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The spectroscopy is a technique that provides information about the
molecular structure of a substance. This technique is presently widely used
in pharmaceuticals, food, medical, textile applications, among others due to
the use of samples without manipulation.
Spectroscopy studies interaction between electromagnetic radiation with matter,
by determining the energy levels of atoms and molecules. The total energy of
a molecule is the sum of the electronic, vibrational and rotational energy.
The infrared spectroscopy and Raman spectroscopy are two techniques
used for faster identification, they are easy to use, requiring a little amount
of samples as well as providing information about the sample composition.
Two case studies related to application of these methodologies in food
industry were also presented.
A qualidade da cortiça natural (cortiça de reprodução em bruto, preparada ou trabalhada por simples talha) baseia-se, fundamentalmente, no rendimento de rolhas de boa qualidade.
Uma rolha de boa qualidade é aquela que apresenta um mínimo de porosidade, cor clara e uniformidade, ausência de incrustações estranhas e elasticidade regular para que seja perfeitamente estanque.
Para além da porosidade e da elasticidade, a resistência de uma rolha à torção é uma característica importante para o seu uso, uma vez que, o rolhamento e desenrolhamento de uma garrafa exige por parte da rolha um elevado esforço de torção. Neste contexto e no seguimento de um trabalho anteriormente realizado sobre a determinação da porosidade, pareceu justificar-se uma breve análise a esta característica, bem como a sua possível correlação com estes parâmetros.
Comunicação apresentada no 4.º Congresso Florestal Nacional que decorreu em Évora em 2001.
http://dx.doi.org/10.1016/j.gca.2009.05.001
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This study attempted to apply a rapid method for the determination of methanol,
acetaldehyde and ethyl acetate in wine spirits, brandies and grape marc spirits, using
Fourier Transform Infrared – Attenuated Total Reflectance (ATR) Spectroscopy.
Comunicação oral da qual só está disponível o resumo.
Evaluation of alcoholic beverages with wild berries: alcoholic beverages with juniper berry and blueberry liquor.
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Comunicação da qual só está disponível o resumo.
info:eu-repo/semantics/publishedVersion
Comunicação apresentada no 4.º Congresso Florestal Nacional que decorreu em Évora em 2001.
Com o presente trabalho pretende-se aprofundar o conhecimento sobre o potencial papeleiro da madeira de Acacia melanoxylon e Acacia dealbata. Para efeitos de posicionamento relativo das matérias primas, utilizaram-se aparas industriais de Eucalyptus globulus. A transformação da madeira em pasta foi realizada através do processo ao sulfato. O comportamento global das três espécies nos processos de cozimento e branqueamento é semelhante. No entanto, face à amostra de Eucalyptus globulus usada, a Acacia melanoxylon exibe um rendimento em pasta ligeiramente superior, o que está de acordo com os teores de lenhina e extractivos das madeiras.
Para avaliar o potencial das pastas branqueadas na produção de papel, estas foram submetidas ao processo de refinação, em PFI, tendo-se obtido suspensões de pastas com resistência à drenagem crescentes. Posteriormente, caracterizou-se a suspensão fibrosa e o potencial papeleiro. Para o mesmo nível de refinação, os papéis produzidos com fibras de acácia apresentam valores superiores de lisura, índice de tracção e índice de rebentamento. Por outro lado, as fibras da Eucalyptus globulus apresentam maior resistência intrínseca e têm potencial para produzir papeis mais resistentes, embora à custa de maior consumo de energia na refinação. Para um dado nível de resistência mecânica, as características ópticas dos papéis são semelhantes.
http://dx.doi.org/10.1016/j.gca.2010.04.026
DOI 10.1007/s00107-008-0248-2
Este estudo analisa o efeito do teor de hemiceluloses das pastas de eucalipto nas características do papel produzido. Para o efeito, utilizaram-se aparas industriais de Eucalyptus globulus, com massa volúmica básica de 536 ± 4 kg/m3. As aparas crivadas foram sujeitas ao processo kraft, convencional e modificado, para a produção das respectivas pastas cruas com teores de hemiceluloses diferentes. Os cozimentos realizaram-se num digestor descontínuo de circulação forçada, com 1000g de madeira. A pasta crua foi submetida a um branqueamento ECF com dióxido de cloro, segundo uma sequência de cinco estágios (D0E1D1E2D2). As duas pastas, convencional e modificada, apresentaram teores de hemiceluloses da ordem dos 19% e 14%, respectivamente.
Posteriormente, a pasta branca foi caracterizada em termos biométricos e papeleiro. Para este fim, a pasta foi refinada em PFI (ISO 5264/2-79) a diversas revoluções e com uma carga específica de bordo de 2 Nmm-1, tendo-se contabilizado o consumo de energia. Caracterizou¬-se a suspensão fibrosa e o potencial papeleiro. Para um dado número de revoluções em PFI, a resistência à drenagem, a densidade e a resistência à tracção das folhas aumentam com o incremento do teor de hemiceluloses. Assim, para produzir papéis com a mesma densidade, as pastas com menor teor de hemiceluloses requerem mais energia de refinação.
DOI 10.1007/s00107-010-0516-9
The alcoholic drink called “aguardente de zimbro” is normally presented at touristic
documentation about “Serra da Estrela” and included in the food heritage of the region.
However, there is a lack of technical and scientific information about this beverage.
This work intends to achieve a first characterization of this product concerning its technology,
and its sensory properties and physico-chemical characteristics. A few number of commercial
samples of this product and other alcoholic beverages made with juniper were analyzed. It
was performed several analytical determinations to the samples, namely alcoholic strength,
dry matter, total acidity, fixed acidity, volatile acidity, pH, chromatic characteristics,
methanol, acetaldehyde and ethyl acetate in order to characterize analytically the juniper
spirits, namely the Portuguese ones. It was also done the descriptive sensory analysis of the
beverages.
Based on the results the three Portuguese commercial beverages “Aguardente de zimbro”,
which are currently in the market, seem to be made from three different alcoholic distillates
(grape marc spirit, wine spirit and arbutus spirit).
The three commercial beverages presented a yellowish colour. However, the three beverages
presented a quite different flavour profile, so further research is needed in order to establish
and understand the sensory profile of the traditional beverage.
This paper reports on the relationship between the fibre morphology of six Acacia melanoxylon bleached kraft pulps, produced from wood chips with basic densities of 449, 489, 493, 505, 514 and 616 kg/m3, and their papermaking potential.
In order to assess the choice made by honey bees all over the time two apiaries in the
region of Beira Interior were selected for evaluation of the variance of floral pollen sources
used by them in three different flowering periods.
The behaviour of cork under tensile stress in the tangential direction was evaluated in relation
with its structural characteristics
Este estudo tem como principais objectivos determinar o perfil do consumidor do mel em Portugal e as suas atitudes face ao produto, à produção e ao consumo de mel.
Para esse efeito foi elaborado e aplicado um questionário directo online. Este questionário foi aplicado uma amostra representativa de 1037 indivíduos. Foi efectuado um pré-teste do inquérito com cerca de 30 inquiridos.
Foram ainda analisadas as atitudes face ao produto, o apoio à apicultura, o foco apícola e as normas subjectivas sobre a produção e ao consumo de mel efectuado de acordo com da Teoria do Comportamento Planeado (TCP) de Ajzen.
Este estudo tem como principais objectivos determinar o perfil do consumidor do mel
em Portugal e as suas atitudes face ao produto, à produção e ao consumo de mel.Para esse efeito foi elaborado e aplicado um questionário a uma amostra
representativa de 1025 indivíduos. Foi efectuado um pré-teste do inquérito com cerca
de 30 inquiridos, tendo-se de seguida procedido ao envio do inquérito final.
Para análise dos dados recorreu-se à Estatística descritiva das variáveis em estudo e
efectuou-se o cálculo do índice de consistência interna alpha de Cronbach, tendo
registado um valor superior a 0,8.
