952 resultados para Slurries samples
Resumo:
The purpose of this study was to verify and compare the main contamination sources and the hygienic/sanitary conditions of organic honey samples of Apis mellifera from Parana River islands. Thirty-three (33) samples were analyzed between January 2005 and August 2006. Eleven (11) samples were collected by beekeepers and twenty-two (22) samples were collected and processed in accordance with ideal personal hygiene norms and good manufacturing practices. The samples underwent microbiological analysis in search of coliforms at 35 ºC and 45 ºC, as well as fungi enumeration analysis. As for fungi counting, the samples harvested by beekeepers showed values above the maximum established by Resolution nº 15/94 of Common Market Group - Mercosul. The results showed that secondary contamination sources are responsible for the reduction of organic honey quality.
Resumo:
This research was carried out to evaluate the physicochemical composition of organic honey in Paraná River islands, in Porto Brasílio, State of Paraná. Honey was harvested directly from super of the colonies in three apiaries spread in the Floresta and Laranjeira Islands, from August 2005 to August 2006. Twenty-four samples of organic honey produced by Africanized honeybees were evaluated. The following parameters were analyzed: pH, acidity, formol index, hydroxymethylfurfural, ashes, color, electric conductivity and moisture. Three replications per sample were performed for laboratorial analysis, giving the means and standard deviation. Most honey samples were in conformity with the Normative Instruction 11 from October 20, 2000. However, 4.17% were not in accordance with the moisture standards, 8.33% showed high concentrations of hydroxymethylfurfural, thus, totalizing 12.50% of non-complying samples. Nevertheless, 87.50% of the analyzed honey samples are within the standards, being characterized as an organic product of excellent quality, with good commercialization perspectives in the market.
Resumo:
A biosensor was developed for spectrophotometric determination of glucose concentrations in real samples of orange juice energetic drinks, and sport drinks. The biosensor consisted of glucose oxidase (GOD) and horseradish peroxidase (HRP) immobilized onto polyaniline activated with glutaraldehyde (PANIG). Immobilization parameters were optimized for GOD, and maximum immobilization yield was 16% when 5.0 mg of PANIG and 8.9 U prepared in 0.1 mol.L-1 sodium phosphate buffer (pH 7.0) reacted for 60 minutes at 4 °C with gentle stirring. The linear operational range for glucose determination using optimized operational parameters was between 0.05 and 6.0 mg.mL-1 with a very good reproducibility of response. The results obtained in the biosensor were compared with those obtained using free enzymes (commercial kits) and then validated through statistical analysis using the Tukey test (95% confidence interval).
Resumo:
Cassava producers in the region of Marília-São Paulo are integrating their farming activity with beekeeping to diversify their income. The aim of this study was to evaluate the physicochemical and microbiological quality of honey samples produced by Africanized honeybees Apis mellifera from cassava flower in 2008. Analysis were carried out for pH, total soluble solids (TSS), acidity, moisture, reducing and total sugars, apparent sucrose, hydroxymethylfurfural, color, ash, proteins, water insoluble solids, diastasic activity, mineral content, microbiological evaluations, and mineral and hydrocyanic acid (HCN) content. The honey samples showed physicochemical and microbiological characteristics favorable to commercialization, with the exception of apparent sucrose and acidity, which show the need for a narrow focus of attention to the honey maturation degree at the harvest time and more careful monitoring during production and processing. The commercialization of Brazilian cassava honey, still little explored, can be widely spread in the market since the levels of hydrocyanic acid (HCN) showed no consumption risk; in addition the simultaneous production of honey and cassava provides an alternative to family income increase.
Resumo:
Seventy-one samples of sugarcane spirits from small and average size stills produced in the northern and southern Minas Gerais (Brazil) were analyzed for acrolein using HPLC (High Performance Liquid Chromatography). Ethanol and copper concentrations and volatile acidity were also determined according to methods established by the Ministry of Agriculture, Livestock and Supply (MAPA). A total of 9.85% of the samples tested showed levels of acrolein above the legal limits, while the copper concentrations of 21.00% of the samples and the volatile acidity of 8.85% of the samples were higher than the limits established by the Brazilian legislation. The concentration of acrolein varied from 0 to 21.97 mg.100 mL-1 of ethanol. However, no significant difference at 5% of significance was observed between the samples produced in the northern and southern Minas Gerais. The method used for determination of acrolein in sugarcane spirits involved the formation of a derivative with 2,4-dinitrophenylhydrazine (2,4-DNPH) and subsequent analysis by HPLC.
