To clarify the influence of the sago palm (Metroxylon sagu Rottb.) on the soil through phytolith formation, a transmitted-light microscope was used to determine the particle size, the number of conical projection spines (CPS), the vertex angle of the CPS, the length of the bottom of the CPS, and the height of the CPS of spheroid echinate phytoliths in spined and spineless sago palm leaflets and the soil surface from Pangasugan, Leyte, Philippines. The sago palms were transplanted from the Dulag area in the eastern part of Leyte in 2005, and leaflet samples were taken in 2016. The spined sago palm provided the smaller mean particle size, larger number of CPS, larger CPS vertex angle (131.8±12.5°), larger length of the bottom of CPS, and smaller height of CPS than those of the spineless sago palm. On the other hand, the CPS vertex angle of the spineless sago palm was 85.1±10.9°. Two angle peaks of CPS on the spheroid echinate phytoliths from 81 to 140° with one shoulder of 111 to 120° were found in the surface layer soil samples taken in 2019. Based on the CPS characteristics, it is concluded that the spheroid echinate phytoliths on the soil surface were transported from both the spined and spineless sago palm in the sago palm field of Pangasugan, Leyte.

Sensorial properties of cookies made of sago (Metroxylon sagu Rottb.) and its mixture with taro (Colocasia esculenta L. Schott) starch were evaluated to develop new effective utilization of sago and taro starch, which obtained from the intercropping in Leyte, Philippines. Cookies were made from sago starch and taro starch with different composition: 0% (control), 5% and 10% of taro starch was used instead of sago starch, which were named cookie A, B, and C, respectively. Cookies of 100% sago starch with different diameters or thicknesses were prepared as D and E, respectively. Cookies characteristics were evaluated by appearance, sweetness, hardness, crispness, and comprehensive evaluation by the panelists recruited from the 10 university students of 20s. The score of appearance, sweetness, and comprehensive evaluation of cookie D was the highest, 7.4, 7.8, and 6.0, respectively. Although sugar content was same for all cookies, score of sweetness was different for each cookie and was the most effective for comprehensive evaluation of sensory evaluation. Since cookie D has a larger diameter, total amount of sugar became larger than other cookies. In addition, bearing resistance of cookie D was significantly lower than other cookies, so it was speculated that it was easy to crumble, spreads quickly in the mouth and was digested quickly. These were presumed to be the reason for the high sweetness score of cookie D. Our results suggested that intercropping of sago and taro is effective to produce taro starch, which will be potential materials to make several kinds of cookies.

The consumer price of sago starch and similar powdery starch obtained was investigated at the retail stores of 8 companies chosen from different classes to cover various level of consumers’ income and the official online stores. The analyzing price of sago starch was compared with the main similar starches such as flour, tapioca starch, rice starch, and the unit price of sago starch remained higher position compared with tapioca, potato and rice starch or flour. The offline price was much higher than online price in sago starch. There were four categories of sago type starch produced by sago palm (Metroxylon sagu: M.s) and sugar palm (Arenga pinnata: A.p) online. The mean value of unit price was highest in ‘Sagu’ (M.s), followed by “Sagu Aren Murni’ (A.p), ‘Sagu Aren’ (A.p) and ‘Sagu Rumia’ (M.s). As the results of the principal component analysis in M.s employing the package weight, package price, price promotion sale, unit price and order number, two interaction PCs were extracted. Larger package with expensive price per package will be negative factor and the promotion sale of more expensive quality ones will be positive factor for larger order number. The cheaper starch that is sugar palm starch was considered to attract consumers’ attention rather than sago palm in average. Contrarily, when the starch variations in each species are compared (between Sagu and Sagu Rumbia (M.s) or between Sagu Aren Murni and Sagu Aren (A.p), more expensive starch considered as quality ones will attract consumers’ preference in average.

It is well known that property differences in sago starch can arise due to such factors as sago variety, production area, cultivation environment, and purity level. With this in mind, the objective of this research was to compare a total of nine types of sago starch, including sago starches sold in Indonesia and sago starches imported to Japan from Indonesia. A focus was also put on gluten-free, which is receiving much attention nowadays, and the development of gluten-free pasta made with sago starches imported to Japan was attempted. Nine varieties of sago starch produced in Indonesia were used in the property comparison of various commercial sago starches. Their viscosities at a starch concentration of 7.5%, and the physical properties of starch gels kept at 5℃ for two hours, were compared. For production of the gluten-free pasta using sago starch, first a gel with 18% starch concentration was made using 15g sago starch and 80g distilled water heated in a saucepan. Then, 40g of the gel, 54g of corn flour, 1g of xanthan gum, and 2g of olive oil were kneaded together, and pasta dough was prepared. With the aim of suppressing retrogradation, 3%, 5%, and 7%, of the sago starch was substituted with two types of modified starch (hydroxypropylated tapioca starch (HP), and acetylated distarch phosphate and enzyme-treated starch (APE)). Creep meter (breaking strength test) and sensory evaluation tests were used for analysis. Results obtained were: 1) The nine Indonesian sago starches showed remarkable differences in quality, in their viscosities, and in the physical properties of their gels. 2) Non-cooked pasta substituted with modified starch (HP and APE), showed a tendency to be softer than pasta made with sago starch, but after boiling, the hardness of the pastas was similar. 3) 15 minutes after boiling, the hardness of the sago pasta roughly doubled. However, when 5%, or 7%, of the sago starch was replaced with the two types of modified starch, a tendency for the increase in hardness to be suppressed was seen, meaning, retrogradation suppression could be confirmed.

When non-glutinous rice flour used for karukan preparation was substituted with other starches, differences were observed in the expansion of karukan. In this paper, non-glutinous rice flour was substituted for sago starch, which is expected to improve the utilization and palatability of karukan, and the results were compared with those of karukan made with other starches.

Reference karukan was prepared in a food processor using Yamatoimo (Japanese yam), non-glutinous rice flour, white sugar, and distilled water. Sago, corn, wheat, potato, sweet potato, and cassava were used as starch substitutes for non-glutinous rice flour. Moistures were determined by heat drying method under the atmospheric pressure and viscosities were measured for the crushed Japanese yam by Viscometer. Specific volume of karukan was obtained by dividing the volume using canola seed method by the weight. Texture measurements were performed on the karukan by Creep meter. Sensory evaluation was conducted using a 7-point scoring method to evaluate relative strengths and preference.

Karukan with 100% substitution of sago starch for non-glutinous rice flour was significantly lower preference than the reference in the sensory evaluation. On the other hand, the karukan with 50% sago starch substituted for non-glutinous rice flour did not differ significantly from the reference in terms of all the determined value. Though in terms of preference, the appearance and color items were significantly lower, there were no significant differences in the good texture, taste, hardness, and springiness items. Therefore, the starch replacement ratio was decided to 50% in subsequent experiments. The physical properties of the karukan prepared showed that all starches tended to have higher values for hardness than the reference, while potato and cassava starch had the same level as the reference for adhesiveness, and the other starches had smaller values. The appearance and color of the karukan substituted with sago and cassava starches were lower in the sensory evaluation preferences. This may be due to the light grayish color of sago starch product, while the cassava starch product showed lower swelling, resulting in a gelatinous product with less foams. In the overall evaluation, potato starch was significantly less preferred than the reference and corn starch. However, sago starch showed no significant differences from the sweet potato, wheat, cassava and potato starches. While some panels liked the distinctive light pink color of sago starch karukan, others said it tasted a little astringent. This suggests that improving the taste of sago starch would improve the preference of sago starch karukan.