Physicochemical and Nutritional Properties of Nixtamalized Quality Protein Maize Flour and its Potential as Substitute in Philippine Salt Bread

Abstract

Nixtamalization is an ancient method of processing corn that is said to enhance the nutritional value of maize by improving protein quality, increasing calcium and niacin bioavailability, and reducing phytic acid levels, thus increasing iron digestibility and biovailability. The main objective of this study was to determine the effect of different nixtamalization processes on the physicochemical and nutritional properties of quality protein maize (QPM) flour and evaluate its potential and acceptability as a flour substitute in Philippine salt bread baking, determined through sensory analysis. Three processes of nixtamalization were employed, namely, traditional, classic, and ecological. Nixtamalized QPM flours, combined with wheat flour in 30:70 ratio, were used in the product development and sensory evaluation of Philippine salt bread. Results revealed that nixtamalization contributed significantly in the pH, color, and particle size of nixtamalized QPM flours. There was a significant increase (P ≤0.05) in the moisture, crude protein, crude fiber, crude ash, calcium, iron, niacin, lysine, tryptophan, total starch, amylose, amylopectin, resistant starch, and soluble fiber contents and a significant decrease in the crude fat, nitrogen-free extract (NFE), phytate, and insoluble fiber contents of QPM flours after nixtamalization. No significant difference was found in the zinc and total dietary fiber contents among the samples. The Philippine salt bread produced using nixtamalized QPM flours had a high overall acceptability based on two-step sensory analysis. QPM is greatly improved by the ancient technology of nixtamalization and nixtamalized QPM flour showed desirable contributions in terms of the nutritional value and sensory attributes of Philippine salt bread when used as a flour substitute or blend.

Quality protein maize: nutritional and bioactive composition, technological attributes and potential food applications

“…The results indicated by Farinde (2019) depicted that nixtamalisation improved niacin, lysine and available lysine in the treated QPM flour. A significant decline in the antinutrients, crude fat, nitrogen‐free extract and insoluble fibre contents of QPM flour was observed in nixtamalised samples (Sunico et al ., 2021). Studies conducted by Guria (2006) indicated that the in vitro protein digestibility of the QPM flour was found quite higher than normal maize.…”

Nutrient composition, starch microstructure and thermal properties, and in vitro availability of selected minerals of nixtamalized Philippine quality protein maize variety IPB Var 6 and the production of healthy loaf bread using nixtamalized corn–wheat flour blends

“…Moreover, IPB Var 6 flour has been used in combination with other starchy foods like rice, wheat flour, and sweet potato to produce more nutritious food products (Hernandez et al, 2022;Juanico & Hurtada, 2019;Maloles & Hurtada, 2018;Nguyen-Orca et al, 2014;Sunico et al, 2021;Tabuac et al, 2019).…”

“…IPB Var 6 contains 66.2% more lysine than regular local white corn and has significant amounts of minerals and phytochemicals such as iron (3.72 mg/100 g), zinc (2.37 mg/ 100 g), potassium (228 mg/100 g), calcium (72.16 mg/100 g), magnesium (137 mg/100 g), total phenolics (4.18 g GAE/100 g), total flavonoids (5.29 mg CE/100 g), and total carotenoids (0.73 mg/100 g) (Purificacion et al, 2018). Moreover, IPB Var 6 flour has been used in combination with other starchy foods like rice, wheat flour, and sweet potato to produce more nutritious food products (Hernandez et al, 2022; Juanico & Hurtada, 2019; Maloles & Hurtada, 2018; Nguyen‐Orca et al, 2014; Sunico et al, 2021; Tabuac et al, 2019).…”

“…Nixtamalization is the boiling, soaking, and washing of corn in an alkaline solution to obtain the nixtamal (Wacher, 2003). The traditional method involves the preparation of a lime solution wherein the corn grains are boiled and then steeped for 8–16 h. Nixtamalization reportedly improved corn's resistant starch content (Mariscal Moreno et al, 2015), induced the formation of the amylose‐lipid complex (Santiago‐Ramos et al, 2017), altered textural attributes (Amador‐Rodríguez et al, 2020), increased the micro‐ and macronutrient contents (Sunico et al, 2021), and reduced phytic acid content, thereby increasing the availability of selected minerals (Bressani et al, 2002; Bressani et al, 2004).…”

Food Processing Technologies to Develop Functional Foods With Enriched Bioactive Phenolic Compounds in Cereals

“…The process involves cooking corn in an oversaturated alkaline solution, typically, calcium hydroxide solution, for 30–40 min followed by steeping for 8–16 h. The cooked corn kernels, called nixtamal, are rinsed to remove excess lime and ground ( Serna-Saldivar and Rooney, 2015 ; Niu and Hou, 2020 ). This technique dissolves the hemicellulose, alters its rheological properties, promotes protein bonding, reduces antinutrients and aflatoxins to enhance the dietary value of cereals ( Schaarschmidt and Fauhl-Hassek, 2019 ; Cabrera-Ramírez et al, 2020 ; Kamau et al, 2020 ; Luzardo-Ocampo et al, 2020 ; Sunico et al, 2021 ). The nixtamalization method has also been investigated as a technology for increasing the number of phenolic chemicals in food ( Salazar-López et al, 2018 ).…”