Pigmented Maize Research Articles

Retention of Phytochemical Compounds and Antioxidative Activity in Traditional Baked Dish "proja" Made from Pigmented Maize.

Two genotypes of pigmented maize (black (BM) and red (RM)) were used as flour ingredients in several formulations of the traditional baked maize dish "proja". This study investigated the stability of phytochemical compounds and antioxidant activity in proja as affected by baking and different acidity degrees of dough formulations. Compared to RM proja, all BM proja formulations were significantly higher in antioxidant compounds and exhibited the highest inhibitory activity (73-85%) against DPPH. There was a strong significant correlation between DPPH inhibition and total phenolics (r2 = 0.95), flavonoids (r2 = 0.96), and anthocyanins (r2 = 0.97) in baked proja. After baking, 67-85% of total phenolics were retained. The fate of flavonoids and anthocyanins after baking was variable: from 70% degradation to liberation. Dough acidity significantly and positively affected the content of phenolics, flavonoids, and anthocyanins in BM proja (r2 = 0.70, 0.82, and 0.47, respectively). Baking increased antioxidant activity against DPPH, •OH, and O2•- radicals in proja, except for ≈10% decline of DPPH inhibition in BM proja. In RM proja, retention of inhibitory capacity against O2•- was highly correlated to flavonoid retention (r2 = 0.71). Using pigmented maize flour in proja baking resulted in proja with appreciable content of total phenolics, flavonoids, anthocyanins, and high antioxidant activity, confirming the significant improvement of the nutrient profile of this traditional food.

Genetic characterization and evaluation of pigmented maize (Zea mays L.) landraces of the North East Hill Region of India-an established centre of maize diversity

Abstract The North East Hill Region (NEHR) of India is home to diverse maize landraces including pigmented accessions rich in antioxidants and nutritional properties. The present study attempted to characterize a representative collection of this mostly unexplored diversity. Altogether eighty-three local maize landraces from the seven hill states of the NEHR were studied with special emphasis on pigmentation diversity. For the morphological traits, a significant ANOVA indicated the presence of substantial genetic variability for which selection would be fruitful. A number of these accessions were found to have traits that help cope with moisture stress, improve stalk strength and optimize photosynthesis. Principal component analysis studies for the yield attributing traits indicated that ear weight was most variable. The bleaching/histological studies confirmed that anthocyanin pigment when present was always restricted to the aleurone layer of the kernels, typical of blue maize. Quantitative analysis for kernel anthocyanin/phlobaphene content also revealed genetic differences among the accessions. Genetic analysis using the model-based STRUCTURE indicated significant population structuring among the accessions. Specifically, for the pigmentation diversity studies both principal coordinate analysis and neighbour joining methods revealed near concurrent population structuring due in part to the high differentiation of seven of the twenty-one pigmentation specific loci studied. The results obtained provide comprehensive evidence of a significant amount of genetic differentiation among the landraces under study. Landraces are valuable reservoirs of favourable alleles for which selection can be made and, as in this study, identify accessions for breeding maize with enhanced levels of beneficial secondary metabolites.

Exploring the nutritional potential, anti-nutritional components and carbohydrate fractions of Indian pigmented maize

Seventeen pigmented maize cultivated in different locations of India were collected and evaluated for their nutritional, anti-nutritional and starch profile. A wide variation was observed in all the parameters evaluated. Protein and total dietary fiber content varied between 7.18 to 10.85 g/100 g and 8.76 to 14.04 g/100 g, respectively. Among the water-soluble vitamins, B2 varied from 0.071 to 0.134; B3, 1.50 to 2.79; B5, 0.17 to 0.70 and B6, 0.141 to 0.245 mg/100 g; while total tocopherol and tocotrienol varied 1417 to 2246 μg/100 g and 18.57 to 30.01 μg/100 g, respectively. The resistant starch, total starch and amylose varied significantly and observed between 0.49 to 4.78 %, 61.33 to 69.65 % and 10.91 to 32.01 %, respectively. Among the minerals, Fe and Zn were observed between 1.51 to 5.01 and 2.25 to 5.51 mg/100 g, respectively. Total polyunsaturated and total monounsaturated fatty acids were observed up to 45.72 and 55.54 %, respectively. Amongst the anti-nutrients, phytate was detected the lowest in Laal makki, whereas total and soluble oxalates were the lowest in Kashmiri red maize.

