Chemical composition and physical properties of sorghum flour prepared from different sorghum hybrids grown in Argentina

This work analyzed the physical, chemical, and thermal properties of sorghum flour and the relationships among these, in order to evaluate its suitability for the development of food products. Sorghum flour was obtained through roller dry milling from 20 commercial hybrids grown in Argentina with the average chemical composition of the samples being: 0.68% ash, 3.67% fat, 12.21% protein, 83.45% total carbohydrates, 79.77% starch (amylose 26.6%), and 34.9 mg of tannic acid per 100 g of flour. A high degree of variability among evaluated properties was found, particularly in the pasting properties peak viscosity (2809–5184 mPa/s), breakdown (1169–3170 mPa/s), and final viscosity (3030–4401 mPa/s) with onset temperature (To) and gelatinization enthalpy (ΔH) varying between 66.8 and 72.6°C, and 5.38 and 8.48 J/g, respectively. A principal component analysis demonstrated that the grain color did not influence the chemical composition of the flour. Cluster analysis permitted the separation of flour into three different groups with different thermal and physicochemical characteristics, and enabled the selection of hybrids. Thus, sorghum flour is a versatile ingredient and can be used in several food and non-food applications.Fil: Palavecino, Pablo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Penci, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Calderón-Domínguez, Georgina. Instituto Politécnico Nacional; MéxicoFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

Starch Biodegradable Films Produced by Electrospraying

The use of particles obtained from biopolymers is of interest in fields such as bioengineering and nanotechnology, with applications in drug encapsulation, tissue engineering, and edible biofilms. A method used to obtain these particles is electrohydrodynamic atomization (EHDA), which can generate different structures depending on the process conditions and raw materials used, opening a wide range of research in the biopolymers field, where starch is considered an excellent material to produce edible and biodegradable films. This chapter is a compilation and analysis of the newest studies of this technique, using starch with or without modifications to prepare films or membranes and their potential applications. A systematic literature review, focused on starch, and EHDA was carried out, finding 158 articles that match these criteria. From these results, a search inside them, using the words edible and biodegradable was conducted, showing 93 articles with these key words. The information was analyzed observing the preference to use corn, potato, rice, and cassava starches, obtaining mainly scaffolds and fibers and, in much less proportion, films or capsules. This review shows a window of opportunity for the study of starchy materials by EHDA to produce films, coatings, and capsules at micro or nano levels

Acondicionamiento de garbanzo (Cicer arientium) por el proceso de nixtamalización para la obtención de harina utilizada en la elaboración de pan de caja

Objective: The aim was to establish the effect on quality characteristics of loaf bread added with chickpea flour obtained by nixtamalization and soaking processes. Design/methodology/approach: The nixtamalization process was realized using 2% Ca(OH)2 solution, 3:1 (w/v) with respect to the grain, and cooking for 80 min. After 14 h, the nixtamal was washing three times. Nixtamalized grains were dried, milled and sieved (U.S. 35 mesh). The flour obtained by the soaking method (12 h, T=21 °C), was cooked (95 °C, 45 min), drying (48 h, 48 °C) and milling. The characterization of colour and ashes was determined on the flour and bread, also physical, quality and sensorial characteristics were measured. Results: The results demonstrated that substitution with 35% of nixtamalized chickpea flour, showed the best quality on physical and nutritional characteristics according with the reference (hardness: 23.6 ± 3 and 20.8 ± 6.2 N, color (C): 28.4 ± 1.37 and 29.2 ± 0.927, ashes: 0.17 and 1.43%, respectively). Limitations on study/implications: Results of sensory analysis of bread obtained by the soaking method has shown that the colour and flavour characteristics were not desired. Findings/conclusions: The information obtained demonstrates that this process has a positive impact for the consumer, increasing the availability of some nutrients.Objetivo: Establecer el efecto en las características de calidad de pan de caja elaborado con harina de garbanzo (Cicer arientium L.) obtenida por nixtamalización y remojo. Diseño/metodología/aproximación: El proceso de nixtamalización se realizó utilizando una solución de Ca(OH)2 al 2% en una relación 3:1 (p/v) con respecto al grano, se coció durante 80 min. Después de 14 h, el nixtamal se lavó tres veces. Los granos nixtamalizados se secaron, molieron y tamizaron (U.S. 35 mesh). Para el método de remojo (12 h, T = 21 ° C), el garbanzo se coció (95 °C, 45 min), se secó (48 h, 48 ° C) y se molió. Se determinó el color y cenizas en la harina y el pan, también se midieron las características físicas, de calidad y señoriales de este último. Resultados: Los resultados mostraron que el pan sustituido con 35% de harina de garbanzo nixtamalizado, presentó las mejores características de calidad, físicas y nutrimentales con respecto al testigo (dureza: 23.6±3 y 20.8±6.2 N, color (C): 28.41±1.368 y 29.23±0.927, cenizas: 0.17 y 1.43% respectivamente). Limitaciones del estudio/implicaciones: La evaluación sensorial del pan elaborado con harina de garbanzo obtenida por remojo indicó que estos presentaban sabor más intenso así como color no característico, que desagrado a los jueces. Hallazgos/conclusiones: Los resultados tienen un impacto positivo para el consumidor, incrementando la disponibilidad de algunos nutrientes