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A test that is rapid, simple, accurate, not expensive, gives rapid results, and is sensitive enough to detect low levels of microorganisms would be the most suitable for food industry routine laboratories, or even for a public health laboratories. A ready-to-use alternative, commercially available method is the PetrifilmTM EB method. The aim of this study was to evaluate whether there is a statistically significant difference between the conventional methods based on Violet Red Bile Glucose Agar and the alternative 3M TM Petrifilm (EB) method for the enumeration of Enterobacteriaceae in poultry carcasses. This study also assessed whether the alternative method showed ability to produce results that were directly proportional to the concentration of the target (approximately 270 colony-forming unit.mL-1). A total of 120 poultry carcasses samples showed a significant difference (p < 0.05) between the populations obtained by the two methods, and the conventional method showed low proportionality between the dilutions. On the other hand, the PetrifilmTM EB quantification system showed the capacity to produce results that are proportional to the concentration of the analyte in samples in the concentration range from 1 to 256 colony-forming unit.mL-1.
Resumo:
This study evaluated the physicochemical properties and protein and mineral content of honey samples from Ceará State, Northeastern Brazil, one of the major honey exporters in the country. Nutritional importance of the minerals detected was also analyzed. Physicochemical properties were examined according to the AOAC and CAC official methods; the protein content was determined using the Bradford method, and the minerals were analyzed by atomic absorption spectrometry. All analyses were performed in triplicate. The levels of macrominerals sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg) varied from 1.80-47.20, 21.30-1513.30, 14.58-304.82, and 2.48-28.33 mg/kg, respectively, and the trace elements iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), selenium (Se), and chromium (Cr) varied from 0.12-8.76, 0.07-1.29, 0.06-1.96, 0.07-1.85 mg/kg, 0.36 × 10-3-62.00 × 10-3 and 22.50 × 10-3-170.33 × 10-3 µg/kg, respectively. Myracrodruon urundeuva honey sample had high contents of macrominerals (Na, K, Ca, and Mg). Protein content of the Anacardium occidentale honey sample was the highest (1121.00 µg/g) among the samples analyzed. Among the minerals detected in the honey samples, K showed the highest concentration, followed by Ca, Na, and Mg. The presence of trace elements can show environmental contamination. The honey samples studied were free of trace elements contamination, except for Mn; the Piptadenia moniliformis was the only honey sample that was in compliance with the law requirements. The variations of the chemical constituents in the honey samples are probably related to differences in the floral origin and mineral and protein contents and confirm the nutritional importance of Ceará State honey.
Resumo:
Pan bread samples available in the Brazilian market were evaluated for their physicochemical and sensory characteristics. Twelve pan breads, seven white and five whole grain breads, were evaluated. Moisture, water activity (Aw), firmness, and color (L*, a*, b*) of the crumb were evaluated on the first, fourth, seventh, and tenth days after purchasing the breads. Specific volume was evaluated on the first day of analysis with averages of 4.72 and 4.70 mL/g for the white and whole grain breads, respectively. The average results on the first day of analysis were: 37.03% and 41.23% moisture, 0.954 and 0.966 Aw, 276.27 and 267.83 gf firmness, 74.73 and 64.45 L* values, 0.37 and 3.85 a* values, and 15.51 and 18.98 b* values for the white and whole grain breads, respectively. The samples showed an increase in firmness, reduction in moisture and Aw, and no color changes over time. A survey conducted prior to the acceptance test showed that the three most important factors influencing purchase were taste (19.6%), tenderness (16.8%), and expiration date of the product (14.3%). The results showed that 37.2% of the panelists preferred white bread, 62.8% preferred bread with fibers, and 82.6% would probably or definitely buy white bread with fibers.
