Hydrothermal treatment of maize: Changes in physical, chemical, and functional properties.

The objective of this work was to assess the effects of a traditional parboiling treatment on physical, chemical and functional properties of yellow maize kernels. For this, maize kernels were subjected to the three main stages of a traditional parboiling process (soaking, steaming, and drying) at different moisture contents (15%, 25%, or 35%), and different pressure steaming times (0, 15, or 30 min). Kernels were evaluated for physical and chemical changes, while manually generated endosperm fractions were further evaluated for nutritional and functional changes. The parboiling process negatively altered the maize kernels properties by increasing the number of kernels with burst pericarp and decreasing the total carotenoid content in the endosperm by 42%. However, the most intense conditions (35% moisture and 30 min steam) lowered the number of broken kernels by 41%, and the number of stress cracks by 36%. Results also demonstrated that soaking enhanced the nutritional value of soaked yellow maize by increasing the thiamine content and the bound phenolic content in the endosperm fraction up to 102%. The proper implementation of this hydrothermal treatment could lead to significant enhancements in nutritional and functionality of maize products.

Effect of cooking methods on the stability of thiamin and folic acid in fortified rice.

Rice fortification offers great potential to deliver essential micronutrients to a large part of the world population. However, high temperatures required for cooking rice are deleterious to thermally labile micronutrients. This study evaluated the content and stability of thiamin and folic acid in fortified rice after different cooking methods (stir-frying, boiling, cooking in a microwave oven and boiling in a Food Service). The analyses were performed by High Performance Liquid Chromatography (HPLC). The fortified rice showed the highest thiamin content (0.97 mg/kg) and retention (65.4%) when cooked in microwave oven, and for folic acid the lowest content (0.17 mg/kg) and the highest retention (96.11%) when cooked in a Food Service and stir-fried, respectively. In conclusion, the stability of thiamin and folic acid varied according to the cooking method and the stability of folic acid presented higher percentages in relation to thiamin in the different methods. [Formula: see text].

Compositional studies and biological activities of some mash bean (Vigna mungo (L.) Hepper) cultivars commonly consumed in Pakistan.

BACKGROUND: In recent years, the desire to adopt a healthy diet has drawn attention to legume seeds and food products derived from them. Mash bean is an important legume crop used in Pakistan however a systematic mapping of the chemical composition of mash bean seeds is lacking. Therefore seeds of four mash bean (Vigna mungo (L.) Hepper, family Leguminoseae) cultivars (NARC-Mash-1, NARC-Mash-2, NARC-Mash-3, NARC-Mash-97) commonly consumed in Pakistan have been analyzed for their chemical composition, antioxidant potential and biological activities like inhibition of formation of advanced glycation end products (AGE) activity and tyrosinase inhibition activity. RESULTS: The investigated cultivars varied in terms of biochemical composition to various extents. Mineral composition indicated potassium and zinc in highest and lowest amounts respectively, in all cultivars. The amino acid profile in protein of these cultivars suggested cysteine is present in lowest quantity in all cultivars while fatty acid distribution pattern indicated unsaturated fatty acids as major fatty acids in all cultivars. All cultivars were found to be rich source of tocopherols and sterols. Fourier transform infrared spectroscopy (FTIR) fingerprints of seed flour and extracts indicated major functional groups such as polysaccharides, lipids, amides, amines and amino acids. Results indicated that all investigated cultivars possessed appreciable antioxidant potential. CONCLUSIONS: All cultivars are rich source of protein and possess sufficient content of dietary fiber, a balanced amino acid profile, low saturated fatty acids and antioxidant capacity that rationalizes many traditional uses of seeds of this crop besides its nutritional importance. The collected data will be useful for academic and corporate researchers, nutritionists and clinical dieticians as well as consumers. If proper attention is paid, it may become an important export commodity and may fetch considerable foreign exchange for Pakistan.