Novel Combination of the Biophysical, Nutritional, and Nutraceutical Properties in Subtropical Pigmented Maize Hybrids.

Maize (Zea mays L.) represents the main caloric source for much of the world's population. Pigmented maize varieties are an excellent source of nutraceutical compounds: blue and yellow maize are rich in anthocyanins as well as carotenoids and phenolic acids, respectively. However, blue maize is usually grown in small quantities as a specialty crop because it lacks the qualities and adaptations of commercial white and yellow varieties. Here, a new high-yield variety of blue maize called Vitamaiz was developed from inbred lines of subtropical blue, white, and yellow maize. The aim of this study was to characterize the nutraceutical and physical properties of 30 Vitamaiz hybrids in two subtropical locations. Kernel physical traits, nutrient composition, and nutraceutical components (free phenolic acids, FPA; cell wall-bound phenolic acids, BPA; total monomeric anthocyanin content, TAC; antioxidant capacity, AOX by oxygen radical absorbance capacity assay, and total carotenoid content, TCC) were evaluated. The biophysical traits of the hybrids were suitable for nixtamalized and flour maize industries. High levels of FPA (228 mg GAE/100 g), BPA (635 mg GAE/100 g), and AOX (2.0 and 8.1 mM Trolox equivalent/100 g for FPA and BPA, respectively) were also detected with elevated TAC levels (274 mg C3G/kg dw) and AOX activity (3.1 mM Trolox equivalent/100 g). This is the first study to characterize Blue × Yellow maize hybrids that adapt to subtropical environments.

Effect of consumption of blue maize tortilla on anxiety-like behaviour, learning, memory and hippocampal BDNF expression in a chronic stress model in rats

ABSTRACT Background Pigmented maize consumption is of much interest because of its high anthocyanin content and multiple health benefits. Objetives: This study was aimed to assess the effect of consuming blue maize tortillas on the anxiolytic capacity, preserve emotional memory, and the expression of brain-derived neurotrophic factor (BDNF) in rats subjected to chronic stress. Methods: Sixty-four 3-month-old male Wistar rats were used, divided into eight groups (n = 8). Four groups were subjected to chronic stress by movement restriction (7 h/daily/7 consecutive days) and the remaining four groups were subjected to standard management. The treatments were commercial food, blue tortilla, anthocyanin extract, or white tortilla, administered for nine weeks to stressed or unstressed animals. In the eighth week, the animals were subjected to the restraint stress model. Subsequently, anxiety-like behaviour was assessed using the elevated plus-maze, and memory and emotional learning were evaluated by the step-down passive avoidance test. The animals were then sacrificed to quantify the relative expression of hippocampal BDNF by RT-qPCR. Results: The consumption of anthocyanin extract or tortilla made with blue corn decreased anxiety-like behaviours, additionally, it improved the ability to retain emotionally relevant information, and it upregulated BDNF mRNA expression. Perspective: Thus, the analyse of the impact of blue tortilla consumption on the nervous system is now necessary to guarantee the nutraceutical value of this food.

Diversity of the Peruvian Andean maize (Zea mays L.) race Cabanita: Polyphenols, carotenoids, in vitro antioxidant capacity, and physical characteristics.

The high diversity of the Peruvian Andean maize (Zea mays L.) represents a biological and genetic heritage relevant for food security, but few studies are targeted toward its characterization and consequent valorization and preservation. The objective of this study was to evaluate the potential of the Peruvian Andean maize race Cabanita with respect to its bioactive profiles (free and bound phenolic and carotenoid composition), physical characteristics, and in vitro antioxidant properties. Maize landraces with variable kernel pigmentation were collected from two provinces (Caylloma and Castilla) within the Arequipa region (among ten Andean sites) and the phytochemical profile was evaluated by Ultra High-Performance Liquid Chromatography with diode array detector (UHPLC-DAD). All maize samples were important sources of phenolic compounds mainly soluble p-coumaric and ferulic acid derivatives whereas anthocyanins were only detected in maize with partially red pigmented kernels. Major phenolic compounds in the bound phenolic fractions were ferulic acid and its derivatives along with p-coumaric acid. Carotenoid compounds including xanthophylls such as lutein, lutein isomers, and zeaxanthin were only detected in orange and white-yellow pigmented maize and are reported for the first time in Peruvian landraces. The multivariate analysis using Principal Components Analysis (PCA) revealed low variability of all data which may indicate a level of similarity among maize samples based on evaluated variables. However, maize grown in Caylloma province showed more homogeneous physical characteristics and higher yield, whereas higher phenolic contents and antioxidant capacity were observed in maize from Castilla. Samples CAY (yellow-pigmented kernel, Castilla) and COM (orange-pigmented kernel, Caylloma) had the highest total phenolic (246.7 mg/100 g dried weight basis, DW) and carotenoid (1.95 μg/g DW) contents among all samples. The variable Andean environmental conditions along with differences in farming practices may play a role and should be confirmed with further studies. Current results provide the metabolomic basis for future research using integrated omics platforms targeted toward the complete characterization of the ethnic-relevant maize race Cabanita.

