Risk assessment and characterizations of flaky rolls fortified with black rice (Oryza sativa L.)

Abstract This study aims to investigate the physicochemical composition, textural parameters, and chemical constituent of flaky rolls incorporated with different proportions of black rice flour. According to farinographic characteristics, the addition of black rice could reduce the stability and increase the dough development time and water absorption (%). According to extensographic properties, the addition of black rice resulted in significantly different maximum resistance to extension (BU) and extensibility (cm) versus the control. With the addition of black rice in flaky rolls, the crude protein, total dietary fiber (TDF), soluble dietary fiber (SDF), and insoluble dietary fiber (IDF) were significantly improved. Glucose released was much lower with 10% and 20% black rice than the control and 5% black rice because of the higher black rice inclusion. TDF, SDF, and IDF also increased. With increasing black rice incorporation, total anthocyanin content was also increased, as was total phenolic content, 2,2-diphenyl-1-picrylhydrazyl, and oxygen radical absorption capacity. The content of asparagine, acrylamide, hydroxymethylfurfural, furfural, methylglyoxal, and glyoxal in flaky rolls was also increased. The proper content of black rice flour (5%) could significantly enhance the stability of the dough properties; control the final volume, texture, and appearance; and retain good protein and fiber composition, antioxidant capacity, and overall acceptance of the flaky roll.