53 resultados para liquid characterization
Resumo:
Food processes must ensure safety and high-quality products for a growing demand consumer creating the need for better knowledge of its unit operations. The Computational Fluid Dynamics (CFD) has been widely used for better understanding the food thermal processes, and it is one of the safest and most frequently used methods for food preservation. However, there is no single study in the literature describing thermal process of liquid foods in a brick shaped package. The present study evaluated such process and the influence of its orientation on the process lethality. It demonstrated the potential of using CFD to evaluate thermal processes of liquid foods and the importance of rheological characterization and convection in thermal processing of liquid foods. It also showed that packaging orientation does not result in different sterilization values during thermal process of the evaluated fluids in the brick shaped package.
Resumo:
Culinary herbs and spices have long been considered essentially as flavor enhancers or preservatives, with little attention given to their potential health-promoting properties. Nevertheless, recent research has shown them to be significant dietary sources of bioactive phenolic compounds. Despite noteworthy efforts performed in recent years to improve our knowledge of their chemical composition, a detailed phenolic profile of these plant-based products is still lacking. In the present work, antioxidant activities and phenolic composition of five herbs and spices, namely caraway, turmeric, dill, marjoram and nutmeg, have been studied. The use of liquid chromatography coupled to LTQ-Orbitrap mass spectrometry enabled the identification of up to 42 phenolic compounds. To the best of our knowledge, two of them, apigenin-C-hexoside-C-pentoside and apigenin-C-hexoside-C-hexoside have not been previously reported in turmeric. Qualitative and quantitative differences were observed in polyphenol profiles, with the highest phenolic content found in caraway. Multivariate statistical treatment of the results allowed the detection of distinctive features among the studied herbs and spices.
Characterization of constituents, quality and stability of pomegranate seed oil (Punica granatum L.)
Resumo:
Abstract This study aimed to characterize pomegranate seed oil and evaluate its quality and stability parameters against those of linseed oil. The profile of fatty acids and phytosterols and the content of tocopherols were analyzed by gas chromatography and high performance liquid chromatography, respectively. The quality of both oils was assessed as recommended by the American Oil Chemists' Society (AOCS) and stability was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching (coupled oxidation of β-carotene/linoleic acid) and Rancimat® assays. While α-linolenic acid (52%) was the most abundant fatty acid in linseed oil (LO), punicic acid (55%) was highest in pomegranate seed oil (PSO). Tocopherols and phytosterols (175 and 539 mg/100 g, respectively) were greater in PSO than in LO (51 and 328 mg/100 g, respectively). Both oils met quality standards. The β-carotene bleaching and the DPPH assays showed greater oxidative stability for PSO than for LO. The Rancimat® method, on the other hand, indicated low stability for both oils.
Resumo:
Fungal diseases are important factors limiting common bean yield. White mold is one of the main diseases caused by soil pathogens. The objective of this study was to quantify the distribution of a fungicide solution sprayed into the canopy of bean plants by spectrophotometry, using a boom sprayer with and without air assistance. The experiment was arranged in a 2 x 2 x 2 factorial (two types of nozzles, two application rates, and air assistance on and off) randomized block design with four replications. Air assistance influenced the deposition of solution on the bean plant and yield increased significantly with the increased rate of application and air assistance in the boom sprayer.
Resumo:
Because of the increasing demand of the industry for the production of essential oils, studies highlight the genetic variability of Piper hispidinervum and P. aduncum species according to their patterns of spatial distribution, showing the Amazon region as the source of superior genetic material in the production of safrole and dillapiole. Thus, the objective this study was to characterize the morphology and the phytochemistry of Piper hispidinervum and P. aduncum populations in the Active Germplasm Bank of Embrapa Acre to generate subsidies for the genetic improvement of these species. The results showed that the average values for leaf width and length were 141.67 and 48.04 mm, and petioles length and diameter measurements were 2.83 and 1.78 mm for P. hispidinervum and 189.22; 67.74; 6.03 and 2.22 mm for P. aduncum respectively. The average height and canopy volume measurements were 2.39 m and 6.30 m3 and 2.70 m and 7.78 m3 respectively for each species. For P. hispidinervum, the population with higher performance indried yield and content of safrole was population 02, with 3.9%, and the population 04 showed 94.3% safrole content, both with genetic material from the region of Acrelândia and Plácido de Castro. To P. aduncum, the populations with better performance were 207, 208 and 209, forming a homogeneous group with dried yield average of 3.8% and dillapiol content of 84-85%. Such populations are indicated for selection in breeding program of these species due to better performance.
Resumo:
Abstract: There is a need for heat tolerant wheat cultivars adapted to the expansion of cultivation areas in warmer regions due to the high demand of this cereal for human consumption. The objective of this study was to evaluate the effect of high temperatures on grain yield and yield components of wheat and characterize heat tolerant wheat genotypes at different development stages. The genotypes were evaluated in the field with and without heat stress. High temperatures reduced the number of spikelets per spike (21%), number of grains per spike (39%), number of grains per spikelet (23%), 1000-grain weight (27%) and grain yield (79%). Cultivars MGS 1 Aliança, Embrapa 42, IAC 24-Tucuruí and IAC 364-Tucuruí III are the most tolerant to heat stress between the stages double ridge and terminal spikelet; MGS 1 Aliança, BRS 264, IAC 24-Tucuruí, IAC 364-Tucuruí III and VI 98053, between meiosis and anthesis; and BRS 254, IAC-24-Tucuruí, IAC-364-Tucuruí III and VI 98053, between anthesis and physiological maturity. High temperatures reduce grain yield and yield components. The number of grains per spike is the most reduced component under heat stress. The genotypes differed in tolerance to heat stress in different developmental stages.