Impact of Provenance on Phytochemical Attributes of Pigmented Landrace Maize Varieties

Maize is one of the most diverse cereal crops that contribute highly in calorie supply to human diet. Pigmented maize secondary metabolites which are phytochemicals of healthy importance include carotenoids and phenolics which act as precursors of vitamin A and antioxidants respectively. Pigmented landrace maize is cultivated by smallholder farmers in their localities. Three different pigmented maize varieties from different growing districts were analysed for total carotenoids content (TCC) and total phenolic content (TPC), using spectrophotometer. The districts experience a warm temperate climate and higher rainfall in summer than in winter but they differ in that Ntcheu has highest average annual temperature of 20.3°C while Dedza receives the highest annual precipitation of about 1010 mm. Mzimba has an average annual temperature of 20.1°C and receives about 915 mm of precipitation annually. Individual carotenoids were analysed using high performance liquid chromatography (HPLC). TCC were significantly higher (p < 0.05) in Ntcheu and Mzimba provenances compared to Dedza. Lutein (22.84 ± 1.25 µg/g) and Zeaxanthin (23.16 ± 2.44 µg/g) were highest in landrace orange maize from Ntcheu. Mzimba provenance showed highest beta-cryptoxanthin (8.60 ± 2.15 µg/g). TPC were not significantly different between Dedza (204.29 ± 0.35 mg/Kg) and Mzimba (207.65 ± 0.22 mg /kg) red maize. Ntcheu provenance showed the least TPC (184.06 ± 0.61 mg/Kg). It seems provenance influenced phytochemical attributes of pigmented landrace maize varieties in some instances. This study also revealed that post-harvest handling of pigmented landrace maize affects phytochemical content. Care should, therefore, be taken in handling pigmented landrace maize to avoid phytochemical loses. Farmers and all other stakeholders in Malawi are encouraged to produce and include pigmented landrace maize varieties in their diets in order to gain the associated health benefits. Further studies are needed for complete characterisation of phenolic compounds of pigmented landrace maize of Malawi.

Status of carotenoids in elite and landrace maize genotypes: Implications for provitamin A biofortification in Tanzania

