Scielo RSS <![CDATA[Archivos Latinoamericanos de Nutrición]]> http://ve.scielo.org/rss.php?pid=0004-062220090004&lang=es vol. 59 num. 4 lang. es <![CDATA[SciELO Logo]]> http://ve.scielo.org/img/en/fbpelogp.gif http://ve.scielo.org <![CDATA[<b>Aplicación del modelo de Thurstone a las pruebas sensoriales de diferencia</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400001&lng=es&nrm=iso&tlng=es En las pruebas de diferencia, el desempeño de los jueces varía en función de la prueba utilizada. Esta diferencia se explica a partir del conocimiento sobre la forma en que el cerebro procesa la información que recibe de los sentidos, particularmente el sentido del gusto. En algunas pruebas de diferencia, la información se procesa de manera más eficiente que en otras. El modelo de Thurstone describe las estrategias del cerebro para procesar la información en función del método utilizado. Esta revisión introduce las ideas y los conceptos de este modelo en las mediciones sensoriales derivadas con las pruebas de diferencia. Los conceptos de la variabilidad del estímulo y la estrategia cognitiva correspondiente a cada método de diferencia son la base para el cálculo de la magnitud de la diferencia percibida entre dos estímulos, denominada d’. Esta medición es fundamental e independiente de la metodología sensorial utilizada.<hr/>Part of understanding why judges perform better on some difference tests than others requires an understanding of how information coming from the mouth to the brain is processed. For some tests it is processed more efficiently than others. This is described by what has been called Thurstonian modeling. This brief review introduces the concepts and ideas involved in Thurstonian modeling as applied to sensory difference measurement. It summarizes the literature concerned with the theorizing and confirmation of Thurstonian models. It introduces the important concept of stimulus variability and the fundamental measure of sensory difference: d’. It indicates how the paradox of discriminatory non-discriminators, which had puzzled researchers for years, can be simply explained using the model. It considers how memory effects and the complex interactions in the mouth can reduce d’ by increasing the variance of sensory distributions. <![CDATA[<b>Revisión del papel de los oligosacáridos prebióticos en la prevención de infecciones gastrointestinales</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400002&lng=es&nrm=iso&tlng=es Las enfermedades gastrointestinales siguen siendo un problema de salud pública mundial. El avance de la ciencia muestra que cambios en el balance adecuado de la microflora intestinal (MI) juegan un papel crucial en la patogénesis. La evidencia apunta a que una manera de modular esta MI es a través del uso de oligosacáridos prebióticos, que estimulan el crecimiento de bacterias benéficas y que a la vez aumentan la resistencia a la invasión por patógenos. Estudios con animales indican que el consumo de carbohidratos prebióticos podría estar implicado en la prevención y tratamiento de diarreas. En infantes humanos sanos, los estudios revelan que el consumo de mezclas de prebióticas (galactooligosacáridos/fructooligosacáridos, inulina/galactooligosacáridos) disminuyen la incidencia de fiebre, de infecciones y de patógenos gastrointestinales. Lo anterior representa un gran potencial para los alimentos funcionales que los contienen, principalmente las fórmulas infantiles. Sin embargo, los estudios de prevención de diarreas mediante el suministro de prebióticos en personas con una microflora intestinal alterada no son concluyentes, sobre todo aquellos practicados en ancianos, personas con problemas crónicos de inflamación intestinal y personas con diarreas asociadas a la toma de antibióticos. Lo anterior nos indica la necesidad de estudios bioquímicos y microbiológicos más profundos en humanos de diferentes edades y condiciones de salud intestinal, a fin de determinar en que condiciones, los prebióticos tienen algún efecto sobre las infecciones.