O agregado familiar dos inquiridos é, na sua maioria, constituído por 3 elementos. Da
totalidade da amostra 12 % são produtores de mel, o que é um bom indicativo, pois
durante algum tempo pensou-se que apenas os produtores consumiam mais mel. Dos
consumidores 40% fazem-no regularmente (todos os dias ou semanalmente).
Cerca de 95% dos portugueses consomem mel português por entenderem que é de
qualidade, e de confiança.
Poucos inquiridos conhecem a diferenciação entre mel monofloral e multifloral, pelo
que não é uma opção quando da sua compra.
O mel é o produto da colmeia mais conhecido e consumido, sendo que alguns
inquiridos desconhecem a existência de outros produtos.
Foram ainda analisadas as atitudes atitudes face ao produto, o apoio à apicultura, o
foco apícola e as normas subjectivas sobre a produção e ao consumo de mel
efectuado de acordo com da Teoria do Comportamento Planeado (TCP) de Ajzen.
Assim, relativamente às actitudes relativas ao produto, verifica-se que os inquiridos
concordam fortemente que o mel é um produto natural com propriedades terapéuticas
devendo fazer parte da alimentação. Sobre os aspectos relacionados com a produção
e o consumo de mel um terço dos inquiridos concorda que os amigos e a família
pensam que os apicultores apenas produzem produtos melíferos. A grande maioria da
amostra concorda ou concorda fortemente que os amigos e a família consideram que
o mel é extremamente benéfico para a saúde.
Comunicação oral da qual só está disponível o resumo.
Cork is known as the material used for the production of wine stoppers. The specific properties of
cork, e.g. low density, very low permeability to water, elastic properties and inertness have made it the
best sealant for quality wine. Here we studied the relation between compression, tensile and bending
stress in cork and the influence of structural characteristics of cork on its mechanical behaviour. The
material was sampled from raw cork planks of good quality (class 1) and poor quality (class 4) collected at
one industrial mill after post-harvest six-month air stabilization, water boiling and air drying as usually
applied in cork industrial processing. The samples had densities ranging 0.123 - 0.203 g.cm-3 and
porosities between 0.5 and 22.0%.
There are differences between the type of stress and the corresponding direction of stress. For
the same direction of stress, the Young modulus in tension is higher then in bending and it is lowest in
compression. The bending Young modulii were well correlated with the tensile Young modulii, because
while in bending the sample is submitted to both tensile and compression stresses, the fracture occurs in
the tensile zone. There were no significant differences in the mechanical properties of cork samples
obtained from cork planks of different quality classes but the density is an important factor and samples
with higher density showed overall larger resistance. Mechanical properties were influenced by the
structural features related to the lenticular channels, namely the presence of thick walled and lignified cells
that may border the lenticular channels.
The manufacturing process of wood agglomerate integrates distinct unit that transforms wood raw material into wood agglomerate. The yield of wood agglomerate produced is influenced by the density and the quality of the initial raw material. This work has compared two distinct methodologies aimed at defining the yield of the process through an indirect measurement at the precursor material.
Samples (logs of differentiated sizes) were collected immediately at the industry entrance and several parameters were measured. The logs basic density and the moisture content was annotated, through analysis of the corresponding dry and wet mass. Log bark percentage has estimated also at the level of dry and wet basis. These parameters were used to determine the wood volume from different provenance and species in the beginning of the industrial process.
The results indicated that wasn’t a great difference between the two different methods to determine the wood basic density and the wood volume in m3.
Principal components analysis was used to investigate the differences between different provenances and different species for the wood basic density, and we conclude there is a great variability in wood basic density for the hardwood species than the observed for the softwood and there isn’t a great variability between different provenances.
We study too the difference off wood moisture that could be occurring before the evaluation of wood basic density.
O planeamento metódico do território permite, extrair o potencial de cada região e preservar os recursos naturais. Os municípios do Crato e de Portalegre, apresentam boas condições edafo-climáticas para a de um mel de prática agrícola, apresentando uma floração sucessiva e diversificada, o que conduz à produção de excelente qualidade. A área de estudo encontra-se na Zona Controlada sob gestão da Apilegre. Este estudo enquadra-se no seguimento de outros trabalhos anteriormente desenvolvidos pela mesma equipa e pretende integrar vários parâmetros biofísicos, através de uma metodologia de análise espacial, para apoio à tomada de decisão na instalação de apiários. As cartas de zonas com potencial apícola e as zonas interditas são elementos importantes no apoio ao ordenamento apícola e que podem ser melhorados com a integração de novas variáveis, tais como: a influência do uso de pesticidas na agricultura e a proximidade a fontes de radiação eletromagnética.
Este estudo analisa o efeito do teor de hemiceluloses das pastas de eucalipto nas características do papel produzido. Para o efeito, utilizaram-se aparas industriais de Eucalyptus globulus, com massa volúmica básica de 536 ± 4 kg/m3. As aparas crivadas foram sujeitas ao processo kraft, convencional e modificado, para a produção das respectivas pastas cruas com teores de hemiceluloses diferentes. Os cozimentos realizaram-se num digestor descontínuo de circulação forçada, com 1000g de madeira. A pasta crua foi submetida a um branqueamento ECF com dióxido de cloro, segundo uma sequência de cinco estágios (D0E1D1E2D2). As duas pastas, convencional e modificada, apresentaram teores de hemiceluloses da ordem dos 19% e 14%, respectivamente.
Posteriormente, a pasta branca foi caracterizada em termos biométricos e papeleiro. Para este fim, a pasta foi refinada em PFI (ISO 5264/2-79) a diversas revoluções e com uma carga específica de bordo de 2 Nmm-1, tendo-se contabilizado o consumo de energia. Caracterizou-se a suspensão fibrosa e o potencial papeleiro. Para um dado número de revoluções em PFI, a resistência à drenagem, a densidade e a resistência à tracção das folhas aumentam com o incremento do teor de hemiceluloses. Assim, para produzir papéis com a mesma densidade, as pastas com menor teor de hemiceluloses requerem mais energia de refinação.
We measured fibre morphological properties and corresponding handsheet paper properties in pulps obtained from Eucalyptus globulus, Acacia dealbata and Acacia melanoxylon wood samples. The three wood samples were chipped, cooked, and bleached according to standard procedures. The basic chip densities of the samples obtained from the three species studied were 0.351g/cm3, 0.387g/cm3 and 0.536g/cm3, respectively for A. dealbata, A. melanoxylon and E. globulus. All species were submitted to cooking with the following reaction conditions: active alkali charge = 22% (as NaOH); sulfidity index = 30%; liquor/wood ratio = 4/1; time to temperature = 90 min; time at temperature (160 ºC) = 120 min.
Acacia species show higher pulp yield than the E. globulus sample used as a reference and cooking selectivity is higher in the Acacia species investigated.
The three pulps were beaten in a PFI mill at 500, 2500 and 4500 revolutions under a refining intensity of 3.33 N/mm, and laboratory paper sheets were produced, including the unbeaten pulps, which made up 4 samples per species. The corresponding fibre characteristics in suspension were also determined.
We used principal components analysis to investigate the differences in fibre characteristics and paper properties, as well as their interaction. Each value of these variables represents a mean of 10 tests, for the paper sheets. This methodology allowed us to determine how close, or how independent, the study variables were.
We conclude there is a group of paper characteristics which depend strongly on each other - paper density, smoothness, tensile index, stretch, burst index, Schopper Riegler degree, internal cohesion and WRV – and are negatively correlated with the light scattering coefficient, opacity and brightness.
On the other hand, intrinsic paper fibre resistance is strongly affected by fibre length and coarseness.
On the basis of the properties we studied, it is clear that paper produced from Eucalyptus fibre has different properties from that produced from Acacia fibre. Papers produced from both species of Acacia are similar.