Resumo:
Potassium is a nutrient found at low levels in Brazilian soils, requiring large inputs of fertilizers to achieve satisfactory crop yields. Brazil has high external dependence and limited reserves of soluble K mineral, which is traditionally exploited for the production of fertilizers. On the other hand, it is common the occurrence in the country of potassium-rich silicate minerals which are not commercially exploited. This study aimed to characterize mineralogically and chemically samples of verdete rock separated into size fractions and evaluate its potential as potassium fertilizer. The mineral composition of verdete rock is based on glauconite, quartz and feldspar. The total K2O content in verdete rock ranged from 5.18 to 9.0 dag/kg. The K content extracted in water or 2% citric acid was 2.4% below the total of K, indicating low reactivity of verdete rock and limitations for direct use as K source. The processes of physical fractionation and sedimentation in water are inefficient to promote the concentration of K in the different verdete rock fractions. The total K content in some samples are considerable and may enable the use of this rock as raw material for production of more reactive potassium fertilizers.
Resumo:
The most sold and/or prescribed liquid oral medicines for children in Tubarão, Southern Brazil, were assessed. Their sugar concentration was tested and compared to those in their directions for use. All pharmacies and pediatricians working in the city were visited by a previously trained interviewer. Pre-tested questionnaires were applied in order to assess the most sold pediatric as well as the most prescribed pediatric liquid oral medicines. Three samples of each medicine were analyzed by Lane-Eynon general volumetric method. Among the 14 most sold/prescribed medicines only four did not have sugar contents (analgesic, cortisone, and syrups). Sugar concentration ranged from 8.59 g/100 g of drug (SD=0.29 g/100 g) to 67.0 g/100 g of drug (SD=6.07 g/100 g). Only 50.0% of the total medicines that presented sugar in their ingredients showed this information in their directions.
Resumo:
Metacyclic trypomastigotes ol the CL strain of Trypanosoma cruzi obtained from triatomid vectors and from axenic cultures were comparatively analysed as to their antigen make-up and immunogenic characteristics. They were found to be similar by the various parameters examined. Thus, sera of mice immunized with either one of the two metacyclic types precipitated a 82Kd surface protein from 131I-labeled culture metacyclics. Sera of mice protected against acute T. cruzi infection by immunization with killed culture metacyclics of a different strain (G) recognized, by immunoblotting, a 77Kd protein in both types of CL strain metacyclics. A monoclonal antibody raised against G strain metacyclics, and specific for metacyclic stages of this strain, reacted with both CL strain metacyclic types. Both metacyclic forms were similarly Iysed by various anti-T. cruzi sera, in a complement-mediated reaction.
Resumo:
A total of 138 patients with the age of 4 months to 57 years were attended in different hospitals of São Paulo State with aseptic meningitis. A probable new agent was isolated from the cerebrospinal fluid of 35 of 53 specimens examined. Replication of the agent with similar characteristics was detected by CPE produced in the MDCK cell line. Virus-like particles measuring about 40 nm in diameter were observed by negative staining electron microscopy. No hemaglutinating activity was detected at pH 7.2 by using either human, guinea pig, chicken and at pH ranged 6.0 - 7.2 with goose red blood cells. The agent was not pathogenic to newborn or adult mice. Virus infectivity as measured by CPE was sensitive to chloroform and not inhibited by BuDR, suggesting that agent is an enveloped virus with RNA genome.
Resumo:
Trophozoites from cultures of Entamoeba histolytica strains isolated and grown axenically in Brazil (ICB-CSP, ICB-462 and ICB-32) were used for immune sera production and for characterization of their antigens by using electrophoretic and glycoproteic profiles, in parallel with a standard strain isolated and kept under axenic conditions in USA (HK-9). Hyperimmune sera, presenting high antibody titers with homologous and heterologous antigens, were obtained. The four strains in study revealed similar and complex electrophoretic and glycoproteic profiles showing polypep-tides with molecular weights ranging from 200 to less than 29 kDa. No significant differences were detected between the pathogenic and non-pathogenic strains.
Resumo:
The methanol extract of Leptospira interrogans serovar canicola was purified by precipitation with acetone or acetone and chloroform. The antigenicity of the antigen was not altered by heating or treatment with pepsin and pronase. However the antigenicity was lost when the antigen was treated with periodic acid. Chemical analysis revealed the presence of 40% carbohydrate (22% methylpentose, 28%; hexoses),4% protein, 20% lipid and 2,7% phosphate. The complement fixation test with sera from patients with leptospirosis agreed with the microscopic agglutination reaction.
Resumo:
In this paper the history of 115 recruits that had bathed simultaneously in streams contaminated with Schistosoma mansoni, during military maneuvers, is reported. Thirty four of the infected patients presented the initial phase of the infection diagnosed through epidemiologic, clinical and laboratorial parameters. Three out of the 34 patients did not reveal the clinical picture of the infection, thus being considered representatives of the non-apparent form of the disease. Differences between the intensity of blood eosinophilia, the area of immediate cutaneous reaction and the number of Schistosoma eggs eliminated in the stools proved not to be statistically significant (p>0.05) when the non-apparent and acute cases of schistosomiasis were compared. These cases actually may be considered evidences of the non-apparent form hitherto merely taken for granted in the literature.