The amylopectin chain distribution of sago starch collected from Papua New Guinea (PNG) and the Philippines (PLP) was studied using a high-performance ion-exchange chromatograph (HPIC) equipped with a pulsed amperometric detector (PAD). The branch chain lengths with the degree of polymerization (DP) 6–12 (Gr1), DP 13–24 (Gr2), DP 25–36 (Gr3), and DP≧ 37 (Gr4) designated as short, intermediate1, intermediate2, and long amylopectin chains were 25% (Gr1), 58% (Gr2), 12% (Gr3), and 4% (Gr4) (peak area percentage) for PNG and 25% (Gr1), 60% (Gr2), 12% (Gr3), and 4% (Gr4) for PLP, respectively. Both PNG and PLP sago starches possessed a greater abundance of short amylopectin chains (Gr1) than those of corn and potato starches.

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 Associated with the sago potency in South Sulawesi Province, the role of sago farm households (SFHs) becomes more important because they dominate and run most sago processors. However, a limited number of studies have focused on SFHs in Indonesia, particularly in South Sulawesi Province. This study’s goal is to identify the factors contributing to differences among SFHs’ production of sago. A total of 54 valid questionnaires were collected from SFHs in the Malangke Barat subdistrict, a subdistrict in Luwu Utara Regency, during July and August 2015. The obtained data were analyzed using statistical independent t-test analysis to determine statistical differences between the means of two groups. Based on the test (significant at the 1% level), SFH1 has higher working hours, higher income, and higher motivation than SFH2. SFH1 allocates 5.34 hours/day, while SFH2 only allocates 2.46 hours/day for sago processing. SFH1 can earn IDR 8.69 million/month (1 USD = 13,000 IDR exc. rate April 25, 2017), while SFH2 can only earn IDR 2.19 million/month from sago. Furthermore, SFH1 believes that sago is profitable and promising, while SFH2 is only involved in sago production to support their economic lifestyle without any further goals. Undeniably, motivational training and support from related stakeholders can encourage the SFHs to work to achieve a better livelihood.

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 Sago residue after starch extraction contains a considerable amount of starch. In this study, we aimed to develop a simple and effective method for producing bioethanol from sago residue. Starch in sago residue was efficiently liquefied with thermostable α-amylase at 90 °C using a mass ratio of sago residue to α-amylase solution of 1:6. The liquefied solution (approximately 100 g/L sugar) was subjected to both separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes to produce ethanol. In SHF, glucose prepared with α-amylase and amyloglucosidase was almost consumed by yeast after 36 h of fermentation at 37 °C, and 34.2 g/L ethanol was produced with a yield of 66.0%. In SSF, 43.2 g/L ethanol was obtained with a yield of 86.4% after 72 h of saccharification and fermentation at 37 °C using the liquefied solution with added amyloglucosidase and yeast. This has been the highest ethanol concentration ever reported in bioethanol production from sago residue.

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