<hr/>Gastrointestinal disorders are still a main world public health problem. Scientific progress shows that and inadequate balance in intestinal microbiota (IM) plays a crucial role in its pathogenesis. Evidence indicates that one way to modulate the IM is through the use of prebiotics. These oligosaccharides stimulate the growth of benefic bacteria and increase the resistance to invading pathogens. Research using animals show that the consumption of prebiotics could be implicated in prevention and treatment of diarrhea. Studies in healthy infants also indicate that the consumption of prebiotic mixtures (galactooligosaccharides/ fructooligosaccharides, inulin/ galactooligosaccharides) decreases the incidence of fever, infections and pathogens. These results represent a great potential for functional foods that contain prebiotics, mainly the infant formulas. However, results of other clinical studies for prebiotics effects on diarrhea are not conclusive. Specially those studies that include patients with an altered IM (like the elderly), patients with chronic intestinal inflammation and with diarrhea associated to antibiotic treatments. There is a need for more biochemical and microbiological studies in humans at different ages and intestinal health conditions, in order to determine when prebiotics may effectively function on infections. <![CDATA[<b>Peso de nacimiento y posterior estado nutricional, desarrollo cognitivo y actividad ocupacional</b>: <b>una revisión crítica</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400003&lng=es&nrm=iso&tlng=es El impacto del estado nutricional prenatal, especialmente lo concerniente al peso de nacimiento (PN) y sus efectos tanto en el corto, mediano o largo plazo, sobre el estado nutricional y el desarrollo cognitivo del niño y, sobre la ocupación desempeñada en la vida adulta, ha sido una problemática de interés para diversos investigadores; al respecto, algunos autores encuentran una asociación positiva y significativa entre estas variables, mientras que otros no encuentran ninguna relación. Es así como se ha descrito que niños con PN insuficiente, bajo o, extremadamente bajo, además del deterioro temprano del estado nutricional, presentarían en el corto plazo, un mayor riesgo de daño en la maduración cerebral, retraso del desarrollo cognitivo y menores circunferencias craneanas, lo que implicaría menor volumen encefálico y bajo rendimiento intelectual. En el corto y mediano plazo, esta situación perjudicaría el proceso enseñanza-aprendizaje en la etapa escolar, mientras que en el largo plazo, esto condicionaría la ocupación a desempeñar en la vida adulta. Actualmente, el cuerpo de conocimientos pone de manifiesto que los hallazgos relativos a estas asociaciones no son concluyentes, existiendo gran controversia en estas materias. Este artículo de revisión tiene el propósito de analizar la evidencia existente hasta este momento, con el objeto de incentivar la investigación en estos aspectos que son de gran relevancia para el desarrollo del niño y su vida futura.<hr/>The impact of prenatal nutritional status, assessed through birth weight (BW) and their effects in the short, medium and long-term on nutritional status, cognitive development and job status in the adult life, has been a problem of interest for several researchers; as regards, some of these report a positive and significant association between these variables and others do not find any relation. Children with insufficient, low or very low BW despite the early more deteriorate nutritional status should present higher risk for brain maturation, failure cognitive development and lowered head circumference which implies both lowered brain volume and intellectual development. In the short and medium-term, this situation damages the learning process at school-age, while in the long-term this might condition the quality of jobs. At present, the body of knowledge pinpoints that findings related to these associations is not conclusive verifying a great controversy in these matters. This review article has the purpose of analyzing the current evidence, in order to stimulate research about to these aspects which are relevant for child development and their future life. <![CDATA[<b>Un enfoque para un problema sanitario y social</b>: <b>yodurias en embarazadas de una región yododeficiente</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400004&lng=es&nrm=iso&tlng=es La yoduria o eliminación urinaria de yodo (EUI) es un método efectivo para detectar el déficit en su ingesta. En 121 embarazadas se midió yoduria en dos muestras (matutina y vespertina) con el método turbidimétrico modificado por Pino. Se consideró normal una EUI =150 ug/l. En las mujeres con EUI<100ug/l se investigó la función tiroidea. De 121 embarazadas la yoduria fue normal en 75, en las que la yoduria matinal no fue diferente a la vespertina (matutina: 305.2± 7.0 vs vespertina: 319.2± 8.8; NS). No hubo diferencia entre las yodurias de los diversos trimestres. En 46 embarazadas (36.9%) la yoduria fue baja sin diferencias entre la matutina y vespertina (matutina: 88.12 ± 5.07 μg/l vs 88.7± 6.2 μg/l; NS), al igual que entre las yodurias matutinas y vespertinas en los tres trimestres de embarazo. De las embarazadas con yodurias <100ug/l, el 45% presentó alteraciones de la función tiroidea. No hubo diferencias significativas respecto a la edad entre las embarazadas con baja y normal EUI. La determinación de yoduria matutina y vespertina permitió detectar un mayor número de embarazadas con baja ingesta de yodo y orientó para la búsqueda de disfunción tiroidea que no se hubiera detectado por no contar nuestra Provincia con un Programa de screening para hipotiroidismo gestacional.