Exogenous addition of muicle (Justicia spicigera Schechtendal) extract to white maize tortillas affects the antioxidant activity, texture, color, and in vitro starch digestibility

Abstract This work focused on the effects of adding of a polyphenol rich aqueous muicle (Justicia spicigera Schechtendal) extract (ME) to nixtamalized white maize flour, on the rheological properties of masa and on the texture, color, FTIR, antioxidant activity, and in vitro starch digestibility. NWMF with ME contents of x = 0, 0.7, 1.7, and 2.7 g.100 g−1 d.b. was used to prepare masa (Mx) and tortillas (Tx) variations. Increasing concentrations of ME had significant effects as follows: (i) Mx viscoelastic parameters decreased with G’>G’’; (ii) Tx hardness was unaffected, but extension at hardness, and maximum extension were increased; (iii) FTIR spectra indicated that hydration of the starch structures was improved; (iv) the enzymatic hydrolysis rate was lower; (v) the readily digestible and slowly digestible starch were reduced, and the resistant starch contents increased; (vi) polyphenols release and bioaccesibility under gastrointestinal conditions increased and so did the antioxidant activity by DPPH, ABTS and FRAP methods; (vii) color parameters were similar to that from blue maize tortillas; and (v) the moisture content of tortilla was improved under storage conditions. The addition of ME to white maize nixtamalized flour allows to tortillas in which starch digestibility can be modulated and blue maize tortillas color mimicked.