Structural, functional, thermal and rheological properties of nixtamalised and extruded blue maize (Zea maysL.) flour with different calcium sources

Abstract

Summary The effects of different concentrations of calcium hydroxide [Ca(OH)2] and calcium lactate [C6H10O6Ca] on the functional and physical properties of extruded (EF) and nixtamalised (NF) blue maize flours were evaluated. Calcium source and concentration showed no significant effects on the EF expansion index. The water absorption index (WAI) of EF decreased as the concentrations of both calcium sources increased, and NF with C6H10O6Ca had the lowest WAI. The thermal and pasting properties of NFs were higher than those of EF. NF with C6H10O6Ca showed the highest final viscosity (FinV), indicating less damage to the starch granules, and this was correlated with microscopic analysis. In contrast, the FinV of EFs was significantly affected by calcium source and concentration. Extrusion with 0.3% and nixtamalisation at 2.95% of C6H10O6Ca yielded high WAI value and the best rheological properties in maize flour, respectively. These results suggest the use of C6H10O6Ca in extrusion or nixtamalisation to produce blue maize flours for tortilla or snacks with antioxidants.

Physicochemical, Thermal, and Sensory Properties of Blue Corn (Zea Mays L.)

“…Carrera and others () reported that the onset, peak, and end gelatinization temperatures of raw blue corn flour were 61.34 °C, 70.12 °C, and 83.15 °C and the gelatinization enthalpy was 7.10 J/g. Another study, the onset, peak, and end gelatinization temperatures and gelatinization enthalpy of blue corn were reported as 62.9 °C, 69.3 °C, and 75.9 °C and 7.0 J/g, respectively (Sánchez‐Madrigal and others ). The gelatinization temperatures were nearly similar with literature, but the gelatinization enthalpy was lower.…”

“…Thermal properties of whole blue corn flour were determined by differential scanning calorimeter (DSC 6000, PerkinElmer Inc., Wellesley, U.S.A.). The analysis was performed according to Sánchez‐Madrigal and others (). For this aim, 2 mg of milled and sieved (212 μm sieve) flour sample was placed into an aluminum pan and after adding of 20 μL distillated water into flour, the pan was closed.…”

Effect of different calcium sources on the antioxidant stability of tortilla chips from extruded and nixtamalized blue corn (Zea mays L.) flours

“…This difference can be attributed to the formation of complexes of the starch with the calcium resulting in a more compact (Zazueta-Morales et al, 2002) molecule and therefore harder tortilla chips. This texture difference between both calcium sources could be due to the lower ionization of C 6 H 10 O 6 Ca than that of Ca(OH) 2 , which did not result in the release of Ca 2+ (Sánchez-Madrigal et al, 2014). In general, the force of fracture of TCEF is higher than that of TCNF; TCNF with C 6 H 10 O 6 Ca showed the lowest peak force values.…”

Effect of Different Corn Processing Techniques in the Nutritional Composition of Nixtamalized Corn Tortillas

“…This last practice was observed in tortilla shops and it is made with the aim of whitening and softening the product, as well as to help stop spoilage. On the other hand, calcium concentration affects tortilla moisture: at higher concentrations water absorption into starch is reduced [29]. This may explain the lower moisture in MD tortillas.…”