<hr/>The urinary iodine excretion (UIE) assay is an effective method to detect reduced iodine intake. UIE was measured in two different samples (morning and evening) from 121 pregnant women, with a turbid-metric method modified by Pino (normal value =150 ug/l). Furthermore, thyroid function was evaluated in pregnant women with UIE &lt;100 ug/l. From 121 pregnant women, the UIE was normal in 75 with similar morning and evening samples (morning: 305.2± 7.0; evening: 319.2± 8.8; p: NS). The UIE did no showed differences in different trimesters and in morning and evening samples. The UIE was low in 46 women (36.9%), without significant differences between morning and evening (morning: 88.12 ± 5.07 μg/l; evening: 88.7± 6.2 μg/l; p: NS). Normal or low UIE were not influenced by the age of pregnant women and 45% of pregnant women with UIE <100ug/l showed impaired thyroid function. Morning and evening study of UIE allowed us to detect a higher number of pregnant women with low iodine intake. This study let us to find thyroid function abnormalities likes a screening method, because in our state there is not a public screening program for gestational hypothyroidism. <![CDATA[<b>Indice de sustancia activa (AKS) distribución percentilar en edades pediátricas</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400005&lng=es&nrm=iso&tlng=es Se programó conocer la distribución percentilar del índice de sustancia activa (AKS), en niños y niñas de 4 a 9 años para disponer de valores de referencia de este indicador. Se calculó en 3.634 niños eutróficos, con talla normal, sanos, de una comunidad urbana marginal, atendidos en el Centro de Atención Nutricional Infantil Antímano (CANIA) entre enero 1999 y diciembre 2007. Se excluyeron niños prematuros, con inicio de estirón puberal y patologías crónicas definidas o en estudio. El cálculo del peso graso necesario para calcular el índice AKS, se hizo con la fórmula de 2 pliegues de Dugdale y Griffiths para niños menores de 150 cm y niñas de menores de 140 cm. Las variables antropométricas fueron medidas por antropometristas estandarizadas con control de calidad cuatrimestral, aplicando las normas recomendadas Internacionalmente. Se obtuvieron los estadísticos descriptivos del índice y de las variables utilizadas en su cálculo, así como los percentiles 3, 10, 25, 50, 75, 90 y 97 del índice. Se aplicó el test de Kolmogorov-Smirnoff, Anova de una vía, Chi cuadrado, test de Tukey y correlaciones divariadas (p < 0,05). El comportamiento del índice evidenció valores mayores en el sexo masculino decrecientes con la edad tanto en los varones como en las hembras, variando la mediana de 1,28 a 1,04 en el sexo masculino y de 1,17 a 0,94 en el femenino. Se encontraron diferencias estadísticamente significativas para cada año de edad y sexo. Se dispone de valores de distribución percentilar del índice AKS para la evaluación nutricional en edades pediátricas, debiéndose validar su efectividad.<hr/>The aim of this study was to discern the percentile distribution of the Active Substance Index (AKS) in boys and girls aged 4 to 9 years in order to obtain reference values for this indicator. This index was calculated in 3,634 healthy and well-nourished children with normal stature from a poor urban community at Centro de Atención Nutricional Infantil Antímano (CANIA), within the period between January 1999 and December 2007. Children with prematurity backgrounds, pubertal growth spurts, or with chronic pathologies, whether defined or under study, were excluded. The Dugdale & Griffiths two-skinfold equation for boys and girls shorter than 150 cm and 140 cm, respectively was used to obtain the fat body mass required to estimate the AKS index. The variables were measured by standardized anthropometrics technicians, with quality control every 4 months as recommended by international standards. Descriptive statistics of the AKS index and variables used for their calculation were obtained, as well as index percentiles 3, 10, 