Maize is among the crops containing carotenoids that are easily converted to vitamin A and have an enormous influence on consumers' health. Principally maize has high calories and proteins but has less number of other micronutrients such as vitamin A. Societies that use maize as their main and sole staple food are likely to be affected by vitamin A deficiency. Thus, development and production of maize varieties rich in micronutrients and vitamin A are important for improved health. This study characterized 5 carotenoid components in maize genotypes grown in Tanzania as a strategy for improving vitamin A content in maize. The study involved maize landraces, commercial or elite varieties, and inbred lines in determining their potential for provitamin A breeding programs for nutrition improvement. The study found that mean concentration of important carotenoid components, i.e., alpha carotene (AC), beta-carotene (BC), beta-cryptoxanthin (BCX), lutein (LU), zeaxanthin (ZX), provitamin A (ProVA), non-provitamin A (Non-ProVA), and total carotenoids (TC) varied significantly (P < 0.001) among maize genotypes. The 3 maize groups studied (landraces, commercial varieties, and breeding materials (BMs) varied significantly. For maize landraces, the concentration (µg/g) of studied carotenoids were AC (0.13–2.67), BC (0.60–3.72), BCX (0.36–1.01), ProVA (0.89–5.29), Retinol (0.25–0.87), LU (2.37–16.97). ZX (0.16–4.41), Non-ProVA (2.4–19.01), and TC (3.68–25.27); in commercial or elite maize varieties were (in µg/g): AC (0.31–3.84), BC (0.56–6.5), BCX (0.46–2.58), ProVA (0.92–11.80), Retinol (0.15–1.82), LU (3.28–22.39). ZX (0.05–11.31), Non-ProVA (2.56–28.81), and TC (4.23–37.84); and for maize BMs AC (0.53–6.64), BC (1.92–13.87), BCX (0.65–6.51), ProVA (2.69–18.62), Retinol (0.5–3.1), LU (4.86–34.99), ZX (0.06–18.58), Non-ProVA (4.8–53.57), and TC (9.86–76.94). Furthermore, the study found that the concentration of studied carotenoids was higher in pigmented (yellow or red) maize genotypes than in white maize genotypes. The current study found an appreciable amount of ProVA in studied materials, including maize landraces, commercial yellow varieties, and CIMMYT lines. The concentration of ProVA and retinol determined in studied maize genotypes were below 15 µg/g a daily vitamin A requirement, thus based on the current ProVA and retinol status it is difficult to meet Vitamin A requirement. Therefore, these maize genotypes with promising levels of carotenoid components are potential breeding materials that can be used in maize provitamin A biofortification program for improved food nutrition and livelihoods in Tanzania.

Characterization of Provitamin A Status and Distribution in Commercial Grown Maize Varieties in Tanzania

Provitamin A carotenoids are important as precursors for vitamin A, essential for stronger immune system and eyesight. Consumption of a plant-based diet rich in provitamin A such as provitamin A maize is an easy and affordable source of vitamin A. The majority of the commercially grown maize varieties in Tanzania are white whose provitamin A status is uncertain and undocumented. The existing current information suggests that white maize varieties have low provitamin A, an active form of vitamin A, thus putting maize consumers at risk of vitamin A deficiency (VAD). Characterization of provitamin A status in commercial maize varieties grown and consumed in Tanzania is important to provide baseline information required for vitamin A rich-maize improvement programs. Therefore, this study was conducted to map the status of provitamin A in commercial maize varieties to accrue the information needed to improve maize nutrition quality toward controlling VAD in the country. The study involved 14 maize varieties including commercial yellow and white pigmented maize from 3 regions of Tanzania. From maize samples, carotenoid extraction was conducted based on a protocol adapted from Kurilich and Juvik (1999). The concentration of beta carotene (BC), beta-cryptoxanthin (BCX), alpha-carotene (AC) were determined by an ultraviolet spectrophotometer and provitamin A computed for the individual carotenoids components. The study found that the concentration of provitamin A and associated carotenoids significantly differed (p&lt;0.001) among varieties studied. The mean concentration (in μg/g) for provitamin A and its components in range as provitamin A (2.64-6.50), BC (1.91-4.66), BCX (0.649-1.21), and AC (0.819-1.46). The concentrations of provitamin A in the studied maize varieties were below the recommended levels (15 μg/g). The low concentrations of provitamin A among commercial maize varieties signify the

Influence of thermal treatment on Anthocyanin, total phenolic content and antioxidant capacity of Pigmented Maize (Zea mays L.)

Pigmented maize (Zea mays L.) is a healthy crop due to its perfect proximates and phytochemicals. Thermal treatment was widely used to enhance phytochemical constituents in different kinds of crops. This research evaluated the impact of temperature (100, 115, 130 °C) and duration (10, 15, 20 min) in roasting to anthocyanin, total phenolic content and antioxidant capacity of pigmented maize. Results showed that thermal treatment at 115 °C in 10 min significantly improved anthocyanin in pigmented maize; however, this content would be lower at higher temperatures or prolonged exposing time. Meanwhile, total phenolic content and antioxidant capacity in the pigmented maize were recorded at the highest level when being roasted at 100 oC for 10 min. This research proved that phytochemical constituents and antioxidant capacity inside the pigmented maize would be seriously damaged at high temperatures and extended duration in roasting. By this, producers should pay more attention to thermal conditions in roasting.

