Estudos Tecnológicos em Engenharia

Lycopene: effect of the heat treatment in the chemical structure and bioavailability

Sun, 30 Dec 2018 00:00:00 -0200

Lycopene is a bioactive compound that belongs to the group of carotenoids, and is responsible for red color of many fruits. Its chemical structure is composed of isoprene units, containing 11 conjugated double bonds, which characterizes it as an antioxidant. The antioxidant capacity of lycopene is mainly due to its free radical scavenging activity, since the molecules are capable of receiving electrons of reactive species. This review aims to describe the antioxidant activity of lycopene, and the changes that occur during thermal processing of lycopene-rich foods, as well as the lycopene bioavailability. Several factors can affect the bioavailability of lycopene, and the main factor is related to its isomeric form. Although foods in natura contains lycopene mainly in the form of trans-isomer, the cis-isomers of lycopene are better absorbed by the human body, which are found mainly in heat-treated foods. This type of processing increases the bioavailability of lycopene, due to the disruption of cell walls, releasing cis isomers of lycopene; however, little is known about the amount of energy required for isomerization without compromising the total lycopene levels, since it can be degraded during thermal processing. Further studies are needed about the effect of processing on the content and the isomeric form proportion of this carotenoid, as well the antioxidant activity of the different isomers.

Keywords:Lycopene, Antioxidant, Isomerization, Bioavailability, Health, Processing

Analysis of vibration levels in users of urban trains

Mário Fedatto Neto, Herbert Martins Gomes — Sun, 30 Dec 2018 00:00:00 -0200

Urban trains and subways are a Brazilian reality. One major aspect that is delegated to a second plan, concerns the quality transportation referred to availability, capacity and safety. Lately, vibration and noise produced by this means of transport have been affecting the life quality in neighborhoods as well as their users. In this paper, the whole body vibration levels in urban trains in Porto Alegre (Trensurb) are evaluated in some situations. Regarding the vibration and rms acceleration doses, the measured values were very low for the back, seat and floor in the vehicle which resulted below the action limit 0.5 m/s² thus, far from the exposure limit 1.1 m/s2 for an 8h exposure time. Generally speaking, the measured vibration levels are considered comfortable, according to values defined in standards, however in some positions and situation, they can be considered uncomfortable.

Keywords: Whole Body Vibration (WBV), Trains, Subways, ISO 2631.

Characterization of residues generated in the harvest and processing of pomiculture for energy purposes in polydispersed fluidized beds

Sun, 30 Dec 2018 00:00:00 -0200

Brazil is prominent in world fruit production, behind only China and India. Orange, banana and apple are the most cultivated fruits nationally. According to the Food and Agriculture Organization (2012), apple is the second most consumed fruit in natura in the world. Apple production generates a large amount of waste, from the orchard to storage, and in the processing industry. Pruning is the stage of production in which more waste is generated, and an average of 5 tons / ha of wood residue can be estimated. In the classification and storage stage, fruits that do not fall into the commercial categories are destined to the processing industry, where, after the processing, the residue is the bagasse. Considering the great energetic potential of these residues, it is interesting to study their use in biorefinery processes. The objective of this study is to investigate the potential use of the residues of the pomicultura (branches, leaves and apple of discard) in processes of biorrefinaria for energetic purposes. For this, the residue samples were characterized for their thermochemical and thermogravimetric properties, and were tested in laboratory scale fluidization equipment. The upper calorific value for apple tree branch, apple leaf and discard was 18,427 MJ / kg, 19,900 MJ / kg and 16,501 MJ / kg, respectively. In the thermogravimetric curves, the zones were observed the mass losses related to the moisture content of the sample, at 100 ° C, related to degradation of cellulose, hemicelluloses and lignin, at 230 ° C, 260 ° C and 350 ° C respectively. The samples tested in the bed corresponded to mixtures between biomass and sand, used as an inert material. The biomass mass percentages present in the tested mixtures were 10%, 30%, 50%, 70% and 90%. For mixtures containing 10%, 30% and 50% of the biomass volume, the fluidization characteristic curves were observed. In fluidization for mixtures with 50% of its volume composed of biomass, despite the formation of preferred paths, it was possible to verify the fluidization phenomenon. What was not possible to verify In the mixtures containing a volume of 70-90% of biomass. However, in these mixtures, two cases were observed: formation of large preferential paths and segregation of particles. Comparing the physical characteristics with eucalyptus and pinus biomasses, which fluidize with mixtures of 70% of the biomass volume, the non-fluidization of the mixture containing a volume greater than 50% of apple tree branches may possibly be explained by the difference in the shape of the particles . However, it was possible to conclude that the use of waste from apple production has a high potential for energy use in biorefinery processes due to its thermochemical characteristics. However, it is necessary to carry out more precise analyzes to base the results obtained in relation to chemical and energy fractions in order to obtain greater efficiency and yield.

Keywords: Integral use. Potential energy. Chemical characterization. Biorefinery.

Laminated polyester composite plates, jute fabric and wood residues

Sun, 30 Dec 2018 00:00:00 -0200

In this work were developed and characterized composite materials of unsaturated polyester matrix, in the presence of wood residue (maracatiara, marupá and angelim stone) and natural fiber (jute) in the form of flat tissue. The manufacturing processes used in this work were manual lamination and cold compression. Specimen of composite materials with polyester/wood residues and hybrid composites of polyester/jute fabric/wood residues were manufactured. The mechanical behaviour of traction composites was evaluated according to ASTM procedures and micrographs at MEV of the fracture surface. The manufacturing methodology used proved to be satisfactory mainly due to the properties of the matrix and for the load in the form of splinters (shavings).

Keywords: Composite materials; Polyester matrix; Jute fabric; Wood residue.

Extraction and application of orange peel essential oil as a natural ingredient

Andressa Neuhaus Ferronatto, Rochele Cassanta Rossi — Sun, 30 Dec 2018 00:00:00 -0200

The extraction of essential oils, products from plants secondary metabolites, has beneficial features for acting as antioxidants, anticancer, antimicrobial, antifungal and among others. This research evaluated the chemical profile and the antioxidant capacity of the essential oil obtained from Citrus sinensis (L.) Osbeck peel and its potential as natural ingredient in product development. The essential oil was extracted by hydrodistillation method with Clevenger. The antioxidant activity was assessed by capturing free radicals through ABTS•+ and DPPH methods and the phytochemical profile was assessed by gas chromatography coupled to mass spectrometry (GC/MS). D-Limonene (94.1%) and Beta-Myrcene (2.46%) were found as major compounds. The IC50 to DPPH test occurred at 0.02 ?molET/mL and IP test at 0.03 ?molET/mL concentrations. reaching inhibition of 81.45%. At ABTS test, IC50 occurred around 11?molET/L and IP at 20 ?molET/L, reaching inhibition of 94.64%. After chemical analysis, it was developed an orange flavor gelatin containing the essential oil extracted. The product quality had been tested by sensorial analysis on 7 points hedonistic scale with 60 students from UNISINOS University. The grades obtained to flavor, aroma and texture were around 6 and 7 (really enjoyed it). To appearance attribute, the grades were lower and the average grade was 5 (moderately liked). The global acceptation rate was 83.21%. Thus, it was concluded that the natural gelatin containing essential oil was well accepted by the evaluators. It means it may be marketed for its antioxidant properties as well as for its sensory properties, being aligned to consumer behavior and new market trends.

Keywords: Essential oils. Citrus sinensis (L.) Osbeck. Gas chromatography. Antioxidant capacity. Sensory analysis.