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The effects of the dry heat treatment (DHT) temperature (20, 50, 100, 150, 200 °C) on the structure of wheat flour and on the texture and in vitro starch digestibility of breads were investigated. X-ray diffraction and FTIR showed that increasing temperatures produced reduction of the hydrated starch structures, increased crystallinity and molecular order of starch chains, and had important effects on the gluten secondary structure. High treatment temperatures produced significant reductions in rapidly digestible starch (RDS) (53.21% at 20 °C, 22.24% at 200 °C), and the slowly digestible starch fraction tended to increase (26.12% at 20 °C, 31.48% at 200 °C). On the other hand, bread hardness showed a significant increase from 11.25 N at 20 °C to 49.53 N at 200 °C, the latter value being similar to that reported for bread crusts. Principal component analysis results showed that the flour and bread characteristics were drastically changed by the DHT, with 100 °C representing a critical temperature. Below 100 °C, breads showed textural characteristics close to that of the control bread, with reduced RDS fractions, while at temperatures above 100 °C, hardness was boosted.

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A farinha de trigo é obtida por moagem e suas características são influenciadas por condições a que são submetidas na producão. A contaminação deste produto pode se dar desde a infestação dos grãos de trigo por pragas do campo até o seu ambiente de armazenagem. Com isso torna-se necessário o uso das boas práticas de produção para garantir a qualidade do produto e evitar riscos ao consumidor. Neste sentido, a ANVISA estabelece um limite de tolerância para avaliação de matérias estranhas macroscópicas e microscópicas em alimentos. Este trabalho buscou coletar, analisar e verificar a qualidade de amostras de farinha de trigo tipo 1, afim de verificar sua adequação frente a legislação vigente, tendo como base o método da “Association of Official of Analytical Chemists International” (AOAC). Os resultados mostraram, presença de matérias estranhas, porém dentro dos limites estabelecidos, demonstrando qualidade em relação à presença de sujidades.(AU)

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A farinha de trigo é obtida por moagem e suas características são influenciadas por condições a que são submetidas na producão. A contaminação deste produto pode se dar desde a infestação dos grãos de trigo por pragas do campo até o seu ambiente de armazenagem. Com isso torna-se necessário o uso das boas práticas de produção para garantir a qualidade do produto e evitar riscos ao consumidor. Neste sentido, a ANVISA estabelece um limite de tolerância para avaliação de matérias estranhas macroscópicas e microscópicas em alimentos. Este trabalho buscou coletar, analisar e verificar a qualidade de amostras de farinha de trigo tipo 1, afim de verificar sua adequação frente a legislação vigente, tendo como base o método da “Association of Official of Analytical Chemists International” (AOAC). Os resultados mostraram, presença de matérias estranhas, porém dentro dos limites estabelecidos, demonstrando qualidade em relação à presença de sujidades.

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Industrial wheat quality flour is related to gluten amount in grain. This study aimed to evaluate the relationship between high molecular weight (HMW) glutenins obtained by SDS-PAGE and gluten strength (W) obtained by the alveograph test and cropping environmental effect on wheat flour quality for Brazilian industry. Fifty-one cultivars/breeding lines were evaluated in three environments. The W value and HMW glutenin score were evaluated by SDS-PAGE. The environment effects on wheat flour were also evaluated. There was a relationship between the W value used in wheat flour industrial classification and score 10 of HMW glutenins, but there was no relation with scores 9 or lower. Cultivars/breeding lines with score 10 of HMW glutenin are less susceptible to environmental effects and produce breeding type wheat flour (W value ≥300) of interest for industry. The cultivars/breeding lines with score 10 for HMW glutenins is the main choice for a wheat breeding program.