Optimization of lipophilic compounds in tortillas from native pigmented maize elaborated by the lime cooking extrusion process

The lime-cooking extrusion process depicts emerging technologies to making maize tortillas with the advantages of reducing energy, little water use, and not environmental deletions effluents. Multi-response optimization by response surface methodology (RSM) was a tool to optimize native pigmented maize lime-cooking extrusion process to obtain flours to develop tortillas with high lipophilic compounds. The effects of extrusion temperature (ET, 65–135 ºC) and screw speed (SS, 78–212 rpm) were investigated. The best extruded blue maize tortillas were selected over response variables: Linoleic acid (LA), Oleic acid (OA), Campesterol (CP), Stigmasterol (SP), and b-sitosterol (bSP), where the quadratic predictive developed models were adequate and reproducible inside the specified array of process factors. Appling desirability function, the optimum lime-cooking extrusion conditions to development extruded blue maize tortillas correspond to ET (119 °C), SS (78 rpm) and a global desirability value (D = 0.906). Values response variables obtained from the predictive models were compared from experimental tests, a close agreement between both values was observed. Hence, RSM is still convenient for optimization, particularly once used in mixture with other procedures.

Nutritional properties and phenolic acid profile of selected Philippine pigmented maize with high antioxidant activity

Ten (10) accessions of pigmented maize collected from the various regions in the Philippines with the highest antioxidant activity were evaluated for several chemical and nutritional parameters such as proximate composition, carbohydrate profile (starch, amylose and amylopectin contents), phenolic acid, mineral (iron and zinc) and food energy contents. Ranges of proximate components were as follows: fat, 4.14–5.67 %; protein, 9.28–15.87 %; fiber, 1.30–3.84 %; ash, 1.22–1.62 %; and nitrogen free extract, 71.30–77.75 %. Significant variations were observed in fat and protein contents, and nitrogen free extract. Coumaric, ferulic, and gallic acids were the major phenolic acids identified to be present in the pigmented corn kernels using HPLC. Amylose and amylopectin contents ranged from 23.53 to 28.96% and 16.68–45.18 %, respectively. On the other hand, total starch content ranged from 44.32 to 72.44 % while food energy content registered 246.74–369.16 Kcal 100 g−1 DW. Iron and zinc concentrations were quantified using AAS, iron content ranged from 53.06 to 77.96 mg kg−1 while 48.64–64.08 mg kg−1 of zinc content was recorded. Only zinc concentration of the selected maize accessions was found to be significantly different among accessions. This study provides baseline information on the nutritional value of pigmented maize accessions in the Philippines which can be used for future breeding works and enhance germplasm utilization focused on improved nutritional and functional properties of Philippine corn for health and wellness.

Comparison of total polyphenols, profile anthocyanins, color analysis, carotenoids and tocols in pigmented maize

Total phenolics, flavonoids, anthocyanins, CIELAB color, tocols and carotenoids were determined in whole kernels of four different pigmented (yellow, red, blue and purple) maize genotypes. The aim of this work was devoted i) to characterize the anthocyanin profile, ii) to compare the bioactive phytochemical substances, iii) to promote the introduction of new pigmented maize genotypes. Anthocyanins detected were mainly eight: cyanidin, petunidin, pelargonidin and peonidin-3-glucoside and their malonated derivatives. Acylated anthocyanins were far more abundant than glycosilated anthocyanins. Among the pigmented maize samples, the purple kernel genotype showed the highest concentration of anthocyanins. Color analysis of individual kernels of the four maize samples showed difference between the average L*a*b* values, detecting high correlations between L*, C* and Hue. Anthocyanins were negatively significantly correlated versus L*, C* and Hue. Considerable differences in phytochemical contents were observed between the genotypes. Principal Component Analysis provided a good summary of the results; it accounted for about 91% of total variance and clearly discriminated the four genotypes based on their specific chemical composition. Purple kernel maize genotype showed a higher content of total phenolics, flavonoids, proanthocyanidin, whereas yellow maize showed higher content in carotenoids and red maize resulted dominant in total tocols.

