Dynamics of the loss and emergence of volatile compounds during the concentration of cashew apple juice (Anacardium occidentale L.) and the impact on juice sensory quality.

Concentrating cashew apple juice alters the beverage aroma and flavor, compromising consumer acceptability of the concentrated beverage. To understand the mechanisms involved in these changes, this research characterized the dynamics of the loss and emergence of volatile compounds during cashew apple juice concentration, reporting their impact on beverage sensory quality. Fresh cashew apple juice (10.3°Brix) was concentrated in a thermal-siphon type evaporator operating in a closed system. Five samples were taken throughout the concentration process with the following soluble solids contents: 11.8°Brix, 14.9°Brix, 20.2°Brix, 29.6°Brix and 42.1°Brix. Trained judges rated the aroma note intensities, described as ?fresh cashew apple? and ?cooked? as perceived in the fresh and concentrated beverages. The headspace volatiles of the six samples were identified and quantified by GC?MS. The results indicated the esters as the major component in the fresh juice (226.46 μg kg− 1) representing 45.0% of the total mass of volatiles, followed by the terpenes (118.98 μg kg− 1), acids (45.23 μg kg− 1), aldehydes (39.10 μg kg− 1), alcohols (18.91 μg kg− 1), lactones (19.15 μg kg− 1), hydrocarbons (18.02 μg kg− 1) and ketones (11.05 μg kg− 1). Predictive statistical models (R2 > 0.956, p ≤ 0.002) revealed that on reaching 14.9°Brix, the ester concentration declined more than 90%, the terpene content almost 100%, alcohols 85%, aldehydes 80% and hydrocarbons 90%. At 14.9°Brix, the intensity of ?fresh cashew apple? aroma still predominated in the juice, but the panelists detected the presence of a weak ?cooked? aroma. Concentration of the beverage to 20.2°Brix or above expressively increased the cooked aroma intensity and the concentration of hydrocarbons, alcohols and some aldehydes usually associated with off-flavors such as pentanal and decanal. This raises the possibility that some of these compounds might have been formed during juice processing. Juice with better sensory quality could possibly be obtained by concentrating the beverage to levels below 20.2°Brix, recovering the esters that evaporated off the juice until ~ 15°Brix is reached, and re-adding them to the juice concentrated

Dynamics of the recovery of aroma volatile compounds during the concentration of cashew apple juice (Anacardium occidentale L.).

The objective of this study was to identify and quantify the recovery of aroma volatiles during the concentration of cashew apple juice and propose kinetic models. Fresh juice was concentrated in a thermal-siphon type evaporator, operating in a closed system at 700 mm Hg. The water and volatiles evaporated during concentration were recovered by condensation, generating five condensates: the first was obtained during the concentration of the juice from 10.6 °Brix (fresh juice) to 12 °Brix, the second from 10.6 to 14 °Brix, the third from 10.6 to 19 °Brix, the fourth from 10.6 to 28 °Brix and the fifth from 10.6 to 40 °Brix. The volatiles in the headspaces of the condensates were vacuum stripped (70 mm Hg) to a Porapak Q? trap for 2 h, eluted with 300 μL of acetone, identified by GC?MS and quantified by external standardization. Trained judges rated the intensity of the cashew apple aroma perceived in the condensates using a 9 cm scale. The major classes of volatiles present in the condensates were esters (~90% of the total mass of volatiles), followed by aldehydes (6%) and alcohols (3%). In the first condensate the ester (580.3 μg L−1), aldehyde (39.3 μg L−1) and alcohol (23.5 μg L−1) concentrations were higher than in the remaining condensates, suggesting that a more efficient recovery of the volatiles important to the cashew apple aroma and flavor could be obtained when the beverage was concentrated from 10.6 to approximately 12 °Brix, namely, by condensing the first 23% of the water evaporated off from the juice. The power function was the kinetic model that best fitted the recovery of the esters, aldehydes and alcohols

Solar radiation use efficiency by soybean under field conditions in the amazon region.

Abstract The objective of this work was to evaluate the ef? ciency of soybean (Glycine max) in intercepting and using solar radiation under natural ? eld conditions, in the Amazon region, Brazil. The meteorological data and the values of soybean growth and leaf area were obtained from an agrometeorological experiment carried out in Paragominas, Pará state, during 2007 and 2008. The radiation use ef? ciency (RUE) was obtained from the ratio between the above-ground biomass production and the intercepted photosynthetically active radiation (PAR) accumulated to 99 and 95 days after sowing, in 2007 and 2008, respectively. Climatic conditions during the experiment were very distinct, with reduction in rainfall in 2007, which began during the soybean mid-cycle, due to the El Niño phenomenon. An important reduction in the leaf area index and biomass production was observed during 2007. Under natural ? eld conditions in the Amazon region, the values of RUE were 1.46 and 1.99 g MJ-1 PAR in the 2007 and 2008 experiments, respectively. The probable reason for the differences found between these years might be associated to the water restriction in 2007 coupled with the higher air temperature and vapor pressure de? cit, and also to the increase in the fraction of diffuse radiation that reached the land surface in 2008. Index terms: Glycine max, Amazon region, leaf area index, radiation interception

Qualidade da carcaça e rendimento de cortes cárneos de machos inteiros e castrados de diferentes grupos genéticos terminados em confinamento.