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The transfer of agronomically useful genes from wild wheat species into cultivated wheat is one of the most effective approaches to improvement of wheat varieties. To evaluate the transfer of genes from Dasypyrum villosum into Triticum aestivum, wheat quality and disease resistance was evaluated in two new translocation lines, T1DL•1V#3S and T1DS•1V#3L. We examined the levels of stripe rust resistance and dough quality in the two lines, and identified and located the stripe rust resistant genes and high molecular weight glutenin subunit (HMW-GS) genes Glu-V1 of D. villosum. Compared to the Chinese Spring (CS) variety, T1DL•1V#3S plants showed moderate resistance to moderate susceptibility to the stripe rust races CYR33 and Su11-4. However, T1DS•1V#3L plants showed high resistance or immunity to these stripe rusts. The genes for resistance to stripe rust were located on 1VL of D. villosum. In comparison to CS, the dough from T1DS•1V#3L had a significantly shorter developing time (1.45 min) and stable time (1.0 min), a higher weakness in gluten strength (208.5 FU), and a lower farinograph quality index (18). T1DL•1V#3S had a significantly longer developing time (4.2 min) and stable time (5.25 min), a lower weakness in gluten strength (53 FU) and a higher farinograph quality index (78.5). We also found that T1DS•1V#3L had reduced gluten strength and dough quality compared to CS, but T1DL•1V#3S had increased gluten strength and dough quality. The results of SDS-PAGE analysis indicated that Glu-V1 of D. villosum was located on short arm 1VS and long arm 1VL. These results prove that the new translocation lines, T1DS•1V#3L and T1DS•1V#3L, have valuable stripe rust resistance and dough quality traits that will be important for improving wheat quality and resistance in future wheat breeding programs.

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Corn flour and maize meal fortification can benefit the consumer when the added nutrient contents are in amounts appropriate to address nutrient gaps. Legislative instruments (standards and regulations) are needed to provide guidance to the producers and food control authorities. We reviewed a number of national standards and regulations of fortified corn flour and maize meal and identified constraints; contrary to current belief, the practice of using minimum contents or ranges of nutrients has caused confusion, misinterpretation, and conflict, and should therefore be abandoned. On the basis of the findings, a model of fortification legislation is proposed, in which the additional content and the expected average nutrient content in a final product are recommended as the main parameters for quality control and enforcement. For labeling, the average content, or one adjusted to the expected content of the product at the market, can be applied. Variation in micronutrient contents should still be checked to ensure homogeneity but with adherence to clear procedures of sampling and testing, which should be part of the standards and regulations.

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BACKGROUND: The first genetically modified (GM) maize lines were approved for trading in Brazil after December 2007 and they were T25, MON810, Bt11, NK603 and GA21. The polymerase chain reaction (PCR) method was employed to monitor the presence of Bt11 and nested PCR was used to detect the presence of Bt176 in 81 maize-derived products (maize flour, corn meal, maize flour flakes and polenta) that were sold in Brazilian market from 2005 to 2007, before the release of GM maize in Brazil. RESULTS: The PCR detection limit for Bt11 was 10 g kg(-1) and for nested PCR of Bt176 it was 1 g kg(-1). All Brazilian samples analyzed showed no positive signal for these GM maize events. CONCLUSION: Bt11 and Bt176 GM maize lines were not detected by specific PCR in 81 maize-derived food samples sold in Brazil from 2005 to 2007, before the commercial release of GM maize in Brazil. These Brazilian food industries were in compliance with the rules stipulated by the current legislation with respect to consumer requirements about GMO labeling.

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BACKGROUND: Amaranth is a little-known culture in Brazilian agriculture. Amaranthus cruentus BRS Alegria was the first cultivar recommended by Embrapa for the soil of the Brazilian scrubland. In order to evaluate the potential of this species in the production of flour, starch and protein concentrates, the latter products were obtained from A. cruentus BRS Alegria seeds, characterized and compared with the products obtained from the A. caudatus species cultivated in its soil of origin. RESULTS: The seeds of A. cruentus BRS Alegria furnished high-purity starch and flour with significant content of starch, proteins, and lipids. The starch and flour of this species presented higher gelatinization temperatures and formed stronger gels upon cooling compared with those obtained from the A. caudatus species. This is due to their greater amylose content and a difference in the composition of the more important fatty acids, such as stearic, oleic and linoleic acids, which indicates that they have greater heat stability. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and differential scanning calorimetry revealed the presence of albumins, globulins, glutelins and prolamins in the protein concentrate, which was obtained as a byproduct of starch production. CONCLUSION: Amaranthus cruentus BRS Alegria has potential application in the production of flour, starch and protein concentrates, with interesting characteristics for use as food ingredients.

