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Native starch was isolated from two corn landraces (blue and white) and a hybrid variety and then characterized for its physicochemical, thermal and rheological properties. The hybrid variety showed the highest starch yield, with its starch showing the highest fat, moisture and protein content but the lowest onset temperature of gelatinization. The hybrid corn starch also showed the highest G' and G" values. The tested starches showed similar T p , T c , and ΔH values. The amylose contents ranged from 21.5 to 22.4%, with starch from blue corn showing the highest amylose content. All starches were white, with L values ranging from 93.6 to 99.5. The light absorbance of the starch gels increased with storage time. The obtained results demonstrated that the physicochemical, thermal and rheological properties of corn starch are highly dependent on the corn type.

Starches from the Macho (Musa paradisiaca L.) and Roatan (Musa sapientum L.) banana varieties were chemically modified by sodium trimetaphosphate (STMP) cross‐linking. Cross‐linking affected the pasting properties of the modified starch, with more pronounced changes observed in the Macho variety than in the Roatan starch. In turn, this result indicated that the former starch source is more susceptible to STMP cross‐linking. The swelling and solubility profiles exhibited an important decrease with cross‐linking, which was caused by increased ordering of the internal granule structure induced by cross‐linking modifications. The gelatinization temperature and enthalpy increased due to cross‐linking, indicating an improvement in the starch granule stability. Englyst's in vitro digestibility studies of the modified starch were performed to estimate the content of rapidly digestible (RDS), slowly digestible (SDS) and resistant (RS) starch fractions. It was shown that STMP cross‐linking increased the RS content of the two banana varieties. However, the SDS content increased only for the Macho variety. In general, the viscosity was lower for the modified starches than for their native counterparts. The results of the current work indicate that the chemical modification process via STMP cross‐linking offers an interesting alternative for obtaining RS from banana starches.