COMPARAÇÃO DAS PROPRIEDADES REOLÓGICAS DA MASSA DE CACAU TORRADA CONVENCIONALMENTE E POR MICROONDAS

Two kinds of roasting cocoa system: conventional batch method in electrical oven, and by microwaves, in a continuous microwave rotary applicator (2450MHz), were compared with respect to viscosity. Cocoa was roasted in whole beans and in nibs. The variable used in the microwave treatment was the power density applied to the whole beans (254,45 to 290,80 Wh/kg) and to the nibs (227,27 to 262,23 Wh/kg), with a constant holding time of 10 minutes. The variable used in the conventional roasting process was the roasting time of the beans (40 to 44 min) and the nibs (34 to 38 min), with constant temperature in the jacket of electric oven (150°C). Viscosity was measured in a Brookfield rheometer (mod RV-DVIII) at 40°C. In general, the plastic viscosity of the microwaved samples was lower than that of the conventional roasted samples. Also the nibs showed lower viscosities than the whole beans when roasted in the electric oven. The viscosity of the samples roasted in the microwave oven was lower in the whole beans than in the nibs. The product was sensorially evaluated by three experts in cocoa flavour, and it was shown that the flavour of the microwave roasted products was similar to that of the conventionally roasted products, with the advantage of a reduction in process time.

Sensory evaluation of black instant coffee beverage with some volatile compounds present in aromatic oil from roasted coffee

The oil obtained from Brazilian roasted coffee by supercritical CO2 extraction shows considerable aromatic properties, mainly composed by five aromatic compounds, 2-methylpyrazine; 2-furfurylalcohol, 2,5-dimethylpyrazine; γ-butyrolactone and 2-furfurylacetate. Sensory analyses were used to verify the influence of a mixture of these important classes of aromatic coffee compounds (pyrazines, furans and lactones) and of the roasted coffee aromatic oil on the coffee aroma and flavour of black instant freeze and spray-dried coffee beverages. In the acceptance evaluation of the aroma, the samples prepared with freeze-dried instant coffee without the mixture of volatile compounds (sample 4) were not significantly different from the freeze-dried instant coffee in which the aromatic coffee oil was added (sample 5) and from the sample prepared with freeze-dried coffee in which the mixture of the five volatile was added (sample 3), coincidentally from the same drying process. Therefore, sample (3) did not differ from samples prepared with spray dried instant coffee without (sample 1) and to which (sample 2) the mixture of volatile was added. Therefore, with respect to this attribute, the addition of this mixture did not interfere in this drink acceptance. Taking into consideration the flavor, samples prepared with freeze-dried instant coffee in which the aromatic coffee oil was added (5) and the samples with (3) and without (4) the mixture of the five volatile was added did not differ significantly, however sample (4) did not differ from samples (1) and (2). Regarding this attribute, the addition of the aromatic oil of roasted coffee or a mixture of volatile in samples of freeze-dried instant coffee had a better acceptance than those dried by spray dryer (1) and (2). Thus, the enrichment of drinks with the aromatic oil of roasted coffee, or even with the mixture of the five components did not influence the consumer acceptance with respect to the aroma, but exerts influence with respect to flavour.

Quality and sensorial characteristics of osmotically dehydrated mango with syrups of inverted sugar and sucrose

Osmotic dehydration is becoming more popular as a complementary treatment in the processing of dehydrated foods, since it presents some advantages such as minimising heat damage to the colour and flavour, inhibiting enzymatic browning and thus dispensing the addition of sulphite and, mainly, reducing energy costs. The objective of the present study was to evaluate the effect of using inverted sugar and sucrose syrups as osmotic agents in the dehydration of mango. The conditions used in the dehydration process were: syrup/fruit ratio of 3:1 (v/w); temperature of 45ºC and constant stirring. The in natura and osmo-dehydrated fruits were evaluated in relation to pH, moisture content, water activity (a w) and soluble solids (ºBrix). Solids incorporation and loss in mass after the dehydration process were also determined. The sensory acceptance of the in natura and osmo-dehydrated fruits was determined for the attributes of aroma, flavour, texture and overall acceptance using a hedonic scale. Osmotic dehydration resulted in a reduction in moisture content and water activity, an increase in Brix and maintenance of the pH. The treatment with inverted sugar syrup resulted in more significant alterations in moisture content, a w, Brix, solids incorporation and loss in mass than the treatment with sucrose syrup. Mangos osmo-dehydrated with inverted sugar (55.3% inversion rate) syrup obtained acceptance similar to in natura mangos, this treatment being considered the most adequate for dehydration purposes.