25, 50, 75, 90, and 97. Tests applied included Kolmogorov-Smirnoff, Anova one-way, Chi Square, Tukey and bivariated correlations (p < 0.05). The AKS index behavior exhibited higher values in the boys, decreasing with age in both sexes, ranging from 1.28 to 1.04 in the boys and from 1.17 to 0.94 in the girls. Statistically significant differences were found for each age and sex. These results provide the AKS index percentile distribution values needed for nutritional assessments in pediatric ages. These values should be validated and their effectiveness should be studied. <![CDATA[<b>Evaluación del riesgo nutricional mediante el MNA en una población anciana no institucionalizada</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400006&lng=es&nrm=iso&tlng=es En este trabajo se evaluó el estado nutricional de las personas mayores de 65 años de la provincia de Ourense con el fin de detectar posibles riesgos de desnutrición. Participaron 728 ancianos (63,6% mujeres y 36,4% hombres) de edad media 80,7±7,4 años. Se midieron parámetros antropométricos (peso, distancia talón-rodilla y circunferencia del antebrazo y de la pantorrilla) y se utilizó el cuestionario Mini Nutritional Assessment (MNA). Se observó que el 70% de la población no presentaba un estado nutricional adecuado (el 57,5% está en situación de riesgo de desnutrición y el 12,5% desnutridos); esta situación empeora entre las personas de 65 a 70 años y los mayores de 81 años y entre la población femenina. Los ítems que se observan con mayor frecuencia en la población estudiada son la pérdida involuntaria de peso, ingerir proteínas sólo en una de las comidas del día, consumir poco líquido, pérdida de apetito, tomar más de tres medicamentos al día y tener una movilidad limitada que no le permite salir de casa.<hr/>The objective of this study was to determine the prevalence of the risk of undernutrition by evaluating the nutritional status in a representative sample of older people in Ourense. The total sample was 728 subjects (63,6% woman and 36,4% men) with a mean age of 80,7±7,4 years old. Anthropometric parameters (weight, distance heel-knee, calf circumference and mid-arm circumference) were determined and the MNA (Mini Nutritional Assessment) was applied and 70% of individuals with nutritional problems were identified (57.5% with nutritional risk and 12.5% malnourished). The subjects aged between 65 and 70 years old, 81 and over, and females presented higher nutritional problems. The items that were observed most frequently in the studied population and therefore responsible for this nutritional situation were the involuntary loss of weight, consumption of at least one serving of protein per day, low daily liquid intakes, loss of appetite, taking more than 3 prescription drugs per day and to have a limited mobility. <![CDATA[<b>Retinolemia, vitamin A intake, and blood pressure in the elderly</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400007&lng=es&nrm=iso&tlng=es O objetivo deste estudo foi avaliar a retinolemia e o consumo de alimentos-fonte de vitamina A e a sua associação com os níveis pressóricos arteriais em idosos. Consiste em estudo transversal, com amostra sistemática de 297 idosos inscritos no Programa de Saúde da Família de Camaragibe, Pernambuco, no período de novembro/dezembro de 2003. O status de vitamina A foi avaliado pela retinolemia (HPLC) e pelo consumo de alimentos-fonte de vitamina A (questionário de freqüência alimentar). Os níveis pressóricos arteriais foram classificados segundo a V Diretriz Brasileira de Hipertensão Arterial. Encontrou-se prevalência de retinolemia inadequada (μmol/L) de 26,3% (IC95% 21,4-31,9). A freqüência de consumo alimentar de vitamina A pré-formada (>3x/semana) foi menor (p=0,000) do que dos alimentos pro-vitamina A. A prevalência de hipertensão arterial sistêmica (HAS) foi de 58,6% (IC95% 52,7-64,3), com destaque para a hipertensão sistólica isolada. A retinolemia não mostrou correlação (p> 0,05) com o consumo dietético de vitamina A. Por sua vez, os níveis pressóricos também não apresentaram associação (p> 0,05) com o consumo de vitamina A. No entanto, a média da retinolemia foi maior (p= 0,02) no grupo de idosos classificados com HAS Estágio I, comparada àquela observada para o grupo de idosos com pressão arterial classificada como ótima/normal. Os achados evidenciam a vulnerabilidade dessa população à hipovitaminose A e à HAS. No entanto, o papel da vitamina A na modulação da função endotelial e na resposta inflamatória associada a HAS precisa ser mais bem investigado.