Actividad antihipertensiva de péptidos de zeína extraídos de maíz (Zea mays L.) criollo (azul y rojo) del Estado de México

Objective: To evaluate the antihypertensive activity of peptides extracted from nixtamalized and non-nixtamalized creole corn (blue and red) zein from the Estado de México. Design / methodology / approach: Bioinformatic tools, such as the NCBI database, were used to search for primary sequences of the maize zein protein. The methodology included a prediction of peptides with antihypertensive activity through various bioinformatic servers. Inhibitory activity was determined by percentage regression. Statistical analysis was performed to assess possible significant differences using the Tukey test (p <0.05). Results: The following peptides were found by in silico hydrolysis: IFSILMLLA, LSACVLDATI, TASVCENPTL, LPLSPLLFQQ, SPALSLVQSL, LSPYSQQQQF, PFSQLATAY, LPFYQQFSAN and PAAFYQQHII that showed inhibition activity. The results showed that the GH (grade of hydrolysis) was higher in blue corn (13.96 ± 0.02) than in red corn (10.38 ± 0.79) without nixtamalization, while, with the nixtamalization process, this parameter was also higher in blue corn (10.52 ± 0.57) than in red corn (8.96 ± 0.01). Study limitations / implications: The enzyme used for hydrolysis generates oligopeptides that may not be as closely related to the angiotensin-converting enzyme. Findings / Conclusions: In vitro antihypertensive activity of unhydrolyzed blue corn zein showed a lower percentage of ACE inhibition compared to unhydrolyzed red corn. Trypsin hydrolysis only increases ACE inhibitory activity in blue corn at a concentration of 0.3 mg / mL without nixtamalizing.Objetivo: Evaluar la actividad antihipertensiva de péptidos extraídos de zeína de maíz criollo azul y rojo nixtamalizado y sin nixtamalizar del Estado de México. Diseño/metodología/aproximación: Se emplearon herramientas bioinformáticas, tales como la base de datos NCBI para la búsqueda de secuencias primarias de la proteína zeína del maíz. La metodología incluyó una predicción de los péptidos con actividad antihipertensiva a través de diversos servidores bioinformáticos. La actividad inhibitoria se determinó mediante la regresión del porcentaje. Se realizó un análisis estadístico para evaluar las posibles diferencias significativas utilizando la prueba de Tukey (p<0.05). Resultados: Por medio de la hidrólisis in sílico se encontraron los siguientes péptidos: IFSILMLLA, LSACVLDATI, TASVCENPTL, LPLSPLLFQQ, SPALSLVQSL, LSPYSQQQQF, PFSQLATAY,            LPFYQQFSAN y PAAFYQQHII que mostraron actividad de inhibición de la ECA. Los resultados mostraron que el GH de la zeína fue mayor en maíz azul (13.96±0.02) que en maíz rojo (10.38±0.79) sin nixtamalizar, mientras que, con el proceso de nixtamalización, este parámetro también fue mayor en el maíz azul (10.52±0.57) que en el maíz rojo (8.96±0.01). Limitaciones del estudio/implicaciones: La enzima utilizada para la hidrólisis enzimática genera oligopéptidos que tal vez no puedan ser tan afines a la enzima convertidora de angiotensina. Hallazgos/conclusiones: La actividad antihipertensiva in vitro del maíz azul sin hidrolizar mostraron un menor porcentaje de inhibición de la ECA con respecto al maíz rojo sin hidrolizar. La hidrólisis con tripsina solo incrementa la actividad inhibitoria de la ECA en maíz azul a concentración de 0.3 mg/mL sin nixtamalizar