Consumption of nixtamal from a new variety of hybrid blue maize ameliorates liver oxidative stress and inflammation in a high-fat diet rat model

Abstract Continuous consumption of functional foods rich in antioxidants leads to several health benefits on non-communicable diseases. Pigmented maize, a traditional Mexican food, contains a high quantity of antioxidants. We determined the phytochemical composition of a raw and alkaline treated (nixtamal) blue hybrid maize (Zea mays L. var. E3E4) and investigated the effect of the nixtamal consumption on the liver oxidative stress and inflammation on rats fed a high-fat diet. We fed Wistar rats for eight weeks with standard diet, HFD, and HFD + Nixtamal. The nixtamalization process modified the chemical profile being cyanidin-3-O-glucoside the main anthocyanin compound (92.19%). Antioxidant capacity by ABTS (IC50 668.70 μg/mL) was increased. Sod1 gene expression and total liver antioxidant capacity were augmented after nixtamal treatment while MDA levels decreased. Histological analysis revealed a statistical reduced liver inflammation. Finally, our data suggest that maize’s anthocyanins counteract directly liver ROS, increasing Sod1, and ameliorate liver damage.

Pigmented maize - a potential source of β-carotene and α-tocopherol

&amp;lt;p&amp;gt;Among cereals, maize has the highest content of bioavailable micronutrients in grain, particularly &amp;amp;beta;-carotene and &amp;amp;alpha;-tocopherol, which makes this crop the most appropriate for biofortification. Great genetic variability is a valuable source of micronutrients, and genotypes with enhanced grain content could be used for improvement of commercial hybrids or synthetic populations creation. Three populations with dark orange, dark red and red grain, five elite lines, and their crosses were evaluated for &amp;amp;beta;-carotene and &amp;amp;alpha;-tocopherol content. Based on obtained results, line (L5) could be further used in breeding for increased &amp;amp;beta;-carotene content, and population with dark orange grain (P1) is recommended as a good source for multi-nutrient biofortification for both &amp;amp;beta;-carotene and &amp;amp;alpha;-tocopherol. Three lines (L1, L2 and L5) had significantly higher value of &amp;amp;alpha;-tocopherol in crosses with dark red population (P2), compared to lines per se, and require several cycles of back-crossing for increase nutrient content.&amp;lt;/p&amp;gt;

Phenolic Profile and Susceptibility to Fusarium Infection of Pigmented Maize Cultivars.

Maize is a staple food source in the world, whose ancient varieties or landraces are receiving a growing attention. In this work, two Italian maize cultivars with pigmented kernels and one inbred line were investigated for untargeted phenolic profile, in vitro antioxidant capacity and resistance to Fusarium verticillioides infection. “Rostrato Rosso” was the richest in anthocyanins whilst phenolic acids were the second class in abundance, with comparable values detected between cultivars. Tyrosol equivalents were also the highest in “Rostrato Rosso” (822.4 mg kg−1). Coherently, “Rostrato Rosso” was highly resistant to fungal penetration and diffusion. These preliminary findings might help in breeding programs, aiming to develop maize lines more resistant to infections and with improved nutraceutical value.

Effect of dietary polyphenols on the in vitro starch digestibility of pigmented maize varieties under cooking conditions

Interest in using polyphenols as modulators of the activity of starch digestive enzymes is increasing. The main purpose of this study was to investigate the role of phenolic compounds characterising pigmented maize flours in the modulation of in vitro starch digestibility. Flours from three different pigmented maize varieties were evaluated under cooking conditions and compared to common yellow maize (YM). The untargeted metabolomics-based approach comprehensively annotated around 300 phenolic compounds, with a high distribution of anthocyanins and phenolic acids (in free and bound fractions of maize samples) and significant differences across genotypes. Following in vitro starch digestion, the cooked pigmented maize flours showed higher resistant starch content (from 5.1 to 6.9 g /100 g dry matter), as well as lower starch hydrolysis index (HI) when compared to YM flour, with the “Rostrato Rosso” maize having the lowest HI (i.e., 61). Coherently, multivariate statistics following metabolomics showed the discrimination potential of anthocyanins' profile after cooking, characterising the “Rostrato Rosso” during in vitro digestion. These findings might be related to the modulation of enzyme activity by phenolic compounds during in vitro digestion. Therefore, the use of pigmented maize flours might help in the formulation of gluten-free foods with slowly digestible starches by exploiting the wide phenolic composition of these matrices.