<hr/>The objective of this study was to evaluate the retinolemia and consumption of vitamin A rich foods and their association with blood pressure levels in the elderly. This is a cross-sectional study, with a systematic sample of 297 elderly subjects enrolled at the Family Health Program of Camaragibe, Pernambuco, between November/December of 2003. Vitamin A status was assessed by retinolemia (HPLC) and by the consumption of vitamin A rich foods (food frequency questionnaire). Blood pressure levels were classified according to the V Brazilian Guidelines on Hypertension. A prevalence of inadequate retinolemia (μmol/L) of 26.3% (CI95% 21.4-31.9) was found. The frequency of preformed vitamin A intake (>3x/week) was lower (p=0.000) than the provitamin A intake. The prevalence of systemic arterial hypertension (SAH) was 58.6% (CI95% 52.7-64.3). Isolated systolic hypertension was more prevalent among subjects. There was no correlation between retinolemia and vitamin A rich-food intake (p>0.05). In addition, there was no association between blood pressure levels and vitamin A rich-food intake (p>0.05). However, retinolemia in the elderly classified in stage 1 of SAH was higher (p=0.02) than in the elderly with great/normal blood pressure. The findings suggest a vulnerability of these subjects to hypovitaminosis A and SAH. Nevertheless, the role of vitamin A in the endothelial function modulation and inflammatory responses associated to SAH should be addressed in future studies. <![CDATA[<b>Detección de <i>Bacillus cereus</i> toxigénicos en productos lácteos con especias y leches deshidratadas colectadas en Costa Rica</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400008&lng=es&nrm=iso&tlng=es Bacillus cereus es un bacilo Gram-positivo de amplia distribución en la naturaleza y asociado a diversos tipos de alimentos que, bajo ciertas circunstancias causa patologías de diversa índole. Se han descrito cepas diarrogénicas y eméticas basándose en el tipo de toxinas producidas. Con el fin de determinar el riesgo de salud que representa en esta bacteria, se determinó el potencial toxigénico de cepas aisladas a partir de quesos maduros con especias, quesos crema con especias y leches deshidratadas expendidas en San José, Costa Rica, mediante un PCR múltiple con oligonucleótidos específicos para los genes codificantes de las toxinas HBL y Nhe. A partir de 45 muestras recolectadas, se obtuvieron 15 aislamientos de B. cereus, (60% provenientes de queso crema con especias, 7% de leche deshidratada y 13% de queso maduro con especias). Todas las cepas estudiadas presentaron al menos uno de los genes analizados, seis de ellas provenientes de leches deshidratadas y quesos crema, exhibieron evidencia molecular de los genes nheB, nheA, nheC, hblD, hblA y hblC lo cual permite confirmar la correlación descrita para la presencia de los operones codificantes para la HBL y la Nhe. No obstante, la no detección de un gen no puede considerarse como prueba definitiva de su ausencia dado que existen polimorfismos en las secuencias de los genes aquí analizados. Los resultados demuestran que múltiples cepas de B. cereus encontradas en lácteos comprados en Costa Rica contienen los genes necesarios para sintetizar toxinas, por lo tanto es importante el manejo adecuado de estos productos ya que eventualmente pueden representar un riesgo para la salud pública.<hr/>Bacillus cereus is a Gram positive rod widely distributed in nature and associated to different types of food that, under some circumstances, may cause pathology to human beings. Diarrheic and emetic strains have been described based on the type of toxins produced. In order to determine the risk to health represented by this bacteria, the toxigenic potential of strains isolated from cheese with spices, spread cheese with spices and dehydrated milk, all sold in San José, Costa Rica, were determined using a multiplex PCR technique with oligonucleotides specific for the genes coding toxins HBL and Nhe. From 45 samples collected, 15 isolates of B cereus were obtained (60% coming from spread cheese with spices 7% from dehydrated milk and 13% from cheese with spices). All the strains analyzed presented at least one of the genes analyzed; six of them, coming from dehydrated milk and spread cheese, showed molecular evidence of the genes nheB, nheA, nheC, hblD, hblA y hblC, confirming the correlation described for the presence of operons codifying for HBL and Nhe. Nevertheless, the no detection of a gene cannot be considered as a definitive proof of its absence, given the existence of polymorphism in the sequences of