Anatomical characteristics of starch accumulations and distribution in sago palm (Metroxylon sagu) stems of different ages of were investigated by a light microscope and a scanning electron microscope (SEM). Starch grains, which were elliptical or a bean-like shape and approximately 5-50 µm in diameter, were often observed in ground parenchymatous tissue at the outskirts of vascular bandle. They varied in size with palm age or height, in particular, starch diameter and their content began to increase in correspondence with the palm age. Furthermore, large medullary cavities developed in the all around of the ground tissue and there were not any starch grain in the cavities.

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 The sago palms (Metroxylon sagu) grow more slowly and take longer period to mature on peat soils than on mineral soils. Based on the two field experiments at Sungai Talau Peat Research Station, Sarawak, Malaysia, this article aimed to compare the root biomass distributions in tropical peat soils in relation to peat thickness and shoot growth, and to provide ecological information on sago growth. In experiment 1, sago root biomass was measured by taking soil blocks to a depth of 40 cm from the deep peat soil and from the alluvial mineral soil. Total fine root biomass of sago (d ≦ 5 mm) was larger in the alluvial soil (11.4 t/ha) than in the deep peat soil (4.7 t/ha), which contradicts the previous data on sago. The patterns of vertical distribution of roots in each diameter (= d) class were similar between the two soil types; the large roots (d > 5 mm) were distributed below 10 cm in depth and more than half of them concentrated in 20-30 cm layer, whereas fine roots (d ≦ 2 mm) and intermediate roots (2 < d ≦ 5 mm) allocated more than 60% and 55%, respectively, in 0-20 cm layer. The sago root distribution was not affected by the existence of other tree roots or large woody debris. In experiment 2, roots and shoots of one year sago palms were investigated. Both in deep and shallow peat soils, the shoot growths of the sample palms did not much differ and the roots extended below 1 m in depth only after about one year. Total numbers of first-order roots from the stump were larger in the shallow peat. But the difference became small when roots growing upward were excluded. The diameters of first-order roots were not significantly different. Collectively, total fine root biomass was smaller in the deep peat soil where sago palms grow slowly than in the alluvial mineral soil, and the pattern of vertical distribution of sago roots of three diameter classes (mentioned above) were similar between the two soil types.

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 Sago pearls are processed from sago starch that is stored in the trunk of sago palm. They look like white pearls that are 2-4 mm in diameter. Sago pearls are used as ingredients in soup or some desserts, for example, jelly or pudding like tapioca pearls. But it is difficult to get pure sago pearls. Therefore, tapioca pearls are used for cooking tropical foods of sago pearls.
 Pearl-type starch is difficult to cook, to get transparent, soft, flexible, and a uniform granule with good texture.
 In the previous papers, we discussed cooking methods of tapioca pearls and the effect of the addition of sugar. As a result, the most favorable cooking method was the thermos bottle method which gave good cooked states and good texture. In this study, we discuss a convenient and effective cooking method to give good cooked states and good texture of sago pearls.
 Two cooking methods, the thermos bottle method and the pan-boiled method were studied. Sago pearls (2 g: 106 tablets) were put into boiling water (300 ml), and cooked for various time periods from 0 to 80 minutes in the two methods. Texture properties of sago starch were estimated using creep meter (RE-3305, Yamaden Co.), and the cooking conditions were observed.
 The pan-boiled method gave soft and flexible pearls faster than the thermos bottle method. But the pan-boiled method gave ununiform states after cooking. The thermos bottle method, which required neither stirring nor supplying hot water during heating and gave good cooked states of sago pearls, was convenient and effective.
 In consequence, we expect that sago pearls can be used for many kinds of processed foods, if a large supply of pure sago pearls can be assured.

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