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Limited studies have been reported on the interaction of elephant foot yam (EFY) starch and hydrocolloids. Hence the present study investigated the effect of hydrocolloids (agar-agar, AAG and xanthan gum, XG) concentration (0.5, 1, 1.5 and 2%) on pasting, rheological, thermo-functional and morphological properties of EFY starch. The increase in concentration reduced the swelling index and enhanced the solubility. Peak, holding, break down and set back viscosity was highest at 2% XG than AAG. Dynamic storage modulus (G′) was higher than loss modulus (G″) within frequency range with an increase in hydrocolloids concentration. Pasting temperature reduced from 77.20 to 49.7 °C (AAG) and 77.20 to 61.56 °C (XG). FTIR exhibited differences in peak absorbance and broadness of O H and C O stretching at 3400–3200 cm−1 and 1260–1000 cm−1 upon hydrocolloids' addition. Increased AAG concentration reduced the peak temperature of gelatinization and retrogradation of EFY starch. The effect of hydrocolloids and their concentrations on the higher binding of EFY starch molecules and crystallinity has also been supported by SEM images. These results show that EFY starch with hydrocolloids can be used as a thickener. Its good binding ability may be explored for the possible applications in bakery industry and for the development of edible packaging film.

The present study focused on the effect of microwave treatment (300 W for 1, 3 and 5 min) on the physicochemical, morphological, structural and rheological properties of potato starch. Significant effect (p 0.05) of treatment time was observed on water activity and moisture content while non-significant effect occurred on color. Water absorption capacity increased from 0.82-1.16 g/g with treatment time while oil absorption capacity decreased from 0.63-0.53 g/g. Dynamic and loss moduli, pasting temperatures and final viscosities were positively correlated with treatment time. The peak and pasting viscosity incremented till 3 min treatment but decreased at 5 min. Onset temperature of gelatinization ranged from 53.8 to 57.4 °C with treatment time. SEM micrographs showed unaffected starch granules at 1 min of treatment while fissures and indentations developed at 3 and 5 min. The X-Ray diffraction patterns indicated the transformation of starch crystals from B crystallite to amorphic type.