Tubo de ácido poliglicólico e GM1 na regeneração de nervos periféricos

INTRODUÇÃO: A auto-enxertia de nervo é considerada tratamento de escolha nas grandes perdas de tecido neural que não permitam a reparação através de anastomose primária. Nesses casos, o tubo sintético à base de ácido poliglicólico é uma alternativa para enxertia de nervo. Por outro lado, muitos estudos têm enfatizado a importância dos fatores neurotróficos na regeneração neural: o monossialotetraesosilgangliosídeo (GM1), um dos principais glicoesfingolípides do tecido nervoso de mamíferos, é tido como potencializador dos efeitos desses fatores. OBJETIVO: Comparar, em ratos, o grau de regeneração neural, utilizando análise histológica, contagem do número de axônios mielinizados regenerados e análise funcional com a utilização do neurotubo e do GM1. MÉTODOS: Essa avaliação foi obtida com a interposição de enxerto autógeno (grupo A), tubo de ácido poliglicólico (grupo B) e da associação do tubo de ácido poliglicólico à administração de GM1 (grupo C) em defeitos de 5 mm no nervo ciático. RESULTADOS: Foi observada formação de neuroma apenas no grupo A. Os grupos A e C apresentaram padrões histológicos semelhantes, exceto que os axônios regenerados do grupo C apresentavam-se mais organizados e mielinizados que o grupo A. CONCLUSÃO: Na recuperação funcional, não houve diferença estatisticamente significativa entre os três grupos, a despeito das diferenças histológicas qualitativas e quantitativas verificadas.

Effect of fructans-based fat replacer on chemical composition, starch digestibility and sensory acceptability of corn snacks

To develop a convenience healthy food snack the partially hydrogenated vegetable fat, used as the flavour fixative agent, was replaced by a non-fat-flavouring solution enriched with inulin and oligofructose. The effects of this replacement on chemical composition, in vitro rate of starch digestion and sensory acceptability were assessed. The new snack presented low-fat levels (0.1 per cent) and around a sevenfold increase in dietary fibre (15.3 per cent of dietary fibre, being 13.3 per cent of fructans) when compared with the traditional ones. The enrichment with fructans reduced the predicted Glycaemic Index by 25 per cent, thus indicating that this dietary fibre contributes effectively towards delaying the in vitro glycaemic response. Fructans-enriched snack presented overall acceptability score (6.6 ± 1.7) similar to the traditional one, flavoured with fatty fixative agent (7.4 ± 1.4). The healthy low-fat fibre-enriched snack produced presented the high sensory acceptability typical for this food product type

Optimization of the Enzymatic Interesterification of Milk Fat and Canola Oil Blends Using Immobilized Rhizopus oryzae Lipase by Response Surface Methodology

Blends of milk fat and canola oil (MF:CNO) were enzymatically interesterified (EIE) by Rhizopus oryzne lipase immobilized on polysiloxane-polyvinyl alcohol (SiO(2)-PVA) composite, in a solvent-free system. A central composite design (CCD) was used to optimize the reaction, considering the effects of different mass fractions of binary blends of MF:CNO (50:50, 65:35 and 80:20) and temperatures (45, 55 and 65 degrees C) on the composition and texture properties of the interesterified products, taking the interesterification degree (ID) and consistency (at 10 degrees C) as response variables. For the ID variable both mass fraction of milk fat in the blend and temperature were found to be significant, while for the consistency only mass fraction of milk fat was significant. Empiric models for ID and consistency were obtained that allowed establishing the best interesterification conditions: blend with 65 % of milk fat and 35 %, of canola oil, and temperature of 45 degrees C. Under these conditions, the ID was 19.77 %) and the consistency at 10 degrees C was 56 290 Pa. The potential of this eco-friendly process demonstrated that a product could be obtained with the desirable milk fat flavour and better spreadability under refrigerated conditions.

