Steam bread made by superfine purple corn flour: Texture characteristics and in vitro starch digestibility

Abstract

The performance of purple corn flour (PCF) with various size pulverized by low temperature impact mill (LTIM) in making steamed bread was investigated. Results indicated that decreased diameter of PCF showed richer red with increased a* (4.43–7.34), stronger adhesiveness (0.04–2.25 N s), more appropriate hardness (15.20–48.30 N), lower water fluidity (T2, ranged from 19.05 to 14.12 ms), and more cross-linking structure to purple corn dough (PCD). PCD texture characteristics were significantly affected by starch network and filler-like effect of dietary fiber based on the additional adding dietary fiber to starch. Steamed bread made by finer size PCF (56 μm) exhibited favorable quality supported by smooth skin, regular shape, porous structure, appropriate texture properties and low starch digestibility, which was mainly due to the higher α-amylase inhibitory activity of dietary fiber. These results confirmed that using PCF prepared by LTIM could be a suitable option to get good-quality whole grain food.