the genes analyzed. The results obtained show that multiple of the B cereus strains found in lactic products from Costa Rica have the necessary genes for synthesizing toxins, so the correct handling of these products is very important since they can represent a risk for public health. <![CDATA[<b>Diferencias étnicas y de aculturación en el consumo de alimentos en la Región Metropolitana de Santiago, Chile</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400009&lng=es&nrm=iso&tlng=es Con el objetivo de detectar diferencias en los hábitos de consumo y gasto en alimentos según la etnia del consumidor y grado de aculturación en personas mapuche, se aplicó una encuesta personal a una muestra de 400 personas, estratificada por etnia con afijación simple, en cuatro comunas de la Región Metropolitana de Santiago, Chile. En los resultados empíricos fue posible evidenciar que los hábitos de consumo de los grupos de alimentos que contemplan las Encuestas de Presupuestos Familiares no presentan marcadas diferencias según la etnia del consumidor, aunque el gasto mensual en alimentos es menor en los hogares mapuche. El origen étnico y el grado de aculturación en las personas mapuche están asociados significativamente sólo al consumo de hierba mate y comidas en restaurantes. Los mapuche mantienen prácticas de alimentación propias de su cultura ancestral y de alimentos incorporados más recientemente, como la hierba mate. El grado de aculturación está significativamente asociado al consumo de estos alimentos, los mapuche biculturales tienen mayor probabilidad de consumir una mayor gama de alimentos tradicionales que los mapuche aculturados.<hr/>In order to identify differences in the food consumption and expenditure habits of Mapuches according to their ethnic group as consumers as well as their degree of acculturation, a personal survey was conducted on 400 people stratified by ethnic group in four districts of the Metropolitan Region of Santiago, Chile. The empirical results showed that habits regarding the consumption of food groups included in the Family Budget Survey did not present any significant differences depending on the consumer’s ethnic group, although the monthly expenditure on food is lower in Mapuche households. The ethnic origin and degree of acculturation in Mapuches are only significantly associated with the consumption of mate (herbal infusion) and food in restaurants. Mapuches maintain both food practices belonging to their traditional culture as well as foods incorporated more recently, such as mate. The degree of acculturation is significantly associated with the consumption of these foods; bi-cultural Mapuches present a higher probability of consuming a greater range of traditional foods than accultured Mapuches. <![CDATA[<b>Effect of processing on the antioxidant activity of amaranth grain</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400010&lng=es&nrm=iso&tlng=es As características nutricionais, funcionais e agrícolas do amaranto são responsáveis pelo aumento do interesse por este alimento nas últimas décadas. O grão pode ser cozido, estourado, torrado, extrusado ou moído para ser consumido. Foi avaliado o efeito destes processamentos na atividade antioxidante do grão de amaranto, através das determinações do teor de fenólicos totais e da atividade antioxidante in vitro por dois métodos: inibição da oxidação lipídica pelo sistema β-caroteno/ácido linoléico e índice de atividade antioxidante pelo aparelho Rancimat®. Os processamentos reduziram em média o teor de fenólicos totais do grão de amaranto de 31,7 para 22,0 mg de equivalentes de ácido gálico/g de resíduo seco. Observou-se que o extrato obtido por etanol do grão torrado foi o único a apresentar menor índice de atividade antioxidante (IAA) em relação ao grão cru (1,3 v 1,7). Os processos de extrusão, torração e explosão não alteraram a capacidade de inibição da oxidação lipídica (IOL) do amaranto (55%). Já o cozimento aumentou o IOL (79%), o que pode ter ocorrido devido ao maior tempo de processamento sob alta temperatura (100ºC/10min). Os métodos mais comuns de processamento do grão de amaranto ocasionaram redução do teor de fenólicos totais, no entanto a atividade antioxidante do estourado e do extrusado, avaliada pelos dois métodos, foi semelhante ao do grão cru. O grão de amaranto tanto cru como processado apresenta potencial antioxidante. Polifenóis, antocianinas, flavonóides, tocoferóis, vitamina C e compostos gerados na reação de Maillard podem estar relacionados à atividade antioxidante deste grão.