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In this study, starch citrates were synthesized by superheated steam (SS) treatment without changing the granule structure of starch. The degree of substitution (DS) of starch citrates prepared in present study was ranged from 0.015 to 0.064. Fourier transform infrared spectroscopy confirmed that citric acid (CA) and starch were successfully esterified with an absorption peak appeared at 1735 cm−1. In vitro digestion results revealed that the content of resistant starch (RS) was significantly increased by citric acid esterification, which was attributed to the cross-linked structure of starch and the inhibition of gelatinization and swelling. According to the physicochemical properties analysis, the pasting temperature of rice starch citrates were significantly increased by citric acid treatment, while the swelling power and gelatinization enthalpy were significantly decreased and the short- and long-range molecular order of the starch was disrupted after the esterification reaction. These results indicated that it is a feasible method to synthesize starch citrate by superheated steam to increase resistant starch, and it could be used as an alternative approach for preparing starch citrate to conventional hot air treatment. • A superheated steam technology was adopted to synthesize starch citrates. • The starch citrates were maintaining the granule structure of starch. • The resistant starch content was increased by the formation of starch citrates. • The esterified and cross-linked structure was formed in starch citrates. • The inhibition of gelatinization and swelling was found in starch citrates. [ABSTRACT FROM AUTHOR]