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Surface modified tapioca starch was developed by enzyme treatment (using STARGEN™ 002 enzyme) and alcohol-enzyme treatment. The effects of acetylation treatment on surface modified tapioca starches were evaluated for acetyl content (Ac%), degree of substitution (DS), morphology using scanning electron microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), thermal properties, and X-ray diffraction (XRD) patterns. After acetylation treatment, Ac% and DS value of the samples were significantly increased for acetylated (0.67% and 0.03), enzyme-acetylated (1.13% and 0.04), and alcohol-enzyme acetylated (1.76% and 0.07). The acetylation treatment led to the formation of a few starch granules due to the introduction of hydrophilic groups of acetyl molecules into starch granules. The incorporation of acetyl groups into starch molecules also was shown at peak 1750 cm-1 , 1369 cm-1 , and 1230 cm-1 in the FTIR spectra. The enzyme-acetylated and alcohol-enzyme acetylated starch granules retained the A-type crystalline structure with decreased in the gelatinization enthalpy (ΔH) after acetylation.

Surface‐modified tapioca starch is produced via alcohol/alkali pre‐treatment, followed by enzymatic hydrolysis (using STARGEN 002 enzyme). The effects of alkali and alcohol pre‐treatments on tapioca starch are analyzed in terms of fat and protein content, degree of hydrolysis, morphology properties using scanning electron microscopy (SEM), thermal properties, and adsorption of linalool. The alkali and the alcohol pre‐treatments are able to significantly decrease the fat content of tapioca starch by 94–95% and the protein content by 12.5–50%. After 24 h of hydrolysis, dextrose equivalent (DE) value is significantly increased for the alkali‐enzyme hydrolysis (87.54%), and the alcohol‐enzyme hydrolysis (61.45%) as compared to the enzyme hydrolysis (56.23%), and the native starch (0.44%). The chemical‐enzyme hydrolysis increased the wavenumber ratio value 1047 cm−1/1022 cm−1 (WR1047/1022) values from 1.12–1.47 cm–1/cm–1, as well as the degree of crystallinity but, does not alter the X‐ray diffraction pattern. The alcohol‐enzyme hydrolysis starch showed the highest adsorption efficiency toward linalool (44.94%) due to its deep surface erosion and porous structures, as shown by the SEM results. The alcohol‐enzyme hydrolysis starch is found to be a suitable carrier material for linalool.

The study of chitosan loading onto epoxidized natural rubber compounds were prepared by incorporation of chitosan into epoxidised natural rubber matrix using a two-roll mill. The effects of chitosan loading on the curing characteristics, tensile properties and morphology of the compounds were investigated. Results indicated that slight changes in curing time (t90), and scorch time (tS2) of the compounds with the incorporation of chitosan. An increment is observed in the maximum torque, tensile modulus and durometer hardness of the compounds while tensile strength and elongation at break declines with chitosan loading.