Functional characterization of the sciarid BhC4-1 core promoter in transgenic Drosophila

Background: Core promoters are cis-regulatory modules to which bind the basal transcriptional machinery and which participate in the regulation of transcription initiation. Although core promoters have not been extensively investigated through functional assays in a chromosomal context, the available data suggested that the response of a given core promoter might vary depending on the promoter context. Previous studies suggest that a (-57/+40) fragment constitutes the core promoter of the BhC4-1 gene which is located in DNA puff C4 of the sciarid fly Bradysia hygida. Here we tested this (-57/+40) fragment in distinct regulatory contexts in order to verify if promoter context affects its core promoter activity. Results: Consistent with the activity of a core promoter, we showed that in the absence of upstream regulatory sequences the (-57/+40) fragment drives low levels of reporter gene mRNA expression throughout development in transgenic Drosophila. By assaying the (-57/+40) fragment in two distinct regulatory contexts, either downstream of the previously characterized Fbp1 enhancer or downstream of the UAS element, we showed that the BhC4-1 core promoter drives regulated transcription in both the germline and in various tissues throughout development. Furthermore, the use of the BhC4-1 core promoter in a UAS construct significantly reduced salivary gland ectopic expression in third instar larvae, which was previously described to occur in the context of the GAL4/UAS system. Conclusions: Our results from functional analysis in transgenic Drosophila show that the BhC4-1 core promoter drives gene expression regardless of the promoter context that was assayed. New insights into the functioning of the GAL4/UAS system in Drosophila were obtained, indicating that the presence of the SV40 sequence in the 3' UTR of a UAS construct does not preclude expression in the germline. Furthermore, our analysis indicated that ectopic salivary gland expression in the GAL4/UAS system does not depend only on sequences present in the GAL4 construct, but can also be affected by the core promoter sequences in the UAS construct. In this context, we propose that the sciarid BhC4-1 core promoter constitutes a valuable core promoter which can be employed in functional assays in insects.

The CEBPA gene is down-regulated in acute promyelocytic leukemia and its upstream promoter, but not the core promoter, is highly methylated

impairment of CCAAT Enhancer Binding Protein alpha (CEBPA) function is a common finding in acute myeloid leukemia; nevertheless, its relevance for acute promyelocytic leukemia pathogenesis is unclear. We analyzed the expression and assessed the methylation status of the core and upstream promoters of CEBPA in acute promyelocytic leukemia at diagnosis. Patients with acute promyelocytic leukemia (n=18) presented lower levels of CEBPA expression compared to healthy controls (n=5), but higher levels than those in acute myeloid leukemia with t(8;21) (n=9) and with inv(16) (n=5). Regarding the core promoter, we detected no methylation in 39 acute promyelocytic leukemia samples or in 8 samples from controls. In contrast, analysis of the upstream promoter showed methylation in 37 of 39 samples, with 17 patients showing methylation levels over 30%. Our results corroborate data obtained in animal models showing that CEBPA is down-regulated in acute promyelocytic leukemia stem cells and suggest that epigenetic mechanisms may be involved.