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In this paper we studied the retraction of veneer sheets of a diffuse-porous specie (beech) and a ring-porous specie (oak) during the drying process. For each specie we analysed radial and tangential sections, since the differences obtained relate to vessel distribution across the axial or non axial section. Thus, we studied the following parameters: thickness, moisture content, retraction of axial and non axial (radial or tangential) direction.
We used 10 beech logs, from which we took 30 samples with a radial cut and 30 samples with a tangential cut. From each log we took 6 veneer sheets. We applied the same procedure to the oak logs. All our veneer sheets were 0,6mm thick. Immediately after cutting, we measured the thickness, moisture content, length and width of each veneer sheet. We measured the same parameters again after the drying process.
The two species behaved differently, which we attribute to their distinct anatomical structure, even though both are hardwoods. Variance analyses showed that the species is the main responsible for the variation, and that beech has a higher shrinkage variation. Higher shrinkage results from the tangential cuts, compared to radial cuts.
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The alcoholic drink called ‘aguardente de zimbro’ is a traditional Portuguese alcoholic beverage made by the people living around Serra da Estrela, using the maceration of juniper berries in different distillates like arbutus spirit, marc spirit and wine spirit. Traditionally homemade for own consumption in rural families, this beverage is now sold to tourists and promoted and included in the food patrimony of the region. However, there is a lack of technical and scientific information about this beverage. A first evaluation of this beverage is done in this work, based on its sensory and physicochemical characteristics. A few commercial samples, two homemade and another two samples of alcoholic beverages made with juniper were analysed in this work. Several analytical determinations, namely density, alcoholic strength, dry matter, total acidity, fixed acidity, volatile acidity, pH, chromatic characteristics, methanol, acetaldehyde, ethyl acetate, fusel alcohols and total antioxidant activity were done on the samples with the aim of characterising these Portuguese flavoured juniper spirits. The descriptive sensory analysis of these drinks was also done in order to find the more characteristic sensory attributes of the drink. The results show that under the label ‘aguardente de zimbro’ there are several drinks, with a yellow colour, but with several differences in physicochemical composition and sensory description. In fact, these drinks, with ethanol content from 37.7 to 48.3 % vol. present values of acidity from 25 to 1360 mg/L, pH from 3.91 to 5.89, dry matter 0.75 to 75.24 g/L and density from 0.9446 to 0.9770 g/cm3. Important differences were also observed in the chromatic characteristics, volatile composition and total antioxidant activity. Therefore, further research must be done in order to characterise this ‘traditional’ drink.
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Com este texto pretende-se efetuar uma revisão sobre a produção e utilização de pinho. São referidos os dois tipos de óleo de pinho - sintético e natural- realçando-se as reações químicas e a sua produção, assim como, a composição e as propriedades do produto. Faz-se ainda uma referência às principais utilizações deste produto - limpeza e desinfetante, aplicação na indústria têxtil e na flotação de minérios. Por último faz-se referência ao óleo de pinho obtido das folhas das coníferas.
Relation between wood density and paper properties of some hardwood species.
In this work we studied the effect of moisture and chip pile storage time of Eucalyptus globulus wood, regarding the impact in kraft cooking and papermaking.
Experimentally, chip samples were collected with different storage times (0, 15, 30, 60 and 90 days) from two distinct piles (wet and dry). The cooked chips after disintegration, screening and washing were submitted to a bleaching stage, in ECF sequence following five stages (D0E1D1E2D2). The pulps were beaten in a PFI mill at 1000, 2000 and 3000 revolutions. For the cooking results we observed higher yield and lower alkali consumption for the wet pile chips and lower storage time (15 days).
The results showed that storage time is a significant factor (ANOVA results) for almost paper properties studied and influenced mainly the internal fibre links. For what paper properties are concerned, the difference between piles isn’t so evident, the major differences are observed for the lower storage time (15 days).
Wood density is a complex physical property related to the anatomical structure and the chemical composition of
wood and one of the most important wood quality factors. Sampling was based on a total of 20 trees from four
sites in Portugal that were harvested at a sawmill diameter class of 40 cm and wood discs taken at different
height levels from the base to the top of the tree.
The mean basic density of the Acacia melanoxylon trees measured at 5% height level (near breast height level)
was 516 kg/m3 with a 34 kg/m3 standard deviation. The within-tree axial variation of density was of small
magnitude, but showing higher values at the stem base and top. Site had no influence on the basic density of the
wood. Overall the between tree variation of density was small possibly linked to the narrow genetic diversity of
this introduced exotic species. In the Kraft process we can observe variability between stands and an increase of
the pulp yield, and fiber width and length with the higher level in the tree. The wood basic density is well
correlated with the ISO brightness and well correlated in inverse order with the pulp Yield and fiber width and
length. The kappa number don’t present a great variation with the wood basic density.
This paper reports experimental data about
wood chemical composition (extractives and
lignin content), fibre characteristics, kraft cooking
behaviour and papermaking potential of two
wood samples of Eucalyptus globulus (one
industrial chip sample and another obtained
from a clone tree). The samples were submitted
to the kraft cooking and bleaching processes in
order to evaluate its pulping potential. The
experimental results showed that the clone tree
requires milder cooking conditions and exhibits
higher pulp yield. The pulp fibres obtained from
the clone have higher fibre length and fibre width
and lower coarseness, which give higher fibre
flexibility and collapsibility. In consequence,
structural, mechanical and optical properties of
paper are significantly different. In addition, we
observed that the fibres from the clone tree are
weaker than the corresponding fibres from the
industrial sample.
The raw-material composition and the cooking conditions determine the pulp composition and this affect the behaviour of the pulp in the beating process and the papermaking potential. However, at industrial scale the variability of the pulp composition, for a given raw material and a given process, is relatively low and usually it is difficult to quantify the impacts of pulp composition on beating and papermaking.
In the present study E. globulus bleached pulps were produced under different cooking conditions by the kraft process in order to obtain pulps with significant different hemicelluloses content (19% versus 14.5%). The behaviour of the pulps in beating and the papermaking potential were investigated under two beating intensities in the PFI mill and at four beating times. The pulp suspensions were characterised in terms of drainability, fibre morphology, wet fibre flexibility and relative bonded area. The paper produced was evaluated in terms of structural, superficial, mechanical and optical properties. The results showed the clear effect of the hemicelluloses content on the beating rate as well as on the paper properties.
In this paper, the morphological properties of fiber length (weighted in length) and
of fiber width of unbleached Kraft pulp of Acacia melanoxylon were determined using TECHPAP
Morfir equipment (Techpap SAS, Grenoble, France), and were used in the calibration development
of Near Infrared (NIR) partial least squares regression (PLS-R) models based on the spectral data
obtained for the wood. It is the first time that fiber length and width of pulp were predicted with
NIR spectral data of the initial woodmeal, with high accuracy and precision, and with ratios of
performance to deviation (RPD) fulfilling the requirements for screening in breeding programs.
The selected models for fiber length and fiber width used the second derivative and first derivative
+ multiplicative scatter correction (2ndDer and 1stDer + MSC) pre-processed spectra, respectively,
in the wavenumber ranges from 7506 to 5440 cm 1. The statistical parameters of cross-validation
(RMSECV (root mean square error of cross-validation) of 0.009 mm and 0.39 m) and validation
(RMSEP (root mean square error of prediction) of 0.007 mm and 0.36 m) with RPDTS (ratios of
performance to deviation of test set) values of 3.9 and 3.3, respectively, confirmed that the models
are robust and well qualified for prediction. This modeling approach shows a high potential to be
used for tree breeding and improvement programs, providing a rapid screening for desired fiber
morphological properties of pulp prediction.
The Multicriteria decision analysis is a tool to support decision-making in the identification of areas with the utmost beekeeping potential.