Nano- and micro-mechanical properties of wheat grain by atomic force microscopy (AFM) and nano-indentation (IIT) and their relationship with the mechanical properties evaluated by uniaxial compression test

The mechanical properties of hard and soft wheat cultivars at different structural-levels were evaluated at 10% and 15% moisture content by AFM, IIT and compression test. Nano and micro-indentation tests revealed that outer-pericarp cells of soft cultivar were stiffer than hard cultivar at 10% moisture. Bran-layers stiffness was reduced as a consequence of higher moisture levels in both cultivars. Additionally, endosperm hardness and stiffness were similar in both cultivars at 10% moisture, although soft-wheat endosperm was softer and less stiff than hard wheat at 15% moisture. Regarding compression test, soft cultivar showed lower fracture force than hard cultivar at the same moisture level. Moreover, stiffness, fracture force and deformation were reduced by higher moisture levels in both cultivars. The relationship between the nano-, micro- and macro-mechanical properties of wheat kernels indicated that soft cultivar at 10% and 15% was associated with stiffer outer-pericarp cells and higher fracture deformation, respectively. However, hard cultivar at 10% and 15% was related to higher endosperm hardness and fracture force and higher bran layers hardness, respectively.Fil: Barrera, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Físicas, Exactas y Naturales (FCFEYN). Instituto de Ciencia y Tecnología de Alimentos Córdoba (ICYTAC); ArgentinaFil: Méndez-Méndez, Juan. Instituto Politécnico Nacional. Centro de Nanociencias y Micro y Nanotecnologías; MéxicoFil: Arzate-Vázquez, Israel. Instituto Politécnico Nacional. Centro de Nanociencias y Micro y Nanotecnologías; MéxicoFil: Calderón-Domínguez, Georgina. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Físicas, Exactas y Naturales (FCFEYN). Instituto de Ciencia y Tecnología de Alimentos Córdoba (ICYTAC); Argentin

Evaluation of the mechanical damage on wheat starch granules by SEM, ESEM, AFM and texture image analysis

The effect of mechanical damage on wheat starch granules surface, at a microstructural level, was investigated by scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), atomic force microscopy (AFM), and image textural analysis. The SEM and ESEM images of the native sample showed that the starch granules had smooth, flat surfaces and smooth edges. The samples with higher damaged starch content exhibited granular distortion, irregularity and less uniformity. The fractal dimension of contour parameter increased with mechanical damage, indicating thatthe surface irregularities quantitatively increased due to the damage. The surfaces of damaged granules showed depressions of different shapes and sizes. The roughness parameters and fractal dimension of the surface increased as a result of the mechanical damage. The surface of damaged granules showed higher entropy and lower homogeneity values when damaged starch increased. The results indicated that the mechanical process caused structural modifications at nano level.Fil: Barrera, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Calderón Domínguez, Georgina. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Chanona Pérez, Jorge. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Gutiérrez López, Gustavo F.. Instituto Politécnico Nacional. Escuela Nacional de Ciencias Biológicas; MéxicoFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Nacional de Córdoba. Secretaría de Ciencia y Tecnología. Instituto Superior de Investigación, Desarrollo y Servicio de Alimentos; Argentin

Modified Starch-Chitosan Edible Films: Physicochemical and Mechanical Characterization

