ABSTRACT. The aim of this study was to evaluate the phenotypic variation and diversity of cassava for breeding purposes based on the pasting properties of starch, for food applications. The viscosities of the starches, extracted from 1031 accessions, were obtained using a Rapid Visco Analyzer. The best linear unbiased predictors were calculated for five critical points of the viscograms, which were then used to cluster the accessions based on the discriminant analysis of principal components. The wide phenotypic variation identified from the viscograms reveals the high potential for selection gains, especially for pasting temperature and setback. Certain strong correlations indicate that selection based on a specific viscogram trait can be used for indirect selection (e.g., the correlation between peak viscosity and breakdown [0.85]). The lowest Bayesian information criterion identified five different groups. Groups 3 and 4 exhibited high pasting temperatures, while Groups 3 and 5 exhibited low setbacks. Group 3 also exhibited low viscosity and breakdown. However, we focused on selecting cassava accessions with a high pasting temperature and low setback, as these are the most important traits for industrial applications. The predicted genetic gains from the selection of the top 15 cassava accessions for increasing pasting temperature and decreasing setback were 4.40% and 53.17%, respectively. The increased pasting temperature (~72.89°C) and high amplitude of setback (~600 cP) due to selection can guide the utilization of the cassava germplasm for breeding and provide a basis for further studies to develop varieties with added value, especially in the food industry.

Abstract Twenty six sweet cassava clones were evaluated in two agricultural years, in randomized block design, with 3 replications and plots with 25 plants. The harvests were at 12 months after planting, in both years. The traits evaluated were root yield (RY), dry matter content (DMC), total carotenoids content (TC), β-carotene content (BC), trans-β-carotene content (TrBC) and total cyanide content (TCy). Genotype was significant (P<0.05) in all traits. Broad-sense heritability estimates at the plot level ( h m g 2 ) ranged from 77% (RY) to 93% (TC and TrBC), while the accuracy ranged from 0.88 (RY) to 0.96 (BC and TrBC). The genetic correlations among TC, BC and TrBC were high (0.96 to 0.99) and significant, and the genetic correlations involving these traits and TCy were negative. These results demonstrate the existence of great genetic variability in characteristics important to cassava biofortification and, consequently, great perspectives in the breeding for this purpose.

RESUMO O objetivo desse trabalho foi avaliar desempenho agronômico, tempo de cozimento e conservação pós-colheita de raízes de clones de mandioca de mesa, para selecionar aqueles superiores à testemunha Manteiga, na região do Baixo Sul do estado da Bahia. O delineamento foi em blocos casualizados e em esquema de parcelas subdivididas, com três repetições. Onze clones foram avaliados aos 10 e 12 meses após o plantio. Na média das duas colheitas, BRS Kiriris e Saracura tiveram produção total de raízes (39,85 e 33,91 t ha−1, respectivamente) e produção de raízes comerciais (26,54 e 26,71 t ha−1) superiores, comparados ao Manteiga (produção total de raízes: 28,06 t ha−1, produção de raízes comerciais: 16,95 t ha−1). Entretanto, ambos tiveram tempo de cozimento (26,76 e 28,30 min, respectivamente) maiores que o do Manteiga (23,89 min), e BRS Kiriris foi instável com relação à porcentagem de cozimento entre 10 (91,67%) e 12 meses (50%). BRS Aipim Brasil, 2003 14-11, BRS Kiriris, Eucalipto, Saracura e Manteiga foram mais tolerantes à deterioração fisiológica de pós-colheita. Embora alguns dos clones avaliados tenham apresentado bom desempenho nas características avaliadas, analisando-se o conjunto de características, nenhum deles apresenta superioridade suficiente para ser indicado como um potencial substituto do Manteiga, cultivado na região do Baixo Sul do estado da Bahia.

ABSTRACT The objective of this work was to evaluate the agronomic performance, cooking time and postharvest conservation of roots of sweet cassava clones, to select those superior to the Manteiga variety control, in the Baixo Sul region of Bahia state. A randomized block design in split plot scheme, with three replications was used. Eleven genotypes were evaluated at 10 and 12 months after planting. Considering the mean of two harvests, BRS Kiriris and Saracura showed total root yield (39.85 and 33.91 t ha−1, respectively) and commercial root yield (26.54 and 26.71 t ha−1) that are higher compared to Manteiga (total root yield: 28.06 t ha−1, commercial root yield: 16.95 t ha−1). However, both had cooking time (26.76 and 28.30 min, respectively) higher than that of Manteiga (23.89 min), and BRS Kiriris was unstable regarding the cooking percentage between 10 (91.67%) and 12 months (50%). BRS Aipim Brasil, 2003 14-11, BRS Kiriris, Eucalipto, Saracura and Manteiga were more tolerant to postharvest physiological deterioration. Although some of the evaluated clones presented good performance in the evaluated traits, by analyzing the set of traits, none of them shows sufficient superiority to be indicated as a potential substitute for Manteiga, grown in the Baixo Sul region of Bahia state.