This paper design a GIS multicriteria approach to assess the beekeeping potential. The development of a conceptual model structure
requires the participation of stakeholders and experts in that process. The spatial Multicriteria Decision Analysis (MCDA) allowed defining
the potential beekeeping map. The resulting maps can be used by the beekeepers associations to easily select the more suitable areas for the
apiaries location or relocation and avoid prohibited areas by legal requirements.
In this paper, the morphological properties of fiber length (weighted in length) and of fiber width of unbleached Kraft pulp of Acacia melanoxylon were determined using TECHPAP Morfi® equipment (Techpap SAS, Grenoble, France), and were used in the calibration development of Near Infrared (NIR) partial least squares regression (PLS-R) models based on the spectral data obtained for the wood. It is the first time that fiber length and width of pulp were predicted with NIR spectral data of the initial woodmeal, with high accuracy and precision, and with ratios of performance to deviation (RPD) fulfilling the requirements for screening in breeding programs. The selected models for fiber length and fiber width used the second derivative and first derivative + multiplicative scatter correction (2ndDer and 1stDer + MSC) pre-processed spectra, respectively, in the wavenumber ranges from 7506 to 5440 cm−1. The statistical parameters of cross-validation (RMSECV (root mean square error of cross-validation) of 0.009 mm and 0.39 μm) and validation (RMSEP (root mean square error of prediction) of 0.007 mm and 0.36 μm) with RPDTS (ratios of performance to deviation of test set) values of 3.9 and 3.3, respectively, confirmed that the models are robust and well qualified for prediction. This modeling approach shows a high potential to be used for tree breeding and improvement programs, providing a rapid screening for desired fiber morphological properties of pulp prediction.
Aim of the study: The ability of NIR spectroscopy for predicting the ISO brightness was studied on unbleached Kraft pulps of Acacia melanoxylon R. Br.
Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal.
Materials and methods: The samples were Kraft pulped in standard identical conditions targeted to a kappa number of 15. A Near Infrared (NIR) partial least squares regression (PLSR) model was developed for the ISO brightness prediction using 75 pulp samples with a variation range of 18.9 to 47.9 %.
Main results: Very good correlations between NIR spectra and ISO brightness were obtained. Ten methods were used for PLS analysis (cross validation with 48 samples), and a test set validation was made with 27 samples. The 1stDer pre-processed spectra coupling two wavenumber ranges from 9404 to 7498 cm-1 and 4605 to 4243 cm-1 allowed the best model with a root mean square error of ISO brightness prediction of 0.5 % (RMSEP), a r2 of 99.5 % with a RPD of 14.7.
Research highlights: According to AACC Method 39-00, the present model is sufficiently accurate to be used for process control (RPD ≥ 8).
Pulp yield is an important measure of pulpwood quality, which is used regularly by the pulp and paper industry for which the possibility of using rapid methods to predict pulp yield would be very useful for screening and quality control. This work addresses the prediction of Kraft pulp yield under standard identical conditions and targeted to a kappa number of 15, using near-infrared (NIR) partial least squares regression modelling. A total of 75 pulp samples of Acacia melanoxylon R. Br. (blackwood) with a pulp yield variation range of 47.0–58.2 % were used. Very good correlations between NIR spectra and pulp yield were obtained. Ten methods were used for PLS analysis (cross-validation with 62 samples), and an external validation was made with 13 samples. The 2ndDer pre-processed spectra coupling two wavenumber ranges from 9087 to 5440 and 4605 to 4243 cm−1 allowed the best model with a standard error of prediction of 0.4 %, a r2 of 98.1 %, and the ratios of performance to deviation (RPDTS) of 4.8. According to AACC Method 39-00, the present model is sufficiently accurate to be used in screening programs and in quality control (RPDCV = 6.9).
Modelação espacial do potencial de produção apícola utilizando software open source.
No presente estudo pretendeu-se compreender o efeito da variação do número de pontos da suavização espectral (ou filtro digital) no desenvolvimento de modelos de calibração por FTIR-ATR utilizando técnicas PLS-R para determinações rápidas do teor em metanol e do teor alcoólico em aguardentes.
De acordo com o descrito em ANJOS et al. (2016) as zonas espectrais identificadas foram 1607-977 cm-1 e 3057-2864 + 1292-663 cm-1 respetivamente para o teor em metanol e teor alcoólico, com coeficientes de determinação superiores a 96,3 %. O valor de RPD apresenta qualidade suficiente para utilização em laboratório de controlo de qualidade.
Foi avaliada a robustez dos modelos para 5, 9, 13, 17, 21 e 25 pontos de suavização para o pré-processamento usando a Primeira Derivada (1stDer), aplicando o algoritmo de Savitzky-Golay.
O pólen recolhido pelas abelhas
é geralmente usado com o objetivo
de alimentar as suas larvas nos estágios
iniciais de desenvolvimento, sendo uma
fonte importante de nutrientes
e micronutrientes para as abelhas
jovens da colmeia. Uma alimentação
rica em pólen em fases precoces do
ciclo de vida permite o desenvolvimento
em obreiras fortes e consequentemente
uma colmeia muito ativa e com elevado
rendimento de aprodução de mel
e outros produtos. Devido
à sua constituição química, o pólen
é também um alimento nutricionalmente
importante para os seres humanos.
Utilização de SIG “open source” no ordenamento apícola. Caso de estudo: área controlada de Castelo Branco.
There are several studies reporting the evidence that pollinators are declining as a result of local and global environmental degradation. Operation Pollinator is an international biodiversity program, supported by Syngenta, to boost the number of pollinating insects on commercial farms. It works by creating specific habitats, tailored to local conditions and native insects.
The aim of this work is to increase the ecological suitability of pollinator populations through improves food availability for pollinator employing strategies for surrounding
landscape.
Two cherry orchards, located in Fundão, Portugal, were studied: one was installed a patch meadow with flowery prairie with the purpose of increasing pollinator’s number;
other with poor native biodiversity. It was identified the main groups of insects visiting the cherry blossoms and the surrounding flora, during the flowering cherry trees.
This review was conducted through observation and analysis of pollen in pollinator’s nests, artificially placed in the orchards in order to evaluate the visiting flowers.
There was a greater number of pollinating insects in the orchard with higher biodiversity and it was found that insects visited other flora along with the cherry blossoms. The
Hymenoptera identified belong to genus: Andrena; Apis; Eucera; Tropinota; Anthophora; Osmia; Xylocopa. The orchard where haven’t been installed the patch meadow, shows a lower number of visiting insects as well as lower species variability. The increasing of pollinators protects the environment and increases the fruit production and quality.
The findings of the sweeter fruit, with the increased number and diversity of insects leads to the conclusion that the environment benefits from the increase in pollinators with more balanced environment, it's a winning environment for everyone.
The conservation of pollinator habitat can also enrich overall biodiversity and the ecosystem services, protect soil and water quality
The pulping and papermaking potential of Acacia dealbata and Acacia melanoxylon were studied using Eucalyptus globulus as a reference. Pulp yield, alkali consumption and delignification in the kraft process, of both species, compare very well with the reference. Pulp yield can be higher than that of E. globulus and the residual lignin content lower after cooking, which is in good agreement with the lower lignin and extractives content of the wood samples used. Pulps produced from Acacia have slightly lower fibre length and coarseness and higher fibre width and wet fibre flexibility than E. globulus pulps. As a consequence of fibre characteristics, the paper produced from Acacia is denser and exhibits higher tensile and burst strength, and lower tear resistance than that from E. globulus, at a given PFI revolution.
Introduction: A. melanoxylon wood has a large commercial application given its anatomical characteristics and mechanical properties. However studies on the anatomical characterisation of this species grown in Portugal are scarce.
Objectives: To describe the transverse anatomical characteristics and their within-tree variation of A. melanoxylon trees growing in Portugal.