<hr/>Amaranth has attracted increasing interest over recent decades because of its nutritional, functional and agricultural characteristics. Amaranth grain can be cooked, popped, toasted, extruded or milled for consumption. This study investigated the effect of these processes on the antioxidant activity of amaranth grain. Total phenolic content and in vitro antioxidant activity were determined according to two methods: inhibition of lipid oxidation using the β-carotene/linoleic acid system and the antioxidant activity index using the Rancimat® apparatus. The processing reduced the mean total phenolics content in amaranth grain from 31.7 to 22.0 mg of gallic acid equivalent/g of dry residue. It was observed that the ethanol extract from toasted grain was the only one that presented a lower antioxidant activity index compared with the raw grain (1.3 versus 1.7). The extrusion, toasting and popping processes did not change the capacity to inhibit amaranth lipid oxidation (55%). However, cooking increased the inhibition of lipid oxidation (79%), perhaps because of the longer time at high temperatures in this process (100°C/10 min). The most common methods for processing amaranth grain caused reductions in the total phenolics content, although the antioxidant activity of popped and extruded grain, evaluated by the two methods, was similar to that of the raw grain. Both raw and processed amaranth grain presents antioxidant potential. Polyphenols, anthocyanins, flavonoids, tocopherols, vitamin C levels and Maillard reaction products may be related to the antioxidant activity of this grain. <![CDATA[<b>Efecto de la concentración de hidróxido de calcio y tiempo de cocción del grano de maíz (<i>Zea mays</i> L.) nixtamalizado, sobre las características fisicoquímicas y reológicas del nixtamal</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400011&lng=es&nrm=iso&tlng=es Se evaluó el efecto de la concentración de hidróxido de calcio (Ca(OH)2) y tiempo de cocción del grano de maíz sobre las propiedades fisicoquímicas y reológicas durante la nixtamalización tradicional. Se observó que a mayor concentración de Ca(OH)2 y mayor tiempo de cocción del grano, la temperatura de gelatinización aumentó significativamente. El maíz nixtamalizado con 2 g/100g de Ca(OH)2 y 60 min de tiempo de cocción, presentó mayor absorción de calcio, 0.152 g/100g, mostrando un aumento significativo respecto a la concentración inicial (≈500 g/100g). Todas las muestras presentaron un patrón de difracción de rayos X de almidón tipo A, con diferencias en la intensidad de la difracción. La viscosidad aparente del nixtamal disminuyó considerablemente al utilizar condiciones de procesamiento más altas. Se encontró que la capacidad de retención de agua aumentó con la temperatura.<hr/>The effect of calcium hydroxide (Ca(OH)2) concentration and cooking time on physicochemical and pasting properties of maize, during traditional nixtamalization was evaluated. It was observed that the higher the Ca(OH)2 concentration and cooking time the higher the gelatinization temperature. Grain samples treated with 2 g/100g of Ca(OH)2 and 60 min of cooking time presented higher calcium absorption (0.152 g/100g) showing a significant increment (≈500 g/100g). Results of X-ray diffraction showed that all the samples had X-ray diffraction pattern of starch type A, showing differences in the intensity of the diffraction as indicated by the percentage of cristallinity. The apparent viscosity of the nixtamal considerably decreased when the processes conditions were higher. Water retention capacity increased with temperature. <![CDATA[<b>Gluten free cookies prepared with sorghum flour</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400012&lng=es&nrm=iso&tlng=es O sorgo, por ser desprovido de glúten, pode ser utilizado na fabricação de produtos de panificação para indivíduos com Doença Celíaca, que dispõem de poucas alternativas culinárias disponíveis no mercado. Em razão disso, o presente trabalho teve como objetivo desenvolver cookies de chocolate utilizando farinha de sorgo (Sorghum vulgare). Foi aplicado o delineamento experimental fator simplex-lattice com farinhas isentas de glúten: farinha de sorgo (50-100%), farinha de arroz (0-50%) e amido de milho (0-50%); totalizando dez experimentos. As formulações IX e X foram selecionadas por apresentarem melhores características sensoriais. Foram realizadas análises físicas e químicas da farinha de sorgo, dos cookies comerciais com glúten e dos isentos de glúten elaborados neste trabalho. Nas amostras comerciais foram também realizadas análises físicas e