Compositional studies and biological activities of some mash bean (Vigna mungo (L) Hepper) cultivars commonly consumed in Pakistan

BACKGROUND: In recent years, the desire to adopt a healthy diet has drawn attention to legume seeds and food products derived from them. Mash bean is an important legume crop used in Pakistan however a systematic mapping of the chemical composition of mash bean seeds is lacking. Therefore seeds of four mash bean (Vigna mungo (L.) Hepper, family Leguminoseae) cultivars (NARC-Mash-1, NARC-Mash-2, NARC-Mash-3, NARC-Mash-97) commonly consumed in Pakistan have been analyzed for their chemical composition, antioxidant potential and biological activities like inhibition of formation of advanced glycation end products (AGE) activity and tyrosinase inhibition activity. RESULTS: The investigated cultivars varied in terms of biochemical composition to various extents. Mineral composition indicated potassium and zinc in highest and lowest amounts respectively, in all cultivars. The amino acid profile in protein of these cultivars suggested cysteine is present in lowest quantity in all cultivars while fatty acid distribution pattern indicated unsaturated fatty acids as major fatty acids in all cultivars. All cultivars were found to be rich source of tocopherols and sterols. Fourier transform infrared spectroscopy (FTIR) fingerprints of seed flour and extracts indicated major functional groups such as polysaccharides, lipids, amides, amines and amino acids. Results indicated that all investigated cultivars possessed appreciable antioxidant potential. CONCLUSIONS: All cultivars are rich source of protein and possess sufficient content of dietary fiber, a balanced amino acid profile, low saturated fatty acids and antioxidant capacity that rationalizes many traditional uses of seeds of this crop besides its nutritional importance. The collected data will be useful for academic and corporate researchers, nutritionists and clinical dieticians as well as consumers. If proper attention is paid, it may become an important export commodity and may fetch considerable foreign exchange for Pakistan.

Presence and stability of B complex vitamins in bee pollen using different storage conditions.

This study has the objective of evaluating the stability of B complex vitamins and its vitamers, for a period of 1year of storage. The pollen samples were stored under room temperature (with and without light) and frozen. The vitamins were quantified by HPLC with fluorescence detection. All proposed vitamins were found in the samples and the dehydration process did not interfere in vitamin content. The variations were (dry basis): 0.59-1.09mg/100g (B(1)); 1.73-2.56 (B(2)); 6.43-15.34 (PP) and 0.33-0.68 (B(6)). After 1year of storage, it can be stated that vitamin B(1) concentration remained constant, while for the others, the concentration loss was dependent on time rather than on storage conditions. All samples were considered vitamin B(2) sources. The influence of the storage time in the concentrations of vitamin B(6) and PP was explained mathematically, through linear regression equations of multivariate analysis.

Optimization of thermal processing of canned mussels.

The design and optimization of thermal processing of solid-liquid food mixtures, such as canned mussels, requires the knowledge of the thermal history at the slowest heating point. In general, this point does not coincide with the geometrical center of the can, and the results show that it is located along the axial axis at a height that depends on the brine content. In this study, a mathematical model for the prediction of the temperature at this point was developed using the discrete transfer function approach. Transfer function coefficients were experimentally obtained, and prediction equations fitted to consider other can dimensions and sampling interval. This model was coupled with an optimization routine in order to search for different retort temperature profiles to maximize a quality index. Both constant retort temperature (CRT) and variable retort temperature (VRT; discrete step-wise and exponential) were considered. In the CRT process, the optimal retort temperature was always between 134 °C and 137 °C, and high values of thiamine retention were achieved. A significant improvement in surface quality index was obtained for optimal VRT profiles compared to optimal CRT. The optimization procedure shown in this study produces results that justify its utilization in the industry.

Chemical stability study of vitamins thiamine, riboflavin, pyridoxine and ascorbic acid in parenteral nutrition for neonatal use.

BACKGROUND: The objective of this work was to study the vitamins B1, B2, B6 and C stability in a pediatric formulation containing high amounts of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulfate, pediatric vitamins and trace elements under different conditions using developed and validated analytical methods. METHODS: The study was carried out during 72 h with formulations packaged in recommended storage temperature (4°C) and 25°C, with and without photoprotection. RESULTS: The results showed that the methodologies used for assessing the chemical stability of vitamins B1, B2, B6 and C in the formulation were selective, linear, precise and accurate. The vitamins could be considered stable in the formulation during the three days of study if stored at 4°C. When stored at 25°C vitamin C presented instability after 48 h. CONCLUSION: The pediatric formulation containing high amount of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulphate, pediatric vitamins and trace elements packaged in bag-type trilaminate presented a shelf life of the 72 h, when maintained under refrigeration, between 2°C and 8°C. This shelf life was measured considering the vitamins studied. Further studies are needed including all the vitamins present in this formulation.