Resumo: O objetivo deste trabalho foi selecionar genótipos de mandioca (Manihot esculenta) do banco de germoplasma brasileiro com funcionalidade semelhante à do amido ceroso. Um total de 881 genótipos foi pré-selecionado por análise de componentes principais e agrupamento hierárquico, e seu potencial industrial foi comparado ao dos clones 7745-5WX de mandioca cerosa e WX-Maize de milho ceroso, ambos usados como referência. Dois genótipos se destacaram: BGM0036 e BGM0083. Amostras desses quatro genótipos foram caracterizadas por meio de teor de amilose, microscopia eletrônica de varredura, difração de raios-X, calorimetria diferencial de varredura, viscosidade de pasta e distribuição da cadeia de amilopectina. As amostras apresentaram cristalinidade tipo A e nenhuma diferença estatística (p> 0,05) quanto ao grau de cristalinidade (25,3 a 30,0), o que mostra proporções similares das frações de amilose/amilopectina. Não foram observadas diferenças na microestrutura dos amidos de mandioca. A temperatura inicial de gelatinização e as cadeias curtas de amilopectina apresentaram correlação negativa muito forte, o que indica que uma menor proporção de cadeias curtas de amilopectina resulta em uma maior temperatura inicial de gelatinização. BGM0036 e BGM0083 apresentam baixa viscosidade final, próxima às dos amidos de milho e mandioca cerosos, sendo uma alternativa para a utilização em diferentes alimentos que necessitam de estabilidade durante o congelamento.

Abstract: The objective of this work was to select cassava (Manihot esculenta) genotypes from the Brazilian germplasm bank with a functionality similar to that of waxy starch. A total of 881 genotypes were pre-selected using principal component analysis and hierarchical clustering, and their industrial potential was compared with that of the 7745-5WX waxy cassava and the WX-Maize waxy maize clones, both used as references. Two genotypes stood out: BGM0036 and BGM0083. Samples from these four genotypes were characterized by means of amylose content, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, paste viscosity, and chain-length distribution of amylopectin. The samples presented A-type crystallinity and no statistical differences (p > 0.05) regarding crystallinity degree (25.3 to 30.0), which shows similar proportions of the amylose/amylopectin fractions. No differences were observed in the microstructure of the cassava starches. Initial gelatinization temperature and amylopectin short chains presented a very strong negative correlation, indicating that a lower proportion of short chains of amylopectin results in a higher initial temperature of gelatinization. BGM0036 and BGM0083 show a low final viscosity, close to that of the waxy maize and cassava starches, being an alternative for use in different foods that require stability during freezing.

Resumo A mandioca de mesa pode ser comercializada congelada para facilitar o preparo e o consumo. Este trabalho teve como objetivo avaliar as características físico-químicas, o tempo de cozimento, a qualidade microbiológica e os atributos sensoriais das variedades BRS Aipim Brasil e Eucalipto, durante o armazenamento sob congelamento. As raízes foram lavadas em água, sanitizadas, cortadas em cilindros, descascadas, sanitizadas, drenadas, acondicionadas em embalagens de nylon/ polietileno de baixa densidade e armazenadas a -18 °C, sendo avaliadas a cada 30 dias, aproximadamente. A variedade Eucalipto apresentou a menor umidade (61,98%) e os maiores rendimentos de polpa (71,41%) e teor de amido (33,45%). A variedade BRS Aipim Brasil apresentou menor intensidade de cor (11,48) e maior ângulo de cor (97,45°). Os dois genótipos de mandioca não apresentaram diferenças em termos de acidez, luminosidade, sólidos solúveis, teor de açúcar total e pH. A variedade Eucalipto apresentou o menor tempo de cozimento (25 minutos) e umidade (62,92%), para os cinco tempos de armazenamento avaliados. Essa variedade também apresentou o maior teor de amido durante o armazenamento, exceto aos 31 dias. A variedade Eucalipto foi mais aceita para os atributos cor, aroma e impressão global. Em relação ao sabor e à textura, as duas variedades foram consideradas semelhantes e foram classificadas entre os termos hedônicos “gostei ligeiramente” e “gostei moderadamente”. A aceitação sensorial das raízes não foi alterada ao longo do armazenamento e as notas atribuídas foram acima de 6,0, o que representa o limite mínimo de aceitação, para todos os atributos avaliados. A mandioca congelada a -18 °C pode ser comercializada por 120 dias com segurança microbiológica, sem que ocorram alterações significativas das suas características físico-químicas e sensoriais.

Abstract Sweet cassava can be sold frozen, i.e., frozen food, to facilitate preparation and consumption. This study aimed to evaluate physical-chemical characteristics, cooking time, microbiological quality and sensory attributes regarding the varieties BRS Aipim Brasil and Eucalipto in frozen storage. The roots were washed in water, sanitized, cut into cylinders, peeled, sanitized, drained, packed in nylon/ low density polyethylene packages and stored at -18 °C, being evaluated every 30 days, approximately. The Eucalipto variety showed the lowest moisture (61.98%) and the highest pulp yield (71.41%) and starch content (33.45%). However, the BRS Aipim Brasil variety had lower color intensity (11.48) and greater color angle (97.45°) than Eucalipto. The two cassava genotypes showed no difference in terms of acidity, luminosity, soluble solids, total sugar content and pH. The Eucalipto variety showed the shortest cooking time (25 minutes) and moisture (62.92%) concerning the five storage times that were evaluated. This variety also had the highest starch content during storage, except at 31 days. The Eucalipto variety was more accepted for the color, aroma and overall impression attributes. Regarding flavor and texture, the two varieties were considered similar and were classified between the hedonic terms “like slightly” and “like moderately”. The sensory acceptance of the roots was not altered during storage and the grades attributed were above 6.0, which represents the minimum acceptance limit, for all evaluated attributes. Cassava frozen at -18 °C can be marketed for 120 days without microbiological risk, and without significant changes in its physical-chemical and sensory characteristics.

Resumo O sistema de revestimento não-aderido (RNA) influencia o desempenho da fachada dos edifícios, pois impacta na durabilidade, estanqueidade à agua, estética e valorização do imóvel. O RNA, também denominado pelo mercado como fachada ventilada, é frequentemente utilizado em fachadas de edifícios residenciais, comerciais, novas construções, renovações ou retrofit, considerado também uma forma eficiente de reduzir os problemas de umidade da fachada. Entretanto, a ausência de normalização técnica específica limita o crescimento do uso desta tecnologia no Brasil. Além disso, no Brasil, existe a NBR 15575, partes 1-6 (2013), que estabelece critérios de desempenho, bem como os respectivos métodos de avaliação para avaliar os principais sistemas do edifício: estrutura, piso, vedações verticais, cobertura e instalações. Entretanto, esta norma pode somente ser parcialmente adotada para o RNA, pois a NBR apresenta critérios considerando toda a fachada e, não somente, o revestimento. No presente artigo são propostos critérios de desempenho e métodos de ensaio aplicados para RNA, particularmente abordando os requisitos de segurança estrutural (resistência a cargas de vento, e a impactos de corpo mole e corpo duro) e drenabilidade. Para este estudo, as seguintes atividades foram realizadas: revisão bibliográfica, estudo de caso e ensaios em protótipo para validar a proposta de critérios e métodos de ensaios.

Abstract Cladding systems have significant effect on the performance and durability of building façades, contributing to the building watertightness, property valuation, aesthetic finishing, and decoration. Non-adherent cladding, also named rainscreen cladding or ventilated cladding, is currently used in residential and commercial buildings, new constructions, or retrofit operations, and it is considered an efficient measure to improve the moisture safety of building envelopes. Therefore, the absence of Brazilian normalization to ventilated cladding systems is one of the difficulties limiting its increased local application. In Brazil, a technical standard, NBR 15575, parts 1-6, (2013), establish the general performance requirements and test methods to evaluate residential building systems including structure, wall, floor, coverage, and hydraulic installation. However, this standard cannot be integrally applied to the cladding systems because it was developed considering the vertical wall system as a whole. In this study, we propose the criteria and test methods for assessing ventilated cladding systems while taking into account the structural safety (wind loads resistance, hard and soft impact resistance) and drainability requirements. The following activities are performed: literature review, practical case study, and tests on prototypes for validation of the proposal. The tests allow verification of the feasibility of the criteria and tests methods proposed. In addition, the proposal makes it possible to guide design, construction, and maintenance needs, thereby inducing the growth of this technology in Brazil.