sensoriais pela Análise descritiva quantitativa e Escala hedônica. Os resultados das análises físicas e químicas da farinha de sorgo mostraram-se próximos aos preconizados pela legislação. As formulações que apresentaram características sensoriais satisfatórias foram as que continham 58 e 67% de farinha de sorgo, 8 e 17% de farinha de arroz, 33 e 17% de amido de milho, respectivamente. O rendimento das formulações IX e X foi de 0,92 e o volume específico de 1,54 e 1,46cm³/g, respectivamente. A maioria dos atributos sensoriais avaliados dos cookies com farinha de sorgo em relação ao comercial não apresentou diferença estatística significativa em nível de 5%, com exceção da cor e odor. Cem por cento dos provadores com Doença Celíaca atribuíram valores iguais ou superiores a 7 para ambas as amostras, sendo que a maioria atribuiu valor 8. Os resultados demonstraram a viabilidade do uso da farinha mista com sorgo na elaboração de cookies sem glúten.<hr/>Considering that sorghum is a gluten free flour, it could be proposed as an ingredient to produce alternative bakery products for the subjects with Celiac Disease, since they do not have many food options available in the market. For this reason, the main goal of this study is to develop chocolate cookies with sorghum flour (Sorghum vulgare). The experimental design used was the simplex-lattice factor to compare the following variables: sorghum flour (50-100%), rice flour (0-50%) and corn starch (0-50%), totaling up to ten experiments. The formulations IX and X were selected as the ones with the highest sensorial scores The sorghum flour, regular chocolate cookies and gluten free cookies were submitted to physicochemical analysis. Physical and sensorial analysis using Quantitative Descriptive Analysis (QDA) and hedonic analysis were performed for the two cookies preparation. Sorghum flour presented characteristics compared with the described by the food regulation laws. The preparations that presented satisfactory sensorial characteristics were the ones that had 58 and 67% of sorghum flour, 8 and 17% of rice flour, 33 and 17% of corn starch, respectively. The performance for both IX and X formulations was 0,92 and the specific volume was 1,54 and 1,46cm³/g, respectively. When compared with regular cookies, the differences on most of the sensorial attributes evaluated on sorghum cookies were not statistically significant (P < 0.05), except for the color and the odour. All the sensorial scores reached values equal or higher than 7 for both samples and most of them scored 8. The results showed the feasibility of including sorghum flour on the manufacture of gluten free cookies. <![CDATA[<b>Development of mixed drink of coconut water, pineapple and acerola pulp</b>]]> http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400013&lng=es&nrm=iso&tlng=es O objetivo deste trabalho foi desenvolver uma bebida mista a base de água de coco (Cocos nucifera L.) e polpas de abacaxi (Ananas comosus) e acerola (Malpighia emarginata D. C.) na forma de “pronto para beber”, combinando a aceitação sensorial e os componentes nutricionais e funcionais dos frutos. Foram avaliadas 10 formulações de bebidas mistas quanto às determinações físico-químicas, componentes funcionais e atributos sensoriais. Como não houve diferença significativa na aceitação entre as formulações, o produto composto de 65% de água de coco, 15% de polpa de abacaxi e 20% de polpa de acerola foi selecionado baseado na melhor combinação de componentes nutricionais e funcionais. Esta formulação apresentou características requeridas para um novo produto comercial.<hr/>The purpose of the present work was to develop a blended beverage based on green coconut (Cocos nucifera L.) water, pineapple (Ananas comosus) and acerola (Malpighia emarginata D. C.) pulps as a ready to drink product, combining the sensory acceptance, nutritional and functional compounds of these fruits. Ten formulations of mixed beverages were evaluated with regard physicochemical determinations, functional compounds and sensorial attributes. Since here was no significative change in the acceptance of here formulations, the product composed of 65% green coconut water, 15% of pineapple and 20% acerola pulp was selected based on the best combination of nutritional components. This formulation presented the required characteristics for a new commercial product. <link>http://ve.scielo.org/scielo.php?script=sci_arttext&pid=S0004-06222009000400014&lng=es&nrm=iso&tlng=es</link> <description/> </item> </channel> </rss> <!--transformed by PHP 12:08:21 12-08-2026-->