Maternal thiamine restriction during lactation induces cognitive impairments and changes in glutamate and GABA concentrations in brain of rat offspring.

Maternal thiamine deficiency causes changes in cellular energy metabolism that can interfere with offspring brain development. The purpose of the present study was to investigate the effects of thiamine restriction, during lactation, on offspring neurochemistry and cognitive parameters. Male young (31 days old) and adult (75 days old) rats, from control and restricted mothers, were submitted to spatial learning and memory assessment. GABAergic and glutamatergic parameters were measured in thalamus, prefrontal cortex and hippocampus by high performance liquid chromatography (HPLC). The young animals were assessed immediately after thiamine restricted period; the adults, however, underwent a recovery period of 45 days. In young rats, thiamine restriction significantly hindered body weight gain and learning speed; however, it did not affect the brain weight, GABA and glutamate parameters in any of the brain assessed areas. In adult rats the body weight gain was significantly hampered by thiamine restriction, while brain weight and spatial task were not affected. Also, in adult offspring, maternal thiamine restriction significantly decreased the glutamate and GABA contents in the three assessed brain areas and thalamus, respectively. One possible explanation for these findings is that an adjustment of the inhibitory (GABAergic) and stimulatory (glutamatergic) neuromodulation systems occurs, in order to reverse the behavioral deficits detected in young rats but not in adult ones. The present data show, for the first time, that maternal thiamine restriction during lactation induces cognitive impairments and neurochemical changes in offspring, corroborating the important role of thiamine in brain development.

Multiobjective optimization approach: thermal food processing.

The objective of this study was to utilize a multiobjective optimization technique for the thermal sterilization of packaged foods. The multiobjective optimization approach used in this study is based on the optimization of well-known aggregating functions by an adaptive random search algorithm. The applicability of the proposed approach was illustrated by solving widely used multiobjective test problems taken from the literature. The numerical results obtained for the multiobjective test problems and for the thermal processing problem show that the proposed approach can be effectively used for solving multiobjective optimization problems arising in the food engineering field.

Desenvolvimento e validação de métodos cromatográficos e avaliação da estabilidade de vitaminas hidrossolúveis em alimentos / Development and validation of chromatographic methods and stability study of hidrossoluble vitamins in food

A adição de vitaminas aos produtos industrializados tornou-se prática comum para as indústrias de alimentos e os teores adicionados devem obedecer à legislação brasileira durante toda a vida de prateleira dos produtos. Sabendo da sensibilidade das vitaminas a fatores como oxigênio, luz e calor, é essencial conhecer o comportamento destes compostos no alimento frente aos fatores críticos. Informações confiáveis sobre teores de vitaminas somente podem ser obtidas com métodos analíticos validados. A perspectiva deste trabalho é desenvolver metodologias analíticas por cromatografia líquida de alta eficiência para determinação de vitaminas B1, B2, B6 e PP, validá-las e então analisar amostras submetidas a diferentes condições de estocagem durante 10 meses para verificação do comportamento destas vitaminas

[Thiamine retention as a function of thermal processing conditions: canned salmon]. / Retención de tiamina como función de las condiciones de proceso térmico en salmón en conserva.

The present work studied the effect of different treatments at high temperatures on the nutritional properties of thiamine retention and color measurement experimentally. Canned salmon (Salmo salar) was processed under different temperatures and time conditions (110 degrees C for 135 minutes; 114 degrees C for 89 minutes; 118 degrees C for 69 minutes and 121 degrees C for 62 minutes). Thiamine was determined by HPLC before and after the process. Color changes, due to processing conditions, were also measured utilizing a Hunter colorimeter. The canning was prepared in 300 x 407 cans and sterilized until Fo value reached 6 min. The nutritional value or index represented by the B1 vitamin or thiamine was affected by high temperature and time exposition. The lowest loss of thiamine of 19.2% was obtained in the canned salmon sterilized at 114 degrees C for 89 minutes. The color in canned salmon was different from the raw material, with a severe loss of red color and a greater clarity of the meat.

Nível de tiamina no miocárdio, área transversa e número de núcleos de cardiomiócitos de ratos em uso de furosemida / Myocardial thiamine level, cardiomyocyte cross-sectional area and nuclei number in furosemide-treated rats

Objetivo: Avaliar os níveis miocárdicos de tiamina e área transversa e número de núcleos de cardiomiócitos de ratos em uso de furosemida. Métodos: 24 ratos foram estratificados em 4 grupos: 2 grupos receberam furosemida por via intraperitoneal e 2 receberam solução salina, por 21 dias. Dois destes grupos receberam ração-padrão, e 2 ração pobre em tiamina. Os níveis miocárdicos de tiamina foram avaliados por: dosagem de tiamina pirofosfato (TPP) por HPLC, e medidas de atividade da transcetolase miocárdica(ATm) e do efeito da tiamina pirofosfato (ETPP). Métodos estereológicos foram utilizados para a obtenção da área transversa (Acmy) e número de núcleos (Ncmy) dos cardiomiócitos. Resultados: as médias e desvios-padrão de TPP, ATm, ETPP, Acmy e Ncmy foram, respectivamente: Grupo 1 - 133,7 maior ou menor que 17,9ng/100 microlitro de tecido homogeneizado; 173 maior ou menor que 20 micrograma.hexose/ml/h; 3,6 maior ou menor que 1,9 por cento; 808 maior ou menor que 8 milhões; Grupo 2 - 160,2 maior ou menor que 23,2ng/100 microlitro de tecido homogeneizado; 1634 maior ou menor que 137 micrograma.hexose/ml/h; 2,2 maior ou menor que 1,4 por cento; 961 maior ou menor que 59 micrometro2; 63 maior ou menor que 2 milhões; Grupo 3 - 73,5 maior ou menor que 8,6ng/100 microlitro de tecido homogeneizado; 715 maior ou menor que 123 micrograma.hexose/ml/h; 39,8 maior ou menor que 9,8 milhões por cento; 963 maior ou menor que 2 micrometro2; 59 maior ou menor que 4 milhões Grupo 4 - 82,1 maior ou menor que 9ng/100 microlitro de tecido homogeneizado; 863 maior ou menor que 75 micrograma.hexose/ml/h; 26,2 maior ou menor que 11,9 por cento; 1061 maior ou menor que 33 micrometro2; 63 maior ou menor que 5 milhões. Conclusão: A furosemida não reduziu o nível de tiamina no miocárdio, nem alterou a área transversa e o número de núcleos de cardiomiócitos nos animais estudados.

Direct determination of diclofenac in pharmaceutical formulations containing B vitamins by using UV spectrophotometry and partial least squares regression.

This work proposes a simple and rapid analytical procedure for determination of diclofenac (DCF) in the presence of B vitamins, based on UV measurements and partial least squares (PLS). The interference of thiamine (THI) and pyridoxine (PYR) were modelled using an experimental design constructed in the ranges of 10-50 micromoll(-1) for DCF and THI and 15-75 micromoll(-1) for PYR. The procedure was repeated at five different pH values (between 3 and 6) and the best results were observed at pH 5, presenting a root mean square error of prediction (RMSEP) of 0.80 micromoll(-1) for DCF. The procedure was successfully applied to simultaneous determination of DCF, THI and PYR in synthetic mixtures and in a pharmaceutical formulation that contains a simple excipient (lactose). For determination of a more complex formulation that contains 15 different substances in the excipient, including some UV absorbing ones, the procedure was only able to determine DCF, since the excipient interferences disturbed THI and PYR predictions. Figures of merit, such as selectivity, analytical sensitivity, limit of detection and precision were determined for the DCF prediction model and the determinations were verified by an independent method, HPLC.

Simultaneous detection of thiamine and its phosphate esters from microalgae by HPLC.

We present an easy and sensitive method for measuring thiamine and its phosphate esters in small biological samples of microalgae (Amphidinium carterae Hulburt and Nitzschia microcephala Grun). The method consists of extraction of thiamine and its derivatives in acid solution, followed by liquid chromatography with fluorescence detection. The detection limit is as low as 15 fmol of thiamine. For comparison to microalgae, the method has been applied to evaluate thiamine levels in the crustacean Artemia salina Leach and is suitable for nutritional studies of the food web of the Baltic salmon, which suffers from thiamine deficiency. This method of HPLC analysis can be readily utilized to follow uptake and interconversion of thiamine and its phosphate esters in many micro- and macroalgae.

Validación del método analítico para la determinación de 3 vitaminas hidrosolubles en un suplemento vitamínico / Validation of the analytical method for the determination of 3 vitamins hydrosoluble in a vitamin supplement

Se presentan los resultados obtenidos en la validación de un método analítico por cromatografía líquida de alta resolución, para la determinación de tiamina mononitrato, piridoxina clorhidrato y nicotinamida en el suplemento nutricional neovitamin II, el cual se diseñó para separar las vitaminas entre sí, con la utilización de una columna RP-18 de 25 cm y un detector UV-Visible. Dicho método se empleó para el control de la calidad y la estabilidad de este producto. El método fue validado siguiendo una metodología de trabajo elaborada previamente en un Protocolo de Validación, donde se analizaron diferentes parámetros como son: linealidad, exactitud, precisión, selectividad, límites de detección y cuantificación, adecuación del sistema y estabilidad de las soluciones. Se obtuvieron resultados satisfactorios y se comprobó de esta forma la validez del método analítico (AU)

Validación del método analítico para la determinación de 3 vitaminas hidrosolubles en un suplemento vitamínico / Validation of the analytical method for the determination of 3 vitamins hydrosoluble in a vitamin supplement

Se presentan los resultados obtenidos en la validación de un método analítico por cromatografía líquida de alta resolución, para la determinación de tiamina mononitrato, piridoxina clorhidrato y nicotinamida en el suplemento nutricional neovitamin II, el cual se diseñó para separar las vitaminas entre sí, con la utilización de una columna RP-18 de 25 cm y un detector UV-Visible. Dicho método se empleó para el control de la calidad y la estabilidad de este producto. El método fue validado siguiendo una metodología de trabajo elaborada previamente en un Protocolo de Validación, donde se analizaron diferentes parámetros como son: linealidad, exactitud, precisión, selectividad, límites de detección y cuantificación, adecuación del sistema y estabilidad de las soluciones. Se obtuvieron resultados satisfactorios y se comprobó de esta forma la validez del método analítico

Early response to the effect of iron fortification in the Venezuelan population.

In Venezuela a severe economic crisis beginning in 1983 provoked a progressive reduction of the quality and quantity of food consumed by the low socioeconomic strata of the population. In these strata, which represent > or = 80% of the Venezuelan population, we had seen a continuous increase in the prevalence of iron deficiency during that recent decade. As a result, in 1993 the Venezuela Government created the Special Commission for Enrichment of Foods. That same year a fortification program began in which precooked yellow and white maize and wheat flours were enriched with 20 and 50 mg Fe (as ferrous fumarate)/kg flour, respectively. The corn flour was also enriched with vitamin A, thiamine, riboflavin, and niacin, whereas the wheat flour was enriched with these same vitamins, except vitamin A. These two cereals represent 45% of the total energy consumed daily by the low socioeconomic strata of the population. A preliminary survey carried out in Caracas in 1994 in a population of 307 children aged 7, 11, and 15 y showed that the prevalence of iron deficiency determined by measuring the serum ferritin concentration and the prevalence of anemia were reduced from 37% and 19%, respectively, in 1992 to 15% and 10%, respectively in 1994.

Separaçäo de vitaminas pela eletroforese em papel / Separation of vitamins by paper electrophoresis

As vitaminas A (retino), B1 (tiamina), B6 (piridoxina), B12 (cianocobalamina), C (ácidoo ascórbico) e E (alfa-tocoferol), foram analisadas por eletroforese inidimensional em papel (qualitativo Klabin), usando como eletrólito soluçöes aquosas de carbonato de amônio 0,050, 0,075 e 0,100 M, sob um gradiente de potencial de 12,6V/cm. As melhores separaçöes ocorreram com o eletrólito nas concentraçöes 0,050 M (30 e 45 minutos) e 0,100 (45 e 60 minutos), quando 05 (cinco) vitaminas foram perfeitamente separadas: A (ou B6)-B1-B12-C e E