Methods: 20 trees were analysed in transverse section for tree radial position (10%; 50%; 90%) and five height levels (base, 15%; 35%; 65%; 80%) in north and south directions. Measurements included: fibre diameter (m), fibre wall thickness (m), Runkle index; Flexibility index, vessel number (vessel number /mm2), porosity (%) and vessel width (m).
Results: Earlywood fibres have lower wall thickness and higher lumen diameter than latewood fibres. Runkle and flexibility indexes confirm its potential for pulp and paper production. Porosity was lower near the pith as a result of a slight increase of vessel number with smaller size.
Conclusions: Blackwood showed potential as an alternative species to supply the industry.
Bee pollen, usually used as an important source of nutrients and micronutrients for the young bees in the
hive, is also an important food for humans. This product is very rich in proteins, lipids, free sugars,
carbohydrates, and it contains trace amounts of minerals, phenolic acids, flavonoids and a good range of
vitamins. A brief look at bee pollen composition, it is easily recognised that it is a balanced food that can
be used as a stand-alone food or as a nutritional supplement or even as a medicinal product. Several
bioactivities, due to some of these compounds, were studied in bee pollen samples from different floral
sources and the results conduce to important properties. The amount and diversity of micronutrients could
induce vast benefits if used for health purposes following a complete risk assessment. Nevertheless, the
results pointing towards the encouraged use of bee pollen, the risk assessment of some floral species
containing toxic compounds has not been fully studied to insure the safety of consumption for all the
gathered flowers, so this will also be discussed in this chapter. Admiration for its goodness and medicinal
properties, bee pollen has been consumed for centuries, however, currently the efficacy and safety for all
consumed products, foods, supplements or medicines is an important tool to guarantee correct quality
control and essential to add value to the product.
To summarise, in this chapter we will put the situation of gaps in bee pollen research into some kind of
perspective, outlining some important points and discussing in more depth the implications of collecting
samples, chemical composition and risk assessment.
Application of GC-MS to characterize the volatile composition of fruit distillates made with honey.
Honey is a sweet natural food product produced by honey-bees, characterized by high amounts of available sugars, manly, fructose and glucose, and is a rich source of amino acids, vitamins, minerals and other biologically active compounds. Compared to commercial sugar, honey has a lower glycaemic index (blood sugar levels are raised more quickly) due to its higher fructose content, and absence of trace minerals. Sugar profile (fructose, glucose, sucrose, maltose, turanose and trehalose) of 46 honey samples from Castelo Branco region were analysed by high performance anion-exchange chromatography pulsed amperometric detection (HPAEC-PAD) (Anjos et al., 2015). Fructose/glucose ratio ranges between 1.22 and 1.62 g/100 g of honey. Turanose and maltose were present in all samples, 1.91 to 3.78 g/100 g of honey and 0.48 to 2.14 g/100 g of honey, respectively. In 24% of honey samples, sucrose was present at levels lower than 2.9 g/100 g of honey (actual honey reference). Trehalose was identified only in the honey samples from Sabugal and Sertã Municipality. Sertã honey has higher amount of turanose. Glucose has the lower amount observed for Sabugal and Proença-a-Nova Municipality. Honey carbohydrate composition depends on the flower nectar collected by bees as well the regional climatic conditions. Our results suggest the carbohydrate profile could be a good indicator of honeys’ origin.
This paper reports on the relationship between the fibre morphology of six Acacia melanoxylon bleached kraft pulps, produced from wood chips with basic densities of 449, 489, 493, 505, 514 and 616 kg/m3, and their papermaking potential. Six wood samples were selected in order to provide pulps with markedly different fibre morphological properties. The pulps were beaten in a PFI mill at 500, 2500 and 4500 revolutions under a refining intensity of 1.7 N/mm and their papermaking potential evaluated. The mean values of fibre length, fibre width and coarseness ranged between 0.78 and 0.99 mm, 17.8 and 19.4 cm, and 4.8 and 6.2 mg/100 m, respectively. As expected, the fibres characteristics have very high impact on handsheet structure, including smoothness, and on mechanical and optical properties, for the unbeaten pulps. At a given beating input (same PFI revolutions), the differences between pulps remain very high. Moreover, for a given paper density, tensile and tear strength, and light scattering coefficient are very sensitive to mean pulp fibre characteristics.
Pollen collected by honey bees (bee pollen) is promoted as a health food supplement with a wide range of nutritional and health beneficial properties. While honey is an important source of proteins for the bee colony, pollen is the bees' main source for other important nutrients, such as minerals, fats, fibers, carbohydrates, and other substances. The composition of pollen is rather variable and depends on the botanical origin of the pollen. In this work we studied the mineral content of bee pollen of three botanical origins (Cistus ladanifer L., Rubus ulmifolius Schott, and Calluna vulgaris (L.) Hull) and two geographic sites in the central Portugal (Caniçal and Vale Grande). Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used for the determination of cadmium, chromium, copper, iron, lead, manganese, and zinc. Prior to ICP-AES measurement, the samples were mineralized by treatment with HNO3 and H2O2 at 100 °C until complete digestion. The analyzed elements presented levels corresponding to the usual reference range [1]. The concentrations of micronutrients (Cu, Fe, Mn and Zn) presented characteristic profiles which differed between the three plant species, but where similar in the two geographic areas. The main minerals observed for R. ulmifolius and C. vulgaris were Fe and Mn, and Zn for C. ladanifer. Heavy metals (Cd, Cr and Pb) were present at low concentrations (Table 1), indicating that there were no sources of contamination. In conclusion, the determination of micronutrients in pollen could be suitable for the identification of botanical species. The investigation of element profile, in combination with modern statistical data evaluation techniques, can be a promising approach to identify the botanical source of pollen.
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The compression properties of cork were studied on samples obtained from cork planks of two commercial quality classes (good and poor quality), with densities ranging from 0.12–0.20g cm-3 and porosities from 0.5 to 22.0%. The stress-strain curves were characterized by an elastic region up to approximately 5% strain, followed by a large plateau up to 60% strain caused by the progressive buckling of cell walls, and a steep stress increase for higher strains corresponding to cell collapse. The direction of compression was a highly significant factor of variation, with cork showing higher strength for the radial compression.
Density influenced compression and cork samples with higher density showed overall larger resistance to compression in the three directions. In the elastic region, an exponential model of Young’s modulus in function of cork density could be adjusted.
The effect of porosity on compression was small and the stress-strain curves were similar regardless of the porosity of the samples, although there was a trend toward an overall increase of stress with porosity for higher strains. Porosity was characterised by a high variability in the anatomical features of the lenticular filling material and the presence of collapsed and thick walled lignified cells. The inclusion of a porosity parameter for the modelling of the elastic modulus did not improve the prediction obtained with density-based models.
There was no significant difference in the compression properties of cork samples obtained from cork planks of good and poor quality classes.
The behaviour of cork under tensile stress in the axial direction was studied for samples taken from cork planks of good (class 1) and poor (class 4) quality grades and at three radial positions within the plank (inner, mid and outer positions). The effect of cork density (ranging from 0.123 to 0.203 g cm−3) and porosity (ranging from 2.8 to 9.6% in the tangential surface) on Young’s modulus and fracture stress and strain was studied. The tensile stress-strain curves of cork showed an elastic deformation up to 2% strain with a Young’s modulus of 30.8 MPa, and a fracture stress of 1.05 MPa at a strain of 7.1% for class 1, and Young’s modulus of 26.1 MPa, and a fracture stress of 0.77 MPa at a strain of 5.5% for class 4. Fracture always started at a pore. The quality class and the radial position in the plank were highly significant factors of the tensile properties variation with good quality cork in the inner part of the plank showing the highest strength. Density influenced the elastic behaviour of cork with a highly significant correlation of increasing E with density, but not so clearly the fracture stress and strain. The variability of tensile properties with porosity was large and although significant, the correlations were lower in spite of a decreasing trend of E with porosity. Fracture depended on the type of defects in cork
Following harvest, bee pollen must be submitted to processing in order to maintain properties for consumers’ health insurance. In this study, the changes on the lipid profile, contents of vitamin C, β‐carotene and lycopene of bee pollen samples submitted to two conservation methods (freezing and drying) are evaluated. Eleven fatty acids, eight saturated, one monounsaturated, and two polyunsaturated are quantified. The PUFA/SFA ratio ranges from 1.18 to 3.95 g 100−1 g−1 and is significantly higher in the frozen extracts. On the other hand, the ratio n6:n3 (ranging between 0.36 and 0.86 g 100−1 g−1) did not differ among processing methodologies, for most of the cases. The atherogenicity (AI) and thrombogenecity (TI) indexes are similar among preservation processes and coherent with the found on other health‐promoting foods. The contents of vitamin C, β‐carotene and lycopene are, for all samples, significantly superior in the frozen bee pollen.