Starch and chitosan are widely used for preparation of edible films that are of great interest in food preservation. This work was aimed to analyze the relationship between structural and physical properties of edible films based on a mixture of chitosan and modified starches. In addition, films were tested for antimicrobial activity against Listeria innocua. Films were prepared by the casting method using chitosan (CT), waxy (WS), oxidized (OS) and acetylated (AS) corn starches and their mixtures. The CT-starches films showed improved barrier and mechanical properties as compared with those made from individual components, CT-OS film presented the lowest thickness (74 ± 7 µm), water content (11.53% ± 0.85%, w/w), solubility (26.77% ± 1.40%, w/v) and water vapor permeability ((1.18 ± 0.48) × 10−9 g·s−1·m−1·Pa−1). This film showed low hardness (2.30 ± 0.19 MPa), low surface roughness (Rq = 3.20 ± 0.41 nm) and was the most elastic (Young’s modulus = 0.11 ± 0.06 GPa). In addition, films made from CT-starches mixtures reduced CT antimicrobial activity against L. innocua, depending on the type of modified starch. This was attributed to interactions between acetyl groups of AS with the carbonyl and amino groups of CT, leaving CT with less positive charge. Interaction of the pyranose ring of OS with CT led to increased OH groups that upon interaction with amino groups, decreased the positive charge of CT, and this effect is responsible for the reduced antimicrobial activity. It was found that the type of starch modification influenced interactions with chitosan, leading to different films properties

Modified Starch-Chitosan Edible Films: Physicochemical and Mechanical Characterization

Starch and chitosan are widely used for preparation of edible films that are of great interest in food preservation. This work was aimed to analyze the relationship between structural and physical properties of edible films based on a mixture of chitosan and modified starches. In addition, films were tested for antimicrobial activity against Listeria innocua. Films were prepared by the casting method using chitosan (CT), waxy (WS), oxidized (OS) and acetylated (AS) corn starches and their mixtures. The CT-starches films showed improved barrier and mechanical properties as compared with those made from individual components, CT-OS film presented the lowest thickness (74 ± 7 µm), water content (11.53% ± 0.85%, w/w), solubility (26.77% ± 1.40%, w/v) and water vapor permeability ((1.18 ± 0.48) × 10−9 g·s−1·m−1·Pa−1). This film showed low hardness (2.30 ± 0.19 MPa), low surface roughness (Rq = 3.20 ± 0.41 nm) and was the most elastic (Young’s modulus = 0.11 ± 0.06 GPa). In addition, films made from CT-starches mixtures reduced CT antimicrobial activity against L. innocua, depending on the type of modified starch. This was attributed to interactions between acetyl groups of AS with the carbonyl and amino groups of CT, leaving CT with less positive charge. Interaction of the pyranose ring of OS with CT led to increased OH groups that upon interaction with amino groups, decreased the positive charge of CT, and this effect is responsible for the reduced antimicrobial activity. It was found that the type of starch modification influenced interactions with chitosan, leading to different films properties

Sponge cake microstructure, starch retrogradation and quality changes during frozen storage

The effect of frozen storage (6 months) on the microstructure (microscopy, flatbed scanning and image analysis), quality (texture, moisture and specific volume) and starch retrogradation of the cake crumb were evaluated. After 2 months of storage, texture (firmness, cohesiveness and resilience) was significantly (P < 0.05) affected and starch retrogradation was observed, while by the fourth month, the crystallinity increased and crumb fractures were noticeable. Additionally, the shrinkage of starch granules was observed as the starch circularity (Sc) values significantly decreased (P < 0.05) by the sixth month of storage. Although structural changes were not detected by image analysis, it was demonstrated that cake microstructure damage is related to physical changes because the Sc was significantly correlated (P < 0.05) with moisture and specific volume and therefore with the cake quality and texture. Moreover, sugar re-crystallisation occurred during frozen storage, and it was significantly correlated (P < 0.05) with the deterioration in cake quality.Fil: Díaz-Ramírez, Mayra. Universidad Autónoma Metropolitana; MéxicoFil: Calderón-Domínguez, Georgina. Instituto Politécnico Nacional; MéxicoFil: Salgado-Cruz, María de la Paz. Consejo Nacional de Ciencia y Tecnología; MéxicoFil: Chanona-Pérez, José J.. Instituto Politécnico Nacional; MéxicoFil: Andraca-Adame, José A.. Instituto Politécnico Nacional; MéxicoFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentin