title: Soaking and extrusion effects on physicochemical parameters, phytic acid, nutrient content and mineral bio-accessibility of whole rice grain.
abstract: A combination of soaking and extrusion processes of whole rice grain was studied. The effects of temperature (35-55 °C) and time (24-48 h) of soaking treatment on phytic acid (PA), protein and ashes losses using a factorial design were evaluated. Taking into account ash, protein and PA losses, whole rice was soaked 24 h at 45 °C and extruded using a Brabender single screw extruder. Effects of extrusion temperature (160-190 °C) and moisture content (14-19 g/100 g) on product characteristics were evaluated using surface response methodology. Values corresponding to the different responses were: Expansion (1.64-3.28), Specific Volume (5.68-11.06 cm(3)/g), Water absorption (3.41-4.43 mL/g) and Solubility (45.44-66.20 g/100 g). The content of PA was reduced from 740.09 to 163.47 mg/100 g (77%) after both processes, resulting in a higher mineral bio-accessibility, and a 7.3% decrease of protein digestibility. Total soluble phenolics and trolox equivalent antioxidant capacity (TEAC) were affected according to the treatment. Both treatments were important to obtain a nutritionally improved whole grain product.
authors: Facultad de Ingeniería Química, Instituto de Tecnología de Alimentos, Universidad Nacional del Litoral , Santa Fe , Argentina and.
authors: Micaela
authors: M
authors: Albarracín
authors: Rolando
authors: R
authors: José González
authors: Silvina Rosa
authors: SR
authors: Drago
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology; D001682:Biological Availability; D004032:Diet; D004044:Dietary Proteins / Q000032:analysis; D004063:Digestion; D005504:Food Analysis; D005511:Food Handling / Q000379:methods*; D006801:Humans; D008903:Minerals / Q000032:analysis*; D009753:Nutritive Value; D012275:Oryza / Q000737:chemistry*; D010636:Phenols / Q000032:analysis; D010833:Phytic Acid / Q000032:analysis*; D012639:Seeds / Q000737:chemistry; D013696:Temperature; D014867:Water; D000067348:Whole Grains / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D004044:Dietary Proteins; D008903:Minerals; D010636:Phenols; D014867:Water; D010833:Phytic Acid
keywords: Bio-accessibility extrusion; phytic acid; rough rice; soaking; whole grain