Distilled spirits are usually made from fermented sugar-based materials, such as wines or fermented fruits, but other products can be used, namely berries or honey. In this work, an evaluation of honey spirits is done based on its physicochemical and sensory characteristics. Fourteen honey spirit samples of different brands of honey spirit were purchased at the market and from artisan Portuguese producers. Several analytical determinations, namely alcoholic strength, dry matter, density, total acidity, chromatic characteristics, methanol, acetaldehyde, ethyl acetate and higher alcohols were done to characterize all samples. The results pointed out several differences in physicochemical composition of samples. In general, these drinks are characterized by an alcohol strength between 37.4% and 53.0% and a low methanol content, quite null for most samples. Samples with higher ethanol content corresponded to the artisanal samples. Significant differences (p < 0.05) were also observed in the volatile composition and chromatic characteristics suggesting different production technologies. A first list of sensory attributes was obtained for this beverage. Therefore, further research must be done in order to characterize this spirit drink, which has gained market value.
Aplicação de técnicas de espectroscopia no infravermelho na caracterização de “Azeites de Montanha"
Comunicação apresentada na 8th International IUFRO Wood Drying Conference, que decorreu de 28 a 29 de Agosto em Brasov na Roménia.
Together the forest and industrial activities within the Portuguese forest sector have a
great importance in the national economy. The most used wood species in Portugal for industry
(wood panel, sawmill, wood crates) are pine and eucalypt, which leads to extreme dependence
and competition between the various industries for the same material, and thus unsustainable
pressure on these forest resources. This is one of the causes of the decrease of pinewood area in
recent years. On the other hand, this dependence leads to extensive areas of forest monocultures
and, subsequently, increased risk of the forest fire propagation.
This work intends to stimulate the diversification of the wood products used in the
national industry of pulp and to provide a pulp with appropriate characteristics for incorporation
as fibber for paper reinforcement. At the level of forest producers, the use of this prime-material
would increase competitiveness among tree species and revitalization of less favoured rural areas
and, turning them into a possible solution for the lack of wood and an incentive to the
reforestation of these areas.
Wood from species Cupressus sempervirens and Cupressus arizonica, Acacia delbata
and Acacia melanoxylon were analysed. Content of extractives and of Klason lignin, fibre length
and coarseness were determined. Representative wood samples from Pinus pinaster grown in
Portugal and from Pinus sylvestris grown in Finland were used as reference. The wood from
Cupressus sempervirens showed lower Klason lignin and a fibre quality that appears to be more
adequate to pulp and paper.
Acacia species, with their relatively short, flexible and collapsible fibres, have potential
to produce papers with good relationships light scattering/tensile strength and smoothness/tensile
strength, at low energy consumption in refining. The studied acacia species showed slightly
better performance in pulping than the Eucalyptus globulus sample used as a comparison.
A indústria florestal produz resíduos com características e potenciais de utilização muito distintos. Por um lado, a queima de biomassa florestal para obtenção de energia conduz à produção de grandes quantidades de cinzas como produto final e, por outro lado, durante o processo de produção da pasta de papel e na sequência do tratamento por causticação é também produzido um resíduo em quantidades significativas. O objectivo deste trabalho foi avaliar o potencial fertilizante destes dois resíduos, ou seja, das cinzas provenientes da incineração de biomassa florestal e das cinzas provenientes da causticação da pasta de papel, resíduos provenientes da indústria florestal. Num ensaio em vasos estudou-se a resposta do azevém à aplicação de doses crescentes destes resíduos que corresponderiam à aplicação ao solo de 0, 0,5, 1, 3 e 5 toneladas por ha. Verificou-se que a cinza de biomassa florestal pode ser aplicada ao solo, não se observando efeitos negativos na produção ou propriedades do solo. Esta aplicação conduzirá ao fornecimento de alguns nutrientes, nomeadamente K e Ca. Em solos com relação Ca/Mg elevada aconselha-se a aplicação simultânea de Mg. O resíduo proveniente da causticação da pasta de papel, deve ser incorporado no solo com antecedência relativamente à sementeira devido à sua causticidade. Nas culturas plurianuais não deverá ser utilizado. Apresentou valor como correctivo alcalinizante, possuindo elevado teor em Na que conduziu a um aumento significativo da condutividade eléctrica e do Na de troca, não se aconselhando uma aplicação em quantidades superiores a 1 t/ha.
Comunicação apresentada no 5.º Congresso Florestal Nacional que decorreu em Viseu em Maio de 2005.
Trabalho apresentado em Abril de 2009, em Praga no Forestry, Wildlife and Wood Sciences for Society Development.
Aging systems of wine brandies have been a target of investigation to reduce the costs and aging time. In this study, the extractives and Klason lignin contents of wood fragments used in the aging of wine brandies in stainless steel tanks were evaluated. Two types of wood fragments, known as staves and tablets, and two wood botanical species, Limousin oak (Quercus robur L. from the Limousin region of France) and Portuguese chestnut (Castanea sativa Mill.), with heavy toasting levels were used. The wood extractive and Klason lignin contents were analyzed before and 30 months after the aging of wine brandy. The results showed that the chestnut wood presented the highest content of extractives, while the Klason and total lignin contents were higher in the oak wood. A highly significant effect from the tablets was found on the extractives and Klason lignin contents, while the soluble lignin content was more affected by the staves. Oxygenation of the wine brandies during the aging process negatively affected the release of extractives and lignin from the wood to the brandy, and therefore will impact the overall quality of the brandy.
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O conhecimento dos recursos existentes numa determinada região permite definir objectivos e implementar estratégias com vista à melhoria da qualidade de vida das respectivas populações. A valorização desses recursos possibilitará a dinamização da economia e o desenvolvimento sustentável dos mesmos. Este é um tema que tem merecido, nos últimos anos, a atenção das comunidades locais e regionais de algumas regiões do país. Reveste-se pois de extrema importância a definição e a operacionalização de políticas de desenvolvimento rural que contribuam, de forma eficaz, para uma inversão da tendência de diminuição demográfica que se tem vindo a observar nessas regiões. Contudo, existe um conjunto de aspectos espaciais e sociais que caracterizam o meio rural e lhe conferem uma identidade própria, específica e diferenciada, distinta da realidade urbana. É urgente valorizar os recursos locais, promovendo o desenvolvimento e a comunidade rural (Thirion e Cavaco, 2003).
Desde os tempos mais remotos que se tem assistido a uma forte relação do homem com as abelhas. A agricultura desempenhou, através dos tempos, uma importância crucial para o nosso país. Contudo, actualmente, é uma actividade em contínuo declínio, resultado em grande parte das políticas agrícolas implementadas e do êxodo das populações rurais para meios urbanos. Actualmente, ao contrário do que se assistiu noutros tempos, a terra e a agricultura assumem, muitas vezes, uma função de complementaridade de outras actividades numa perspectiva de pluriactividade. Esta situação, além de contribuir directa e/ou indirectamente para a economia familiar, reveste-se também de uma função de previdência, pois constitui um recurso “seguro” contra a aleatoriedade dos ciclos/vínculos profissionais, cada vez mais precários e incertos.
