Journal Article

Isolation of Cassava Starch and Synthesis of Acetyl Derivatives Using Vinegar

Abstract

This study was carried out to assess and establish the changes in physicochemical parameters of cassava starch (CS) after modification using mercerization and acetylation. Substituted starch acetate was prepared by reaction of native CS with commercial vinegar and NaOH. The modification was confirmed by the titrimetric analysis and Fourier Transformed Infrared Spectroscopy. The presence of absorption band in FT-IR Spectra for acetylated samples confirmed the success of modification. The scanning electron microscopy (SEM) of samples suggested that acetylation at low temperature gave rise to smooth surfaces of CS granules, while at high temperature; the smooth surfaces of starch granules were changed into fibrous morphology after acetylation. Mercerization at long time also gave rise to fibrous surfaces of starch granules. Acetylated samples gave high solubility index more than both mercerized and native samples. Acetylation products at higher temperature showed high swelling power than native samples. Samples that were acetylated for 150 min. had a decrease in swelling power while the water absorbing capacity of the acetylated samples was also high compared to native starch samples.

Download pdf