Effects of Anthocyanin-Rich Popping Maize Flour on the Phenolic Profile and the Antioxidant Capacity of Mix-Bread and Its Physical and Sensory Properties
Polish Journal of Food and Nutrition Sciences
Dr. Slađana Žilić) studies concerning the enrichment of wheat bread with different small grain cereals, cereal by-products and pseudo-cereals, as well as spices, fruits and herbs in the order to produce bread with improved antioxidant properties [Yousif et al., 2012; El-Megeid et al., 2009] . However, studies of blue and dark-red maize fl our used for this purpose are rare. Anthocyanins are the main antioxidants in colored maize grains. Studies have shown that the main anthocyanins present in
... lored maize were identifi ed as cyanidin-3-glucoside, pelargonidin-3-glucoside, and peonidin-3-glucoside, along with their corresponding malonyl derivatives [Žilić et al., 2012]. Recent results of Mora-Rochín et al.  have shown that the acyl type anthocyanins, such as cyanidin-3-(6-succinyl glucoside) and cyanidin-3-(6-disuccinyl glucoside) were the most abundant compounds in blue colored maize, accounting for 52.1% and 15.6% the total anthocyanins, respectively. It should be noted that monomeric anthocyanins possess limited stability against hydration, pH changes, temperature and light exposure [Dangles et al., 1993] while recent studies have shown that the anthocyanins with acylating substituents were more stable during processing and storage [Bąkowska-Barczak, 2005] . A partial substitution of white wheat fl our with wholegrain anthocyanin-rich maize fl our can greatly improve functional properties, as well as the nutritional value of bread. Nevertheless, it poses considerable technological diffi culties because maize proteins lack the ability to form the necessary gluten network for holding the gas produced during dough fermentation. Key words: anthocyanin-rich popping maize fl our, bread, phenolic profi le, anthocyanins, antioxidant capacity, physical and sensory properties In this study, the effect of anthocyanin-rich popping maize fl our on phenolic profi le, antioxidant capacity and color of bread were investigated. Texture and sensory properties of maize mix-breads were evaluated also. Replacing 30% of wheat fl our with blue-and dark-red-seeded maize fl ours increased the content of total phenolic compounds, ferulic and p-coumaric acids of mix-breads compared to the control bread. In addition, anthocyanins from maize fl ours improved functional profi le of breads. Despite thermal degradation, the content of anthocyanins in crumb of blue and dark-red maize mix-breads was high and amounted to 142.3 mg CGE/kg and 84.4 mg CGE/kg, respectively. In his acylated and non-acylated forms, cyanidin 3-glucoside was the most prevalent anthocyanins in maize mix-breads. However, given to the synergistic and antagonistic interaction that arises from the coexistence of numerous antioxidant compounds in food, anthocyanin-rich maize fl our had no effect on the increase in the bread antioxidant capacity. Anthocyanin-rich maize flour changed the bread crumb color to a red range. Although maize mix-breads had worse textural properties compared to the wheat bread, their sensory quality was improved.