Synthesis of octenyl succinate pineapple starch and evaluation for its application as nanoemulsion stabilizer

Abstract

The stem and rhizome waste of pineapple plant (Ananas comosus L. Merr.) is normally disposed of via a burning process, which can cause environmental pollution. In order to improve the limited properties of native pineapple starch (NPS) and to minimize waste, pineapple starch extracted from stem and rhizome was synthesized by octenyl succinic anhydride (OSA) using a fractional factorial central composite face centered (CCF) design. The Fourier transform infrared (FTIR) spectra results showed that new peak formation of ester carbonyl groups was found at 1716 cm−1 for octenyl succinate pineapple starch or OSA modified pineapple starch (OSAPS), indicating that the synthesis of pineapple starch by OSA was successful. Moreover, optimization of reaction conditions of OSAPS with multiple responses was successfully performed using response surface methodology (RSM). The OSA concentration was found to be the principal factor for the degree of substitution (DS), surface tension, and enthalpy model. The obtained OSAPS showed an increase in viscosity, clustering of granules and a decrease in surface tension, gelatinization temperature and enthalpy when compared with NPS. Moreover, the functional properties of OSAPS such as surface & interfacial tension, viscosity and emulsifying activity index were evaluated in order to apply as nanoemulsion stabilizer. An increase DS of OSAPS tended to statistically decrease the surface tension, interfacial tension, and increase the viscosity (p

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