Maçã 'Royal Gala' revestida com quitosana estocada à temperatura ambiente

The aim of this work was to evaluate apples covered with chitosan during storage at ambient temperature. 'Royal Gala' apples were covered with chitosan (MRQ), immersed in acetic acid solution (MB) or did not receive any treatment (MC) and subsequently analyzed physicochemical, sensorial andinstrumentally, as well as for rotten occurrence, at zero, 7, 14, 21, 28, 35, 42 and 46 days of storage. The ratio, pH and reducing sugar contents increased while total titratable acidity, total sugars, total solids and firmness were reduced during storage. Was observed a drastically reduction of ascorbic acid and slight increase on soluble solids, except in the apples that were not pretreated (MC). Luminosity and chromaticity ratio values improved with time, with higher intensity in MRQ. Rotten occurrence was not expressive. The acceptance of appearance, color, global impression, aroma and flavor decreased with time, and appearance and texture were considered the most important sensory attributes for apples. The use of chitosan delayed ripening, reduced losses in firmness and presented a more intense bright, extending shelf life period up to seven days.

Inter-relação entre o balanço cátion-aniônico do alimento e o ph urinário de gatos

Studies for the food development of formulations for pets, look for key components to maintaining healthy way of life and safety of products, including these, elements capable of preventing the risk of certain metabolic disorders associated with diet. Feline urinarytract disorders, highlights the urolithiasis, have high incidence in clinical series. Studies linking dietary factors such as ingredients, digestibility and chemical composition, changing the volume, density and pH of urine and consequent induction training for urolithiasis. A highly significant correlation between the mineral composition of the diet and urine pH of cats began to be studied, using the association between the cation-anion balance of the diet (DCAB) and regulation of acid-base balance of the body. The DCAB can be defined as the difference between the total fixed anions and cations present in the diet, important tool for estimating the urinary pH and to determine the range of pH that favors the food used, thereby linking the trigger and the prevention of struvite and calcium oxalate urolithiasis in the urinary tract of cats. Thus, this review aims to clarify the effects of the nutritional composition of diet on urine pH in cats.

Effect of different radiopacifying agents on the physicochemical properties of white portland cement and white mineral trioxide aggregate

Introduction: The aim of this study was to evaluate the pH, calcium ion release, setting time, and solubility of white mineral trioxide aggregate (WMTA) and white Portland cement (WPC) combined with the following radiopacifying agents: bismuth oxide (BO), calcium tungstate (CT), and zirconium oxide (ZO). Methods: Fifty acrylic teeth with root-end filling material were immersed in ultrapure water for measurement of pH and calcium release (atomic absorption spectrophotometry) at 3, 24, 72, and 168 hours. For evaluation of setting time, each material was analyzed according to the American Society for Testing and Materials guidelines 266/08. The solubility test was performed according to American National Standards Institute/American Dental Association specification no. 57/2000. Solubility, setting time, and pH values were compared by using analysis of variance and Tukey test, and the values of calcium release were compared by the Kruskal-Wallis and Miller tests. The significance level was set at 5%. Results: The pH and calcium release were higher at 3 and 24 hours. WPC was the material with the higher values for both properties. WMTA had the greatest solubility among all materials (P <.05). All radiopacifiers increased the setting time of WPC, and WMTA had the shortest setting time among all materials (P < .05). Conclusions: All materials released calcium ions. Except for WPC/CT at 168 hours, all materials promoted an alkaline pH. On the basis of the obtained results, ZO and CT can be considered as potential radiopacifying agents to be used in combination with Portland cement. Copyright © 2012 American Association of Endodontists.

Acidosis ruminal en bovinos lecheros: Implicaciones sobre la producción y la salud animal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização analítica de sucos e néctares de laranja adoçados com sacarose e edulcorantes