CUANTIFICACIÓN DE ANTOCIANINAS MEDIANTE ESPECTROSCOPÍA DE INFRARROJO CERCANO Y CROMATOGRAFÍA LÍQUIDA EN MAÍCES PIGMENTADOS

El método de espectroscopia de infrarrojo cercano se utiliza ampliamente para la determinación de ciertos compuestos químicos. Actualmente es una herramienta de soporte para los programas de mejoramiento, que permite la determinación de compuestos como proteína, almidón, aceite, humedad y cenizas, entre otros. Un total de 554 muestras pertenecientes a 24 razas de maíz (Zea mays L.) pigmentado fueron utilizadas en el desarrollo y validación de modelos matemáticos para la estimación del contenido de antocianinas por espectroscopía de infrarrojo cercano (NIR), a través de la espectroscopía de UV-Vis como método de referencia. Se determinó el perfil de antocianinas mediante cromatografía líquida de alta resolución (HPLC). Los más altos contenidos de antocianinas se encontraron en muestras de grano de maíz C11-IXT de Tlaxcala, México, con hasta 1989.9 μg Pel g-1 PS. Los mayores porcentajes de cianidina 3-glucósido, pelargonidina 3-glucósido y peonidina 3-glucósido fueron 48.79 %, 39.84 % y 12.14 %, respectivamente. Muestras de la accesión BOZM342 destacaron por el contenido de cianidina 3-glucósido, que fue de 628.32 μg g-1 PS. Se desarrollaron y analizaron 32 modelos de calibración de los cuales destacaron dos por cumplir los parámetros para una calibración de NIR robusta, con altos coeficientes de determinación para las validaciones cruzadas (0.64 y 0.65). Los modelos de NIR presentados en este trabajo se pueden utilizar para la determinación de antocianinas totales y apoyar a los programas de mejoramiento de maíces azules.

Survey of Anthocyanin Composition and Concentration in Diverse Maize Germplasms.

Increasing consumer demand for natural ingredients in foods and beverages justifies investigations into more economic sources of natural colorants. In this study, 398 genetically diverse pigmented accessions of maize were analyzed using HPLC to characterize the diversity of anthocyanin composition and concentration in maize germplasm. One hundred and sixty-seven accessions were identified that could produce anthocyanins in the kernel pericarp or aleurone and were classified into compositional categories. Anthocyanin content was highest in pericarp-pigmented accessions with flavanol-anthocyanin condensed forms, similar to the Andean Maı́z Morado landraces. A selected subset of accessions exhibited high broad-sense heritability estimates for anthocyanin production, indicating this trait can be manipulated through breeding. This study represents the most comprehensive screening of pigmented maize lines to date and will provide information to plant breeders looking to develop anthocyanin-rich maize hybrids as an economic source of natural colorants in foods and beverages.

Use of Pigmented Maize in Both Conventional Dry‐Grind and Modified Processes Using Granular Starch Hydrolyzing Enzyme

In the dry‐grind ethanol process, distillers dried grains with solubles (DDGS) is the main coproduct, which is primarily used as an ingredient in ruminant animal diets. Increasing the value of DDGS will improve the profitability of the dry‐grind ethanol process. One way to increase DDGS value is to use pigmented maize as the feedstock for ethanol production. Pigmented maize is rich in anthocyanin content, and the anthocyanin imparts red, blue, and purple color to the grain. It is reported that anthocyanin would be absorbed by yeast cell walls during the fermentation process. The effects of anthocyanin on fermentation characteristics in the dry‐grind process are not known. In this study, the effects of anthocyanin in conventional (conventional starch hydrolyzing enzymes) and modified (granular starch hydrolyzing enzymes [GSHE]) dry‐grind processes were evaluated. The modified process using GSHE replaced high‐temperature liquefaction. The ethanol conversion efficiencies of pigmented maize were comparable to that of yellow dent corn in both conventional (78.4 ± 0.5% for blue maize, 74.3 ± 0.4% for red maize, 81.2 ± 1.0% for purple maize, and 75.1 ± 0.2% for yellow dent corn) and modified dry‐grind processes using GSHE (83.8 ± 0.8% for blue maize, 81.1 ± 0.3% for red maize, 93.5 ± 0.8% for purple maize, and 85.6 ± 0.1% for yellow dent corn). Total anthocyanin content in DDGS from the modified process was 1.4, 1.9, and 2.4 times of that from the conventional process for purple, red, and blue maize samples, respectively. These results indicated that pigmented maize rich in anthocyanin did not negatively affect the fermentation characteristics of the dry‐grind process and that there was a potential to use pigmented maize in the dry‐grind process, especially when using GSHE.