O experimento objetivou avaliar o desempenho em confinamento e os rendimentos e características das carcaças de bezerros de quatro grupos genéticos submetidos a duas condições sexuais. Bezerros Nelore (NE) e cruzados Canchim x Nelore (CN), Angus x Nelore (AN) e Simental x Nelore (SN), do rebanho da Embrapa Pecuária Sudeste, castrados ou não, após a desmama, recebendo dieta composta por silagem de milho e concentrados. A média de idade no início do confinamento foi de 253 dias e de peso vivo em jejum foram 204; 211 ; 217 e 232 kg para os grupos genéticos NE; CN: AN e SN, respectivamente. A média de ganho de peso foi maior (P0,05) entre condição sexual e grupos genéticos. Não houve interação (P>0,05) entre condição sexual e grupo genético para as características estudadas

Avaliação do sedimento em áreas de produção de peixes em tanques redes no Reservatório de Furnas (MG).

Resumo: A aquicultura tem apresentado um crescimento nos últimos anos consolidando-se como um setor de grande importância econômica. Diante deste crescimento, surge à necessidade de desenvolvimento de processos de monitoramento ambiental que assegurem uma correta interpretação dos possíveis impactos e a melhor forma de diminuí-los. O presente trabalho teve por objetivo avaliar a concentração de metais potencialmente tóxicos e de carbono e nitrogênio, em sedimentos coletados na área de influência direta de piscicultura em tanques rede no reservatório de Furnas. A área de coleta é composta por 4 braços do rio Grande todos no município de Guapé (MG). Em 3 dos 4 braços existem piscicultura em tanques rede e um foi utilizado como controle. Foram realizadas 3 coletas de sedimento em maio, agosto e outubro de 2013, utilizando-se draga de Ekman-Birge. No laboratório, as amostras foram secas, moídas e digeridas para a determinação elementar de Cu (cobre), Pb (chumbo) e Zn (zinco) por Espectrometria de Absorção Atômica com Chama (F-AAS). Os resultados encontrados nas três coletadas variaram de 11,6 a 36,9 mg.L-1 para o Cu, de 95,2 a 184,8 mg.L-1 para o Pb e de 12,7 a 86,3 mg.L-1 para o Zn. O carbono (C) e o nitrogênio (N) total foram determinados por combustão a seco, com resultados que variam de 0,71 a 2,34 % para o C e de 0,097 a 0,224 % para o N. Abstract: Aquaculture has growing in the last decades establishing as sector of great economic importance. The growing of the sector, inputs a necessity to develop environmental monitoring processes to ensuring a correct interpretation of the possible impacts and how the best way to reduce them. This study aimed to evaluate the concentration of potentially toxic metals and carbon and nitrogen in sediments, collected in the area of direct influence of fish farming in tanks, located in Furnas reservoir. The sampling area consists of 4 arms of the rio Grande in the city of Guape (MG). In arms 2 to 4 there are fish farming in net tanks and arm 1 was used as control. Three samples were taken in all sampling sites, during May, August and October 2013, using Ekman-Birge dredge. At the laboratory, samples were dried, ground and digested for elemental determination of Cu (copper), Pb (lead) and Zn (zinc) Spectrometry Flame Atomic Absorption (F-AAS). The results in the three collected ranged from 11.6 to 36.9 mg.L -1 of Cu, 95.2 to 184.8 mg.L -1 for Pb and 12.7 to 86.3 mg.L -1 for Zn. The carbon (C) and nitrogen (N) were determined by the total dry combustion with results ranging from 0.71 to 2.34% for C and 0.097 to 0.224% for

Avaliação dos grânulos de amido em plantas de mandioca (Manihot esculenta Crantz) provenientes de autofecundação.

O amido possui inúmeras aplicações nas indústrias de papel e celulose, petrolífera, mineração, de alimentos, farmacêutica, e outras (CARDOSO & SOUZA, 2002). A indústria modifica o amido, dando-lhe diferentes aplicações. Existe também a possibilidade de a própria planta produzir amido diferenciado. Um exemplo é o amido ceroso ou waxy, descoberto em mandioca em uma planta resultante de autofecundação (CEBALLOS et al., 2007). O amido ceroso distingue-se do comum (nativo) por ter no máximo 5% de amilose, enquanto o amido comum de mandioca tem em torno de 20% de amilose e 80% de amilopectina. Amidos com baixos teores de amilose são importantes, por exemplo, na indústria alimentícia, por não sofrerem retrogradação, isto é, perda de água no processo de aquecimento e resfriamento, e assim, o alimento não endurece, aumentando sua vida de prateleira (MUNHOZ et al., 2004). A mandioca é uma espécie alógama, e por essa razão, espera-se que as plantas sejam heterozigóticas na maioria dos locos. Dessa forma, acredita-se que muitos alelos recessivos responsáveis por características importantes em mandioca estejam em heterozigose, e portanto, sem expressão fenotípica. O amido ceroso, por exemplo, é uma característica controlada por um alelo recessivo (wx), o qual foi exposto à homozigose (wxwx) por meio de uma autofecundação, realizada no Centro Internacional de Agricultura Tropical-CIAT (CEBALLOS et al., 2007). O tamanho dos grânulos de amido é outra característica que influencia suas propriedades físico-químicas, bem como os processos do refinamento (LINDEBOOM et al., 2004). Ceballos et al. (2008) relatam a obtenção de plantas com grânulos pequenos de amido, as quais foram provenientes de irradiação com raios gama, seguida de autofecundação. O objetivo desse trabalho foi testar se a autofecundação pode alterar o tamanho e formato dos grânulos de amido de mandioca