Objective: To characterize physically and chemically, non-sweetened orange juices and orange nectars sweetened with sucrose or sweet flavoring agents, with respect to their pH, titratable acidity (TA) and total soluble solids content (TSSC), as well as to evaluate the correlation of the latter property with the others. Method: Aliquots of three lots of two orange juices and two orange nectars containing sucrose and two containing sweet flavoring agents were evaluated. Mineral water was used as a control. The TSSC was determined using an Abbe refractometer. The pH was recorded using a digital pH meter, while TA was quantified by titrating samples of the beverages with 0.1 M NaOH until reaching pHs 5.5 and 7.0. Data were subjected to Pearson's correlation test, regression analysis, analysis of variance and Tukey's test (α=0.05). Results: TSSC values presented a strong correlation with TA, and these properties exhibited a quadratic relationship. Although the pH values were not dependent on the presence of sucrose or sweet flavoring agents, a significantly greater amount of base was necessary to reach pHs 5.5 and 7.0 in the beverages without sucrose or flavoring agents. Conclusion: Orange juices and nectars presented similar pH values, which was not associated with the presence of sucrose or sweet flavoring agents in the beverages. Higher TA values were obtained for the juice and lower for the nectars, regardless of containing sucrose or sweet flavoring agents. The increase of TSSC did not implicate in decrease of TA in the beverages.

Delineation of specific management areas for coffee cultivation based on the soil-relief relationship and numerical classification

Predicting and mapping productivity areas allows crop producers to improve their planning of agricultural activities. The primary aims of this work were the identification and mapping of specific management areas allowing coffee bean quality to be predicted from soil attributes and their relationships to relief. The study area was located in the Southeast of the Minas Gerais state, Brazil. A grid containing a total of 145 uniformly spaced nodes 50 m apart was established over an area of 31. 7 ha from which samples were collected at depths of 0. 00-0. 20 m in order to determine physical and chemical attributes of the soil. These data were analysed in conjunction with plant attributes including production, proportion of beans retained by different sieves and drink quality. The results of principal component analysis (PCA) in combination with geostatistical data showed the attributes clay content and available iron to be the best choices for identifying four crop production environments. Environment A, which exhibited high clay and available iron contents, and low pH and base saturation, was that providing the highest yield (30. 4l ha-1) and best coffee beverage quality (61 sacks ha-1). Based on the results, we believe that multivariate analysis, geostatistics and the soil-relief relationships contained in the digital elevation model (DEM) can be effectively used in combination for the hybrid mapping of areas of varying suitability for coffee production. © 2012 Springer Science+Business Media New York.

Alkali activated materials based on fluid catalytic cracking catalyst residue (FCC): Influence of SiO2/Na2O and H 2O/FCC ratio on mechanical strength and microstructure

Reuse of industrial and agricultural wastes as supplementary cementitious materials (SCMs) in concrete and mortar productions contribute to sustainable development. In this context, fluid catalytic cracking catalyst residue (spent FCC), a byproduct from the petroleum industry and petrol refineries, have been studied as SCM in blended Portland cement in the last years. Nevertheless, another environmental friendly alternative has been conducted in order to produce alternative binders with low CO2 emissions. The use of aluminosilicate materials in the production of alkali-activated materials (AAMs) is an ongoing research topic which can present low CO2 emissions associated. Hence, this paper studies some variables that can influence the production of AAM based on spent FCC. Specifically, the influence of SiO 2/Na2O molar ratio and the H2O/spent FCC mass ratio on the mechanical strength and microstructure are assessed. Some instrumental techniques, such as SEM, XRD, pH and electrical conductivity measurements, and MIP are performed in order to assess the microstructure of formed alkali-activated binder. Alkali activated mortars with compressive strength up to 80 MPa can be formed after curing for 3 days at 65°C. The research demonstrates the potential of spent FCC to produce alkali-activated cements and the importance of SiO2/Na2O molar ratio and the H2O/spent FCC mass ratio in optimising properties and microstructure. © 2013 Elsevier Ltd. All rights reserved.

Enzyme use in kibble diets formulated with wheat bran for dogs: Effects on processing and digestibility

