Starch isolated from carica papaya was modified by treatment with sodium monochloroacetate.. Proximate analyses revealed that moisture, ash, fat, protein and carbohydrate increased after carboxymethylation. But, percentage fibre content reduced from 11.46% in native starch to 9.69% in carboxymethyl starch derivative. The carboxymethylation reaction was confirmed by the presence of new intense bands at 1600 and 1419 cm-1 associated with the carboxyl and carboxymethyl substituents of the etherifying agent. The starch exhibited higher water and oil absorption capacities following modification and least gelation concentration reduced in carboxymethylated starch but increased in native starch. The blue value of starch-iodine colour complex, and turbidity stability decreased and improved respectively after carboxymethylation. Carboxymethylated starch showed a significantly lower pasting temperature, peak viscosity, trough viscosity and setback viscosity as compared to native starch. Differential thermal analysis results showed that the carboxymethylation altered the thermal behavior of carica papaya starch.
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