A prática apícola constitui uma das múltiplas actividades que podem originar outras fontes de rendimento complementar ou alternativo. O Município de Vila Velha de Ródão, região sobre a qual o estudo incidiu, apresenta boas condições edafo-climáticas para a prática apícola, apresentando uma floração sucessiva e diversificada, promovendo uma riqueza da flora melífera na região.
Por outro lado, a actividade apícola apresenta inúmeros benefícios indirectos associados à produção agrícola. Será impensável equacionar a competitividade da nossa agricultura sem a presença de uma actividade apícola que a suporte (GPP, 2007). Todavia, o maior valor que as abelhas acrescentam no ambiente consiste no inquestionável auxílio à polinização, na manutenção dos ecossistemas terrestres, no equilíbrio ecológico da flora e na preservação da biodiversidade (GPP, 2007; Murilhas, 2008).
O ordenamento do espaço físico constitui um instrumento necessário para que várias entidades, particularmente as municipais, o utilizem correctamente contribuindo com orientações compatíveis e congruentes ao nível da gestão territorial, para um aproveitamento integrado e economicamente sustentável do espaço rural (Carvalho et al., 2006; GPP, 2007).
No decurso deste trabalho foi efectuado um levantamento da flora apícola mais importante no concelho de Vila Velha de Ródão e elaboradas fichas técnicas para servir de ferramenta de apoio aos apicultores e à comunidade em geral. Procedeu-se, ainda, à identificação e referenciação geográfica dos apiários existentes no concelho de Vila Velha de Ródão, geograficamente inserido na zona controlada e sob gestão da Associação de Apicultores do Parque Natural do Tejo Internacional. Com este trabalho é promovida a possibilidade de cruzamento de informações e a melhoria na cartografia, utilizando os dados recolhidos através das análises de mel produzido e/ou de possíveis patologias que possam ocorrer nos apiários. Em síntese, pretende-se identificar as potencialidades deste território nacional ao nível da prática apícola, a fim de dinamizar o sector e fomentar um aproveitamento integrado do espaço rural.
Glucose and fructose are the most important monosaccharides in honey, these sugars combined in various forms comprise the di- and trisaccharide fractions of floral honey. Frutose/glucose ratio can influence the flavor of honey since fructose is sweeter than glucose. Honeys with higher fructose/glucose ratios remain liquid for longer periods. Several Chromatographic methods have been used to evaluate the sugar content of honey, although the Integrated Pulsed Amperometric Detection (IPAD) only recently became to be used.
In order to characterize the sugar content in honey from different botanical origins a Dionex ICS3000 ion chromatograph was used. Separation was performed in a column “CarboPacTM PA20 3x150mm”, with a precolumn “CarboPacTM PA20 3x30mm”. Electrochemical detector in Integrated Pulsed Amperometric Detection (IPAD) mode was used. The elution was performed with a gradient with two NaOH solutions (10 and 200 mM). Standard solutions of glucose, fructose and sucrose, were used to identify and quantify the individual sugar components in the honey samples.
The method showed a good separation between the compounds (resolution> 3.3 and more than 9000 theoretical plates). The response was linear in the range (0.05 to 1.00 mg/L for fructose and glucose and 0.01 to 0.20 mg/L for sucrose). The detection limits were 0.014 mg/L for glucose, 0.007 mg/L for fructose and 0.003 mg/L for sucrose.
Twenty six monofloral honey samples from Erica, Citrus, Lavandula and Eucalyptus were tested. 5,000 g of each honey sample was diluted to 1 mg/L and filtered with a 0.45 m polypropylene filter prior to HPLC analysis.
The results show that the fructose/glucose ratios are in accordance with the different honeys analyzed and the HPLC-IPAD is a good methodology to determine the sugar content in honey, with low solvent consumption and residues.
Two models were developed to evaluate total volume under and over-bark of Blackwood (Acacia
melanoxylon R. Br.) stand trees. By variance analysis regarding volume with and without bark it was
confirmed that trees age is responsible for 48 to 50% of its volumetric behaviour. Considered the
averages of those variables and regarding the three homogeneous groups of the studied sites, a single
model type was used (v=β1dβ2hβ3) for estimating volumes. The critical errors are between 72 and 195
dm3 under-bark, and 82 and 212dm3 over-bark. The model that uses sites as dummy variables to the
estimation of stand tree volumes is the same, and this method performs maximum expected errors
with values of 155 dm3 (under-bark) and 169dm3 (over-bark), to mean maximum volumes of 1362
and 1459 dm3 respectively. The use of dummy variables is a more expedite and rapid modelling
method, and its maximum expected errors perform lower values.
This work presents the determination of principal volatile compounds (acetaldehyde, ethyl acetate, methanol, 2-butanol, 1-propanol, 2-methyl-
1-propanol, 2-propen-1-ol, 1-butanol, 2-methyl-1-butanol and 3-methyl-1-butanol) in wine spirits, brandies and grape marc spirits by GC-FID.
The method was evaluated in terms of suitability of chromatographic system, accuracy, precision, linearity and detection and quantifi cation
limits. The method showed good accuracy for the majority of the compounds and it presented linearity and precision for all compounds.
Based on these results the method seems suitable for quality control of marc spirits and wine spirits.
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The maturation of wine brandies in wooden barrels cause many sensory and
physicochemical changes in these alcoholic beverages, namely its flavour modification.
Previous work (Caldeira et al. 2008) pointed out the most potent odourant compounds of
the wine aged brandies. Some of these compounds proceed from the distillate and others
are extracted from the wood.
In this study it was quantified, some odourless compounds, such as methanol and higher
alcohols and several odorant compounds in brandies aged in presence of two types of
wood fragments (staves and tablets), from two different kinds of woods (Limousin oak
wood and Portuguese chestnut wood), and compared with those found in the same with
brandy aged in wooden barrels. A taster panel have also profiled these brandies and
evaluated their overall quality.
The methanol and higher alcohols were quantified by GC-FID equipped with a fused silica
capillary column of polyethylene glycol according to the official method [NP 3263, 1990].
The odorant compounds were quantified by GC-FID and identified by GC-MS.
The results showed that the ageing system is the most discriminant factor, having a
significant effect on the level of several odourant compounds. The wood botanical species
affected few odourant compounds. The importance of odorant compounds was also
demonstrated by the high linear correlations between their contents and the intensity of
several sensory attributes.
The results show the possibility of using the chromatographic results as a tool to
discriminate brandies produced with different ageing technologies.
A tecnologia de envelhecimento tradicional, que consiste na colocação da aguardente vínica
em vasilhas de madeira durante vários anos, é uma técnica morosa e onerosa. Assim, têm vindo a ser
introduzidas e desenvolvidas novas técnicas, com o intuito de optimizar o processo e reduzir os custos.
Uma dessas novas técnicas consiste em introduzir pedaços de madeira (aparas, toros ou outras formas)
na bebida a envelhecer, condicionada em depósitos de inox. Têm sido realizados muitos estudos em
vinhos, mas em aguardentes a experimentação é escassa [1, 2].
Assim, este trabalho teve como objectivo avaliar a influência da utilização de alternativas ao
envelhecimento de aguardentes em vasilhas de madeira, na composição química das aguardentes
obtidas, dando particular atenção aos compostos odorantes provenientes da madeira.
Para tal, uma mesma aguardente vínica da Lourinhã foi submetida a um processo de envelhecimento,
com três formas de madeira: aguardente colocada em vasilha de madeira (V), aguardente colocada em
vasilha de inox com introdução de madeira sob a forma de dominós (D) e aguardente colocada em
vasilha de inox com introdução de madeira sob a forma de tábuas (T), tendo sido colhidas amostras de
aguardente, ao fim de 180 dias de envelhecimento, para análise e quantificação dos compostos
odorantes.