Recently, there is an interest in technologies that favour the use of coproducts for animal nutrition. The effect of adding two enzyme mixtures in diets for dogs formulated with wheat bran (WB) was evaluated. Two foods with similar compositions were formulated: negative control (NC; without WB) and test diet (25% of WB). The test diet was divided into four treatments: without enzyme (positive control), enzyme mixture 1 (ENZ1; added before extrusion β-glucanase, xylanase, cellulase, glucoamylase, phytase); enzyme mixture 2 (ENZ2; added before extrusion the ENZ1 more α-amylase); enzyme mixture 2 added after the extrusion (ENZ2ex). ENZ1 and ENZ2 were used to evaluate the enzyme effect on extruder pre-conditioner (processing additive) and ENZ2ex to evaluate the effect of enzyme supplementation for the animal. Digestibility was measured through total collection of faeces and urine. The experiment followed a randomized block design with five treatments (diets) and six dogs per diet, totalling 30 dogs (7.0 ± 1.2 years old and 11.0 ± 2.2 kg of body weight). Data were submitted to analysis of variance and means compared by Tukey's test and orthogonal contrasts (p < 0.05). Reducing sugars showed an important reduction after extrusion, suggesting the formation of carbohydrate complexes. The apparent total tract digestibility (ATTD) of dry matter, organic matter, crude protein, acid-hydrolysed fat and energy was higher in NC than in diets with WB (p < 0.001), without effects of enzyme additions. WB diets resulted in higher faecal production and concentration of short-chain fatty acids (SCFA) and reduced pH and ammonia concentration (p < 0.01), with no effect of enzyme addition. The enzyme addition did not result in improved digestibility of a diet high in non-starch polysaccharides; however, only ATTD was measured and nutrient fermentation in the large intestine may have interfered with the results obtained. WB modified fermentation product formation in the colon of dogs. © 2013 Blackwell Verlag GmbH.

Effects of pre-slaughter fasting on broiler welfare, meat quality, and intestinal integrity

The Brazilian Ministry of Agriculture (MAPA) regulations establish 12 hours as the maximum pre-slaughter fasting period for broilers; however, many processing plants have considered this time is not sufficient, and consequently return the birds to the farms, with consequent economic losses and welfare problems. Therefore, it is necessary to investigate the possible effects of longer pre-slaughter fasting times. The objective of the present study was to evaluate the effect of pre-slaughter fasting times longer than those established by MAPA on broiler welfare, breast meat quality, and intestinal integrity. Forty 42-d-old broilers were submitted to different pre-slaughter fasting times: group I: 6 hours, group II 9h, group III 12h, and group IV 15h. Bird welfare was assessed before slaughter. After sacrifice, intestinal samples were collected to assess their morphology and morphometrics, and the Pectoralis major muscle was analyzed for pH and color. There was no influence (p>0.05) of treatments on breast muscle pH or color.There were no significant changes in intestinal morphometrics (p<0.05). Bird behavior was affected (p<0.05), suggesting that welfare was impaired as fasting time increased, but no differences in the analyzed parameters were detected between broilers fasted for 12 or 15 hours. It was concluded that the behavioral differences between birds fasted for 12 and 15 hours are not sufficient to assert that those fasted for 15 hours were in worse welfare conditions.

Fast assembly of non-thiolated DNA on gold surface at lower pH

In a typical protocol for attaching DNA to a gold electrode, thiolated DNA is incubated with the electrode at neutral pH overnight. Here we report fast adsorption of non-thiolated DNA oligomers on gold electrodes at acidic pH (i.e., pH ~3.0). The peak-to-peak potential difference and the redox peak currents in typical cyclic voltammetry of [Fe(CN)6]3- are investigated to monitor the attachment. Compared with incubation at neutral pH, the lower pH can significantly promote the adsorption processes, enabling efficient adsorption even in 30min. The adsorption rate is DNA concentration-dependent, while the ionic strength shows no influence. Moreover, the adsorption is base-discriminative, with a preferred order of A>C≫G, T, which is attributed to the protonation of A and C at low pH and their higher binding affinity to gold surface. The immobilized DNA is functional and can hybridize with its complementary DNA but not a random DNA. This work is promising to provide a useful time-saving strategy for DNA assembly on gold electrodes, allowing fast fabrication of DNA-based biosensors and devices. © 2013 Elsevier Inc.

Tratamento térmico na manutenção da qualidade de lichias armazenadas sob refrigeração

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aspectos sensoriais e físico-químicos de iogurtes de soja com espessantes/estabilizantes à base de fécula de inhame (Dioscorea alata), amido modificado e gelatina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Correlação espacial entre os atributos do solo e o índice espectral de vegetação na cultura de cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do desempenho de um reator anaeróbico compartimentado no tratamento de soro de queijo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aproveitamento de vísceras (não comestíveis) de aves para elaboração de farinha de carne: um perfil comparativo entre frango (Gallus domesticus) e ratitas avestruz (Struthio camellus) e ema (Rhea americana)

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE