Sago starch is a locally abundant starch indigenous of Indonesia. Despite its abundance, it is underutilized and restricted to food and packaging applications due to its limited functional characteristics. The value of native sago starch can be increased through modifications that improve its functionality, such as dual chemical modification. This sophisticated approach is more effective than single modification and makes the starch suitable for wider applications. Our study aimed to determine if dual chemical modification involving hydroxypropylation and succinylation would optimize the functional properties of sago starch. The sago starch was first modified by hydroxypropylation with 7 % (w/w) propylene oxide under alkaline conditions for 3 hours. This process resulted in hydroxypropylated starch with a substitution degree of 0.107. We then subjected the starch to succinylation using succinic anhydride at 1 % to 5 % of the starch weight in an alkaline solution for 2 hours.We achieved optimal functional characteristics of the dual-modified sago starch in the sample modified with 3 % (w/w) of succinic anhydride. The succinyl degree of substitution, water holding capacity, oil holding capacity, swelling power, and solubility of the dual-modified starch were 0.093, 4.16 g g⁻¹ , 7.20 g g⁻¹, 34.25 g g⁻¹, and 16:55 %, respectively. We conducted pasting properties analyses, infrared spectroscopy, and morphological structure analysis to determine the changes in the characteristics of the sago starch after hydroxypropylation and succinylation. The dual chemical modification successfully enhanced the functional characteristics of sago starch, particularly, its amphiphilic ability and swelling power. These results warrant further research and development in commercial applications.

Cassava pulp is used to develop dietary fiber from prospective local resources to boost its added value and applications. Extrusion and an acid-heat treatment were used to alter cassava pulp into nutritional fiber. The goal of this study was to characterize the chemical compositions, physical-chemical functional features, and yield of dietary fiber products produced by the extrusion and acid-heat processes. Total dietary fiber (TDF) content was 89.24%, starch content was 9.7%, water holding capacity (WHC) was 12.07 g/g, oil holding capacity (OHC) was 3.99 g/g, swelling capacity (SC) was 17.8 ml/g, bulk density (BD) was 0.2 g/ml, and yield was 50% for the dietary fiber produced by the acid-heat treatment. While the extrusion process produced dietary fiber with TDF content of 50.86%, starch content of 47.28%, WHC of 9.96 g/g, OHC of 0.81 g/g, SC of 12.99 ml/g, BD of 0.6 g/ml, and a yield of 90%. Acid-heat treatment was successful in eliminating starch constituents, raising TDF, and raising WHC and OHC values. The extrusion procedure did not raise TDF or OHC and could not eliminate components of starch, however, it might increase WHC by swelling the starch granules.