Wine industry residues extracts as natural antioxidants in raw and cooked chicken meat during frozen storage

The effect of Isabel (IGE) and Niagara (NGE) grape seed and peel extracts on lipid oxidation, instrumental colour, pH and sensory properties of raw and cooked processed chicken meat stored at -18 degrees C for nine months was evaluated. The pH of raw and cooked samples was not affected by the addition of grape extracts. IGE and NGE were effective in inhibiting the lipid oxidation of raw and cooked chicken meat, with results comparable to synthetic antioxidants. The extracts caused alterations in colour, as evidenced by the instrumental (darkening and lower intensity of red and yellow colour) and sensory results of cooked samples. In the sensory evaluation of odour and flavour, IGE produced satisfactory results, which did not differ from synthetic antioxidants. These findings suggest that the ICE and NGE are effective in retarding lipid oxidation of raw and cooked chicken meat during frozen storage. (c) 2011 Elsevier Ltd. All rights reserved.

Microencapsulation of propolis extract by complex coacervation

The propolis has potential to be a natural food additive However its application is limited because It is alcohol-soluble and has strong flavour Microencapsulation may be an alternative for reducing these problems The aim of this study was to encapsulate propolis extract by complex coacervation using isolated soy protein and pectin as encapsulant agents The coacervation was studied as a function of pH (5 0 4 5 4 0 and 3 5) and the concentration of encapsulants and core (2 5 and 5 0 g/100 mL) Samples obtained at pH 4 0 in both concentrations were lyophilized and analyzed for hygroscopicity encapsulation efficiency particle size morphology thermal behavior stability of phenolic and flavonoids during storage as well as antioxidant and antimicrobial activities It was possible to encapsulate propolis extract by complex coacervation and to obtain it in the form of powder alcohol-free stable with antioxidant property antimicrobial activity against Staphylococcus aureus and with the possibility of controlled release in foods (C) 2010 Elsevier Ltd All rights reserved

MORTADELLA SAUSAGE PRODUCED WITH SOYBEAN OIL INSTEAD OF PORK FAT

This study examines the effects of partially or completely replacing pork backfat with soybean oil in mortadella production. Mortadella sausages of various formulations showed no differences (P > 0.05) in any of the technological and physico-chemical parameters evaluated (process yield, shear force, pH, water activity and proximate composition). When compared to products made with pork backfat, those made with vegetable oil had a higher unsaturated fatty acid content (P <= 0.05) and a similar cholesterol content (P > 0.05). Products made with vegetable oil scored lower (P <= 0.05) than those made with pork fat on all of the evaluated sensory attributes (colour, odour, flavour, texture and overall acceptability).

Cloning, characterization and functional analysis of a 1-FEH cDNA from Vernonia herbacea (Vell.) Rusby

Variations in the inulin contents have been detected in rhizophores of Vernonia herbacea during the phenological cycle. These variations indicate the occurrence of active inulin synthesis and depolymerization throughout the cycle and a role for this carbohydrate as a reserve compound. 1-Fructan exohydrolase (1-FEH) is the enzyme responsible for inulin depolymerization, and its activity has been detected in rhizophores of sprouting plants. Defoliation and low temperature are enhancer conditions of this 1-FEH activity. The aim of the present work was the cloning of this enzyme. Rhizophores were collected from plants induced to sprout, followed by storage at 5C. A full length 1-FEH cDNA sequence was obtained by PCR and inverse PCR techniques, and expressed in Pichia pastoris. Cold storage enhances FEH gene expression. Vh1-FEH was shown to be a functional 1-FEH, hydrolyzing predominantly -2,1 linkages, sharing high identity with chicory FEH sequences, and its activity was inhibited by 81 in the presence of 10 mM sucrose. In V. herbacea, low temperature and sucrose play a role in the control of fructan degradation. This is the first study concerning the cloning and functional analysis of a 1-FEH cDNA of a native species from the Brazilian Cerrado. Results will contribute to understanding the role of fructans in the establishment of a very successful fructan flora of the Brazilian Cerrado, subjected to water limitation and low temperature during winter.

