding, less than 10% of the sago palms produced trunks at 8 years after planting. In contrast, over 80% of sago palms on shallow peat produced trunks at 5-6 years after planting and possess a crown size of 12-15 fronds. They attained maturity at 10-11 years, with trunk lengths and diameter of about 8 m and 45 cm respectively.

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