RESUMO: A cultura da banana tem baixa diversidade genética, tornando a espécie susceptível a doenças dizimadoras como a Sigatoka negra. No entanto, a adoção de novas variedades necessita de avaliações agronômicas e físico-químicas. Neste estudo, as variedades de banana, resistentes à Sigatoka negra, foram caracterizadas e comparadas com a variedade tradicional (Grand Naine). Cada variedade foi avaliada considerando-se critérios relevantes para a agroindústria, como pH, sólidos solúveis totais, acidez total titulável, relação SST/ATT, açúcares totais, açúcares redutores e não redutores, umidade, sólidos totais e rendimento no processamento. A variedade Thap Maeo apresentou-se como a variedade mais potencial para substituição da Gran Naine na indústria, com altos teores de sólidos solúveis totais, açúcares redutores, açúcares totais e umidade. As variedades Caipira e FHIA 2 também podem substituir a Grand Naine. Na análise de agrupamentos, verificou-se que a variedade Grand Naine esteve muito próxima das variedades do subgrupo Gros Michel (Bucaneiro, Ambroisa e Calipso) e também da variedade Caipira, apresentando no seu genoma o grupo AAA. Conclui-se que há opções de variedades resistentes para substituição da variedade tradicional, nas regiões afetadas pela Sigatoka-negra.

ABSTRACT: Cultivated bananas have very low genetic diversity making them vulnerable to diseases such as black-Sigatoka leaf spot. However, the decision to adopt a new banana variety needs to be based on a robust evaluation of agronomical and physical-chemical characteristics. Here, we characterize new banana varieties resistant to black-Sigatoka leaf spot and compare them to the most widely used traditional variety (Grand Naine). Each variety was evaluated for a range of physic-chemical attributes associated with industrial processing and flavor: pH, TTA, TSS/TTA, total sugars, reducing sugars and non-reducing sugars, humidity, total solids and yield. The Thap Maeo variety had the highest potential as a substitute for the Grand Naine variety, having higher levels of total soluble solids, reducing sugars, total sugars and humidity. The Caipira and FHIA 2 varieties also performed well in comparison with the Grand Naine variety. Cluster analysis indicated that the Grand Naine variety was closely associated with varieties from the Gross Michel subgroup (Bucaneiro, Ambrosia and Calipso) and the Caipira variety, all of which come from the same AAA genomic group. It was concluded that several of the new resistant varieties could potentially substitute the traditional variety in areas affected by black-Sigatoka leaf spot disease.

The conservation, sustainable evaluation and use of cassava (Manihot esculenta Crantz) genetic resources are essential to the development of new commercial varieties. This study aimed to evaluate the quality of cassava roots and to estimate genetic variation and clustering in cassava germplasm using the Affinity Propagation algorithm (AP), which is based on the concept of "message passing" between data points. AP finds "exemplars" of each group and members of the input set representative of clusters. The genotypic data of 474 cassava accessions were evaluated over a period of two years for starch yield (StYi), root dry matter (DMC), amylose content (AML), and the level of cyanogenic compounds (CyC). The AP algorithm enabled the formation of nine diversity groups, whose number reflects the high genetic diversity of this germplasm. A high homogeneity of genetic distances was observed within all the groups, except for two groups in which there was a partial overlap caused mainly by a high variation of the CyC trait. In addition, no relationship between the genetic structure and CyC (sweet and bitter cassava) was observed. Analysis of variance of the nine clusters confirmed the presence of differences between the groups. Thus, the results of this study can be used in future breeding programs (hybridization or selection) to introduce new genetic variability into commercial cultivars to avoid problems related to low genetic variation and to improve the quality of cassava roots.

A partição de duas proteínas, albumina de soro bovino (BSA) e tripsina foi estudada no sistema bifásico aquoso Polietileno glicol(PEG) - Goma do cajueiro. O diagrama de fases foi estabelecido para a Goma do Cajueiro e para PEG de peso molecular 1500 em duas diferentes temperaturas. A influência de vários parâmetros na partição destas proteínas, incluindo concentração dos polímeros, pH, adição de sal e temperatura foi investigada. Os resultados desta pesquisa demonstraram a importância das características da proteína na partição em sistemas bifásicos aquosos.

The partitioning of two proteins, bovine serum albumin (BSA) and trypsin was studied in an aqueous poly(ethylene glycol)(PEG)- Cashew-nut tree gum system. The phase diagram was provided for Cashew-nut tree gum and PEG molecular weight of 1500 at two different temperatures. The influence of several parameters including concentrations of polymers, pH, salt addition and temperature on the partitioning of these proteins were investigated.. The results of this research demonstrated the importance of the protein characteristics for partitioning in aqueous biphasic system.