Os resultados obtidos mostram que a forma da madeira teve um efeito altamente significativo na
maioria dos compostos analisados. No caso dos compostos odorantes derivados da lenhina da madeira
(fenois voláteis e vanilina), os teores mais elevados foram encontrados nas aguardentes envelhecidas
na presença de fragmentos (dominós ou tábuas), enquanto para os compostos odorantes derivados das
hemiceluloses da madeira (ácido acético e aldeídos furânicos) os teores mais elevados foram
determinados nas aguardentes envelhecidas em vasilha de madeira.
Os resultados deste trabalho sugerem a possibilidade de diferenciação química das aguardentes, em
função da tecnologia de envelhecimento.
Comunicação oral da qual só está disponível a apresentação.
Neste trabalho foram utilizadas 30 amostras de mel monofloral de diferentes proveniências botânicas, entre as quais se destacam, a urze, o rosmaninho, a laranjeira, o eucalipto, a alfarrobeira e o castanheiro. O teor em fenóis totais foi determinado utilizando o método de Folin-Ciocalteu, usando o ácido gálico como padrão.
Pine oil can be obtained from α-pinene and is one of the constituents from gun-turpentine. Is a
natural product and is known for its insecticide, bactericide and fungicide proprieties.
In this study dry pinewood samples cut in radial section, were impregnated with pine oil and
limonene stabilised at room temperature.
The aim of this study was to incorporate ring width data into sawing yield strudies through simulation and tree modelling techniques. Results on data analysis measuring anual growth variation contribute also to the raw material characterisation.
In this study six wood species (birch, chestnut, oak, beech, poplar and eucalyptus) were analysed
separately. Lignin content, Polysaccharides content (cellulose and hemicelluloses), Yield,
Hexenuronic acids were evaluated for three cooking temperatures (140ºC, 150ºC and 160ºC) and
different cooking times. Common cooking conditions were applied and temperature program included
cold impregnation, a plateau at 110°C (2.5 hours) to perform initial delignification separately followed
by a second plateau at cooking temperature.
The results of PCA show that the almost all parameters (excluding hexenuronic acids) are well
correlated between them (total variance: 62%). For Eucalyptus and poplar species the hemicelluloses
content aren’t well correlated with the previously parameter, caused by the difference observed for the
higher temperatures. In some samples was observed that xylans are partially resistant and their
elimination is only partial (30 to 40%) in the early stage of cooking.
For the highest cooking time there were observed a significant difference between the three
temperatures studied.
Chestnut and oak wood species present a different behaviour compared with the other species, caused
by their similar anatomical and chemical structure. For the 160º of cooking temperature in the second
plateau was the poplar, beech and birch that present a different performance.
The main goal of this paper is to observe de differences of behaviour between six softwoods species
during the kraft cooking sequence, knowing that morphological, physicochemical and hygroscopic
characters are different. Six wood species (Scots pine, maritime pine, Aleppo pine, black pine,
Douglas fir and Spruce) were analysed separately.
Different parameters were evaluated (Lignin content, Polysaccharides content (cellulose and
hemicelluloses), Yield, Hexenuronic acids) and for each wood species three temperatures (150ºC,
160ºC and 170ºC) and different cooking times, allowing to study the behaviour of the wood species.
Common cooking conditions were applied and temperature program included cold impregnation, a
plateau at 110°C during 2.5 hours to perform initial delignification separately followed by a second
plateau at cooking temperature. Non-uniform cooking behaviour was observed; chestnut and oak
trees consumed much more caustic soda and had a lower yield in the initial phase of the cook. It was
possible conclude that in a genera way, the behaviour of the six softwoods is highly homogeneous, for
the three temperatures studied.
Data analysis was made with Principal component analysis (PCA) and ANOVA. The results of PCA
show that all parameters: Yield (Y), Klason lignin (L), cellulose content (C), and effective residual alkali
(EA) are well correlated. The cellulose content was negatively correlated with the other factors. The
hexenuronic acids (HA) and hemicelluloses content was well correlated witch other. The coking time in
the 2nd plateau influence all factors. Moreover, the three different temperatures are very similar they
present statically differences with Tukey’s test (P<0.05). For the highest cooking time all parameter
present lower values. The time on the 2nd plateau do not influence the yield and the delignification.
Utilização de análise multicritério para avaliação do potencial apícola.
Efeito dos polinizadores himenópteros em pomar de cereja.
A gestão eficaz da actividade apícola de uma
região só é possível se existir um mecanismo de
ordenamento dessa mesma actividade. Por outro
lado, os Sistemas de Informação Geográfica são uma
ferramenta indispensável para o planeamento e gestão
do território.
Os Concelhos do Crato e de Portalegre, apresentam
boas condições edafo-climáticas para a prática apícola,
apresentando uma floração sucessiva e diversificada,
o que conduz à riqueza da flora melífera na região
e à produção de um mel de excelente qualidade. A
área de estudo encontra-se na zona Controlada sob
gestão da Apilegre – Associação dos Apicultores do
Nordeste do Alentejo.
Neste contexto, pretende-se integrar os parâmetros
biofísicos, através de uma metodologia de análise
espacial, para elaborar uma carta de potencial apícola,
identificar possíveis conflitos na localização geográfica
de apiários e ainda representar a distribuição espacial
da ocorrência de doenças nas colmeias.
As cartas de zonas com potencial apícola e
as zonas interditas são elementos importantes no
apoio ao ordenamento apícola. Neste estudo foram
identificados nove apiários em zona interdita.
This work evaluated the sensorial and chemical modifications in
brandy aged in presence of two types of wood fragments in comparison with a brandy aged in
wooden barrels.
In the present work four olive groves were selected: two in organic agriculture and two in integrated
production. Olives were handpicked at two ripening stages and processed by a low-scale mill with a
working capacity of 0.05 tons h-1. Differences between olive oils were evaluated through a sensory
quantitative descriptive analysis (QDA) for positive attributes; moreover, some chemical parameters
that could be related with bitterness, like phenol content and the specific absorbance at 225 nm (K225),
were determined as well. Some analyses were also conducted with an Alpha MOS electronic nose
system, FOX 2000.
Este trabalho apresenta os resultados preliminares sobre a avaliação de metais
pesados no pólen de plantas que vegetam em locais com diferentes níveis de
poluição.
Foram recolhidas amostras de pólen diretamente das plantas em zonas onde havia
suspeita de contaminações diversas, nomeadamente junto a estradas, em solos com
alguma contaminação e num pomar. Foi também recolhido pólen apícola em zonas
consideradas mais poluídas.
Analisaram-se um total de 10 amostras e para cada uma delas foram determinadas as
concentrações em Cádmio(Cd), Crómio(Cr), Ferro(Fe), Zinco(Zn), Manganês(Mn),
Cobre(Cu) e Chumbo(Pb).
As amostras de pólen foram secas a 50ºC/24 horas e ulteriormente mineralizadas com
uma mistura de HNO3 e H2O2. As concentrações dos metais referidos foram
determinadas por espectrometria de emissão de plasma (ICP-OES).
Nas amostras recolhidas junto a uma estrada, num pomar e num terreno perto de uma
antiga lixeira verificaram-se níveis elevados de Fe, Mn e Pb enquanto que para os
restantes metais analisados os níveis estavam dentro dos valores de referência para o
pólen.
Estes resultados preliminares fazem parte de um estudo mais completo onde se
pretende correlacionar os níveis de metais pesados no pólen com os contaminantes
presentes nos solos, e para já foi possível verificar que pode ser assim contaminado
por eles dependendo do meio onde vegetam as plantas, confirmando a hipótese de
pode ser usado como marcador ambiental.
