Effect of traditional nixtamalization on anthocyanin content and profile in Mexican blue maize (Zea mays L.) landraces

• Anthocyanin profiles of 15 Mexican blue maize landraces from Sinaloa were estimated.
• Acylated anthocyanins were predominant in blue landrace from northwest of Mexico.
• Nixtamalization process of blue maize diminished anthocyanins.
• Anthocyanins retention of tortillas from six blue maize ranged from 45 to 70%.

Mexican blue maize (Zea mays L.) grains have been poorly evaluated regarding their potential as functional food ingredients. The aims of this research were to identify and quantify anthocyanins from fifteen Mexican blue maize accessions of Elotero Sinaloa landrace recollected in the northwestern region of Mexico. Additionally, the effect of traditional nixtamalization processing on these compounds was evaluated. The acyl type anthocyanins, such as cyanidin-3-(6″-succinylglucoside) (Cy-Suc-Glu) and cyanidin-3-(6″-disuccinylglucoside) (Cy-diSuc-Glu) were the most abundant compounds in blue maize, accounting for 52.1% and 15.6% the total anthocyanins, respectively. Other predominant anthocyanins included cyanidin-3-glucoside (Cy-3-Glu), pelargonidin-3-glucoside (Pg-3-Glu), pelargonidin-3-(6″-malonylglucoside) (Pg-Mal-Glu) and cyanidin-3-(6″-malonyglucoside) (Cy-Mal-Glu). The raw blue maize presented a similar anthocyanins profile dominated by cyanidin derivatives on (86.9% on average). Nixtamalization processing increased the relative percentage of glycosylated anthocyanins (Cy-3-Glu, and Pg-3-Glu) and decreased the acylated anthocyanins (Cy-Suc-Glu, and Cy-diSuc-Glu) when compared to raw kernels. Results obtained indicate that the studied Mexican native blue maize contained anthocyanin patterns predominated by acylated cyanide derivatives. This information could be useful to select the best pigmented maize for the derivation of food products with nutraceutical potential.