Resumo:
Coal slurry was of vital interest during the last century due to its potential as an alternative fuel where liquid fuels were necessary. Recently, environmental impacts of the traditional fuels, similarities of bio-coal to that of coal, and huge bio-coal supply has attracted the attention to prepare bio-coal slurries as a new fuel. Rudolf Diesel who invented the diesel engine on 1895 was of the opinion that diesel engines are capable to use different kinds of fuels due to the special design. He tried some kind of vegetable oil to operate on his IC engine. Recently, due to high energy density and more environmentally friendly fuel, researchers believe that bio-coal slurries could act as a new alternative fuel in large diesel engines. Loads of research on different kinds of bio-coal slurry were done by the other researchers worldwide and a lot of progress to boost slurry’s quality were achieved recently. The present study aims to achieve the ideal condition of different factors affecting on the quality of bio-coal slurry. One charcoal sample and two kinds of torrefied wood were used to investigate and compare the reaction of various factors. The results show a great gap between the quality of slurries made of different samples and more researches are necessary to fully understand the impact of the different parameter and improving the quality.
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Methods of measuring specific heats of small samples were studied. Three automated methods were explored, two of which have shown promising results. The adiabatic continuous heating method, has provided smooth well behaved data but further work is presently underway to improve on the results obtained so far . The decay method has been success fully implemented demonstrating reasonable agreement with accepted data for a copper test sample.
Resumo:
A study was undertaken' to determine the applicability of gas liquid chromatography to the simultaneous analysis of sugars and sugar phosphates from biological samples. A new method of silylation involving dimethylsulfoxide, hexamethyldisilazane, trimethylchlorosilane and cyclohexane (1:0.2:0.1:1) which rapidly silylated sugars and sugar phosphates was developed. Subsequent chromatography on a 5% SE-52 column gave good resolution of the sugar and sugar phosphate samples. Sugar phosphates decomposed during chromatography and were lost at the 7 x 10-3 ~mole level. Acidic ethanol extraction of yeast samples revealed background contamination from the yeast sample, the culture medium and the silylation reagents which would further limit the level of detection obtainable with the glc for sugars in biological samples to the 3 x 10-4 ~mole level.
Resumo:
A substantial research literature exists regarding the psychopathy construct in forensic populations, but more recently, the construct has been extended to non-clinical populations. The purpose of the present dissertation was to investigate the content and the correlates of the psychopathy construct, with a particular focus on addressing gaps and controversies in the literature. In Study 1, the role of low anxiety in psychopathy was investigated, as some authors have proposed that low anxiety is integral to the psychopathy construct. Participants (n = 346) responded to two self-report psychopathy scales, the SRP-III and the PPI-R, as well as measures of temperament, personality, and antisociality. Of particular interest was the PPI-R Stress Immunity sub scale, which represents low anxiety content. I t was found that Stress Immunity was not correlated with SRP-III psychopathy, nor did it share common personality or temperament correlates or contribute to the prediction of anti sociality. From Study 1, it was concluded that it was unlikely that low anxiety is a central feature of the psychopathy construct. In Study 2, the relationship between SRP-III psychopathy and Ability Emotional Intelligence (Le., Emotional Intelligence measured as an ability, rather than as a self-report personality trait-like characteristic) was investigated, to determine whether psychopathy is be s t seen as a syndrome characterized by emotional deficits or by the ability to skillfully manipulate and prey upon the others' emotions. A negative correlation between the two constructs was found, suggesting that psychopathy is best characterized by deficits in perceiving, facilitating, managing, and understanding emotions. In Study 3, sex differences in the sexual behavior (i.e., promiscuity, age of first sexual behaviors, extradyadic sexual relations) and appearance-related esteem (i.e., body shame,appearance anxiety, self-esteem) correlates of SRP-III psychopathy were investigated. The sexual behavior correlates of psychopathy were quite similar for men and women, but the esteem correlates were very different, such that high psychopathy in men was related to high esteem, whereas high psychopathy in women was generally related to low esteem. This sex difference was difficult to interpret in that it was not mediated by sexual behavior, suggesting that further exploration of this topic is warranted. Together, these three studies contribute to our understanding of non-clinical psychopathy, indicating that low anxiety is likely not part of the construct, that psychopathy is related to low levels of ability in Emotional Intelligence, and that psychopathy is an important predictor of behavior, ability, and beliefs and feelings about the self