Preparation and Physicochemical Properties of Pregelatinization-Composite Enzymatic Digestion of Rice Flour with Embryos for Infants and Children

Abstract

To prepare high quality rice flour for infants and toddlers with embryonic rice as raw material, the application of pregelatinization-composite enzymatic digestion in the processing of rice flour for infants and toddlers and its effect on physicochemical properties were studied. The process conditions of the best composite enzymatic digestion technology were obtained by single-factor and orthogonal tests. And the effects of the enzymatic process on the surface morphology, water solubility index and water absorption index, brewing dispersion, solubility and pasting characteristics of the infant retained embryo rice flour were also investigated. Results showed that: Total addition of composite enzyme 1250 U/g, enzymatic digestion time 150 min, enzymatic digestion temperature 58 ℃, DE value (Dextrose Equivalent) 33.08%±0.33%, WSI 0.823%±0.07%, overall score 1.012. The water absorption index, dispersion time and viscosity of the rice flour made by pre-dextrinization-enzyme digestion were significantly lower (P<0.05), and the water solubility index and solubility were significantly higher (P<0.05) compared with the untreated rice flour with embryo retention and pre-dextrinized rice flour. As summary, the rice flour obtained by pre-dextrinization-composite enzymatic digestion had the advantages of low viscosity, good brewability and digestibility.

Keywords

• pre-dextrinization
• compound enzymatic hydrolysis
• embryonic rice
• infant rice flour
• water absorption index
• water solubility index
• gelatinization characteristics