Synergism between lipoxygenase-active soybean flour and ascorbic acid on rheological and sensory properties of wheat bread

BACKGROUND: The interaction between lipoxygenase-active soybean flour (LOX) and ascorbic acid (AA), on colour, rheological and sensory properties of wheat bread was studied with the aim of reducing the applied quantity of additives in bread formulations. RESULTS: The ascorbic acid (0-500 ppm) and active soybean flour (0-1%) mixture improved bread-crumb colour by lowering the yellow hue in a higher proportion than those expressed by the components alone, characterising a synergistic mechanism ((y) over cap (b) = 15.1- (1.7 x LOX) - (0.5 x AA) - (5.8 x LOX x AA), where : (y) over cap (b) represent the estimated value for the yellow hue parameter). No differences in flavour and porosity were seen between the samples. As supported by the instrumental methods, breads made with active soybean flour and ascorbic acid (LOX + AA) had whiter crumbs and were softer and springier than controls as assessed by a trained sensory panel. In summary, the combination of both active soybean flour and ascorbic acid showed synergism, promoting a greater bleaching effect than when used alone. CONCLUSION: These results suggest the potential use of active soybean flour as a synergistic ingredient in the substitution of artificial additives in bread making. Since the interaction on the bleaching response was not linear and active soybean flour showed a higher iron concentration (66.40 +/- 4.23 mu g g(-1)) than non-active soybean flour (52.30 +/- 0.40 mu g g(-1)), more studies are warranted to establish the biochemical mechanisms involved in this interaction. (c) 2007 Society of Chemical Industry.

Stability and in vitro penetration study of rutin incorporated in a cosmetic emulsion through an alternative model biomembrane

Rutin is employed as antioxidant and to prevent the capillary fragility and, when incorporated in cosmetic emulsions, it must target the action site. In vitro cutaneous penetration studies through human skin is the ideal situation, however, there are difficulties to obtain and to maintain this tissue viability. Among the membrane models, shed snake skin presents itself as pure stratum corneum, providing barrier function similar to human and it is obtained without the animal sacrifice. The objectives of this research were the development and stability evaluation of a cosmetic emulsion containing rutin and propylene glycol (penetration enhancer) and the evaluation or rutin in vitro cutaneous penetration and retention from the emulsion, employing an alternative model biomembrane. Emulsion was developed with rutin and propylene glycol, both at 5.0% w/w. Active substance presented on the formulation was quantified by a validated spectrophotometric method at 361.0 nm. Rutin Rutin cutaneous penetration and retention was performed in vertical diffusion cells with shed snake skin of Crotalus durissus, as alternative model biomembrane, and distilled water and ethanol 99.5% (1:1), as receptor fluid. The experiment was conducted for six hours, at 37.0 +/- 0.5 degrees C with constant stirring of 300 rpm. Spectrophotometry at 410.0 nm, previously validated, determined the active substance after cutaneous penetration/ retention. Emulsion did not promote rutin cutaneous penetration through C. durissus skin, retaining 0.931 +/- 0.0391 mu g rutin/mg shed snake skin. The referred formulation was chemically stable for 30 days after stored at 25.0 +/- 2.0 degrees C, 5.0 +/- 0.5 degrees C and 45.0 +/- 0.5 degrees C. In conclusion, it has not been verified the active cutaneous penetration through the model biomembrane, but only its retention on the Crotalus durissus stratum corneum, condition considered stable for 30 days.

In vitro safety assessment of papain on human skin: A qualitative Light and Transmission Electron Microscopy (TEM) study

Papain is a thiol proteolytic enzyme widely used in dermatology that found applications in wound treatment. Recently, papain was also used as absorption enhancer which can modify the peptide/ protein material in the bilayer domain. We investigated papain safety using human skin that was exposed to papain in vitro at different times: 4, 24 and 48 hours. The samples were examined using Light and Transmission Electron Microscopy (TEM) to study of the mechanisms involved in enhancer-skin interaction. After 24 hours, changes occurred in corneosomes. However, samples of 48 hours did not show major changes in agreement with the control. These findings indicated that papain could be used safely onto the skin.