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Anemia caused by iron defi ciency is very prevalent in Brazil, and so the government decided that wheat flour should be fortified with iron. This paper presents the perceptions of the wheat milling industry on the Brazilianlaw which determines flour fortification. Professionals responsible for implementing the law, and representing 60% of the Brazilian wheat flourmarket, were interviewed and the answers analyzed using the method of Collective Discourse of the Subjects. This method combines the main ideas of the subjects, using their own verbal expressions, to reveal their perceptions. Interpretation of the results showed that millers agree with the law; how everthey complained about the authoritarian way in which it was introduced. They had previously asked the government for advertising to educate the consumers, but this was not done. The millers do not believe that the population of low socioeconomic status will be benefitted by this law because of the high cost of wheat-derived products. The millers say they are observing the law, in spite of initial technological deficiencies. These have been solvedby using the services of micronutrient suppliers and over-dosing the flour.Wheat flour for domestic use is usually fortified with reduced iron, but other iron compounds are used in the flour supplied to industry. In the perceptionof the millers, the fortification issues are more administrative and politicalthan technical.

Debido a la elevada prevalencia en el paísde anemia por défi cit de hierro, el gobiernobrasileño decidió implantar la fortificaciónde la harina de trigo con este elemento. Estetrabajo expone la opinión de la industriamolinera sobre la resolución que determinala fortificación. Fueron entrevistados los profesionales responsables por la implementación de la medida que su ministran 60% de laharina al mercado brasileño. Las respuestas seanalizaron utilizando el método del Discursodel Sujeto Colectivo. Este método combina las principales ideas de los entrevistados pararevelar sus opiniones sobre el tema. El análisis de los resultados mostró que los molinerosestán de acuerdo con la legislación, pero no concuerdan con la forma autoritaria como fue presentada. Ellos habían solicitado al gobiernola realización de propaganda educativa delos consumidores, que no fue realizada. La industria no cree que la población de bajo poder adquisitivo será beneficiada por la medida, debido al elevado costo de los derivados detrigo. Afirman estar cumpliendo la legislación, a pesar de las dificultades tecnológicas, que hansido resueltas con sobredosis de micronutrientesen las harinas. La harina de trigo para uso doméstico es generalmente fortificada con hierroreducido, pero otros compuestos de hierro son usados para la harina industrial. El juicioque la industria tiene es que los problemas defortificación son más políticos y administrativosque técnicos.

A anemia provocada pela deficiência de ferro tem alta prevalência no Brasil e, assim sendo, o governo decidiu fortificar a farinha de trigo com ferro. Este trabalho apresenta a percepção da indústria moageira do trigo sobre a Resolução brasileira que determina a fortificação.Profissionais responsáveis pela implementação da legislação e que fornecem 60% da farinha do mercado brasileiro foram entrevistados e suas respostas foram analisadas usando o métododo Discurso do Sujeito Coletivo. Este combina as principais idéias dos entrevistados, usando suas expressões verbais para revelar suas percepções sobre o assunto. A interpretação dos resultados mostrou que os moleiros concordam com a legislação, no entanto reclamam sobre a forma autoritária como esta foi apresentada. Eles haviam solicitado ao governo que realizas se propaganda para educar os consumidores, mas isto não foi feito. A indústria não acredita que as populações de baixo poder aquisitivo serão atendidas pela legislação, devido ao alto custo dos produtos derivados do trigo. Eles afirmam estar cumprindo a legislação, apesar das dificuldades tecnológicas, que têm sido resolvidas com a sobre-dosagem na farinha dos micronutrientes, cujos fornecedores incluem serviços laboratoriais. A farinha de trigo para uso doméstico é geralmente fortificada com ferroreduzido, mas outros compostos de ferro são usados para a farinha industrial. Na percepção da indústria, os problemas da fortificação são mais político-administrativos que técnicos.

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Eleven experimental and three commercial white quality protein maize (QPM) hybrids and two regular endosperm controls were planted at Celaya, Guanajuato, Mexico with the aim of comparing grain physical characteristics, protein quality, lime-cooking and tortilla making properties. All genotypes were planted under irrigation using a density of 80,000 plants/ha and fertilized with 250 kg N-60 P-60 K per hectare. When compared with the controls these QPM genotypes had lower test (77.4 vs. 76.5 kg/hL) and 1,000 kernel weights (327 vs. 307 g), softer endosperm texture (2.5 vs. 1.8 where 1 = soft, 2 intermediate and 3 hard endosperm), lower protein (10.0 vs. 8.0%), higher nixtamal water uptake after 30 min lime-cooking (50.0 vs. 53.1% moisture) and lower pericarp removal scores. The lower thousand-kernel weight and softer endosperm texture observed in the QPM genotypes lowered the optimum lime-cooking time as estimated with regression equations. Most QPM genotypes had higher amounts of lysine, tryptophan and albumins/globulins when compared with the controls. QPMs HEC 424973, HEC 774986 and HEC 734286 had the best grain traits for nixtamalization and therefore the best potential for industrial utilization. The commercial use of these QPM hybrids should benefit Mexicans who depend on tortillas as the main staple.

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Mapuey (Dioscorea trifida), is a tropical America tuber, which is appreciated for its taste and fine texture. It has not been fully cultivated in Venezuela, even though products like its flour and starch could replace conventional used products. In this work physical and chemical characteristic of flours from mapuey (varieties white and purple), were assessed, as well as some of their micronutrients. Physical, physicochemical and rheological properties, and chemical composition of isolated starches were also evaluated. Flours were obtained by a drying process and starches by aqueous extraction. Chemical analysis was performed following standard methodologies. The flour yield of purple mapuey was the highest, as was its protein content. The minerals content, showed significant differences between both varieties, presenting purple variety a higher content. Isolated starches showed high purity, this was corroborated by the scanning electron microscopy which showed irregular shaped granules (oval and elongated), with truncated end and smooth surfaces. Purple mapuey granules were smaller. Both varieties exhibited a B type diffraction pattern. The greater swelling power and water absorption capacity was presented by white mapuey, while the highest solubility was shown by the purple one. The white mapuey had maximum viscosity, as well as the highest value of breakdown, suggesting more fragile granules. Setback was lower in the white mapuey, suggesting lower tendency to retrogradation. The purple mapuey although, it showed a higher amylose content, presented lower consistency, even though the difference was not relevant.

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In the present study, 11 maize varieties were analyzed for their nixtamalization cooking quality. The 11 varieties were grown in the same locality and in the same year. The samples were evaluated for their physical characteristics, such as moisture content averaging 13.3%, average 1000 kernel weight (312.5 g), grain hardness through density (1.28 g/ml) and percent floaters (9.5%). These data indicated that all maize varieties had a hard endosperm which is recommended for the nixtamalization cooking process. The 11 varieties were formed on the average by 5.7% seed coat, 11.5% germ and 82.8% endosperm. The low seed coat content suggest a low solids loss during processing. Cooking quality evaluation was done by applying a standard lime cooking procedure to all varieties. An average solid loss of 3.2% was measured, with 0.8% of seed coat still attached to the endosperm. Water absorption at the end of cooking was 40.8% without soaking and 46.9% at the end of soaking. Nixtamal moisture was 47.9% after soaking and only 41.5% at the end of cooking. Cooking time with soaking for 50% moisture in the grain varied from 69 to 122 minutes at 1500 meters over sea level. The cooked grain was dried with hot air and ground however, the particle size obtained was not as that in commercial nixtamalized maize flour. However, the cooking quality parameters to make dough and tortillas were acceptable, with a penetration index of hydrated flour of 178.6 mm, pH 7.97, water absorption index (WAI) of 3.23 g gel/g flour and 4.11% water solubility index (WSI). All flours from the 11 varieties of maize gave acceptable tortillas as evaluated by physical characteristics and sensory quality. However of the 11 varieties 7 including the control were superior for nixtamalization cooking quality.

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