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Projeto de investigação
Linking Landscape, Environment, Agriculture and Food
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Microalgae biomass as an additional ingredient of gluten-free bread: Dough rheology, texture quality and nutritional properties
Publication . Khemiri, Sheyma; Khelifi, Nadia; Nunes, Maria Cristiana; Ferreira, Alice; Gouveia, Luísa; Smaali, Smaali; Raymundo, Anabela
Microalgae have been widely used as a source of functional ingredients such as pigments, antioxidants, vitamins,
and omega-3 polyunsaturated fatty acids. They also represent a promising alternative source of protein. The
objective of this study was to evaluate the impact of the addition of two green microalgae species
(Nannochloropsis gaditana L2 and Chlamydomonas sp. EL5) on the techno-functional and nutritional properties of
gluten-free bread. Microalgae biomass was added in the amounts of 1.0 and 3.0 g/100 g of flour. The behavior of
the dough during the mixing as well as the physicochemical properties of the prepared breads were investigated.
Gluten-free bread with N. gaditana L2 and Chlamydomonas sp. EL5 presented significantly higher protein and
higher levels of lipids and ash, compared with the control bread. The incorporation of 3% microalgae biomass
revealed a 100% increase in iron and calcium contents. The fatty acid profile of supplemented bread changed in
a species-specific manner with a particular increase in linolenic acid (18:3 ω3) and a decrease in ω3/ω6 ratio.
Besides, due to its original biochemical composition, mainly the highly protein content, microalgae incorporation
was found to bring an overall structuring effect on the gluten-free bread texture. However, the
dough mixing properties were not affected significantly by microalgae addition. A significant change in color
was recorded in doughs, breads, crusts and crumbs. This was caused by the presence of pigment in microalgae
biomass, which turned into more intense green-yellow tonalities. A sensory analysis revealed that the supplemented
breads scored highest for nearly all the sensory parameters with the 3% N. gaditana L2 bread as the
preferred one in terms of global appreciation. This innovative approach gives new insights of the possibility of
improving gluten-free products, structurally and nutritionally, using only microalgae as a natural and a sustainable
food ingredient
Physiological response of Cistus salviifolius L. to high arsenic concentrations
Publication . Carvalho, Luisa C; Vieira, Cláudia; Abreu, Maria Manuela; Magalhães, Maria Clara F.
Arsenic is a trace element found in the environment which can be particularly toxic to living organisms. However, some plant species such as those of the genus Cistus are able to grow in soils with high As concentrations and could be used in the sustainable rehabilitation of mining areas 19 through phytostabilization. In this work, the growth and the physiological response of Cistus salviifolius L. to As induced oxidative stress at several concentrations (reaching 30 mg L-1) in an hydroponic system were evaluated for 30 days. Several growth parameters, chlorophyll content, chemical composition, one indicator of oxidative stress (H2O2) and two of the major anti-oxidative metabolites (ascorbate and glutathione) were analyzed.
The toxic effect of As was better perceived in the plants submitted to treatments with concentrations of 20 and 30 mg As L-1. Plants subjected to these treatments had higher concentration of As in roots and shoots. The concentrations of Ca, Mg, K and Fe in the plants, as well as a large part of the evaluated growth parameters were also affected. Arsenic did not interfere with the ability of the plant to perform photosynthesis, as there were no significant differences in the contents of chlorophyll a, b and total between the different treatments. Plants from all treatments accumulated higher amount of As in roots than in shoots, and it was also in the roots that the concentrations of H2O2, AsA and GSH were higher. Cistus salviifolius showed high tolerance to As up to the concentration of 5 mg L-1, which makes it a species with high potential to be used in the phytostabilization of soils contaminated with As and presenting high concentrations of the element in the soil solution.
Mechanical pruning in non-irrigated vineyards: effects on yield and grape composition of cultivar ‘Syrah’ (Vitis vinifera L.)
Publication . Botelho, M.; Cruz, A.; Silva, E.B.; Mexia, A.; Ricardo-da-Silva, Jorge M.; Castro, R.; Ribeiro, Henrique
The effect of mechanical pruning on vine performance and wine quality was evaluated from 2012 until 2015. Two trial fields, with a randomized complete block design, were established on already existing ‘Syrah’ vineyards in Quinta do Côro and Quinta do Gradil, located in Tejo and Lisboa wine regions respectively. Mechanical pruning (MEC) was simulated by trimming all shoots to a 15 cm square around the cordon. Manual pruning (MAN) treatment was subjected to a traditional spur pruning. MEC tended to increase water consumption due to the higher proportion of exposed leaf area, since the total leaf area per vine was not different from MAN. The transpiration and photosynthetic rates were tendentially lower in MEC, indicating an adaptation to more stressful conditions. Yield was higher in MEC, while the individual shoot vigour and the total amount of pruning wood were lower in MEC. These results led to higher values of the Ravaz index in this treatment, reflecting changes in the partitioning of carbohydrates that were redirected from vegetative to reproductive growth. Total dry matter production (DMP) was mainly not affected by the pruning system, even in years with lower water availability. In 2014, when water was not a limitative factor, the total dry matter production was higher in MEC. The DMP in MEC was not reduced along the trial, suggesting that reserves accumulation have not been restricted. The grape composition, analyzed in 2013 and 2014, has not been significantly affected, with the exception of the total soluble solids content (TSS) and the pH, in 2014, which were lower in MEC. The results indicate that mechanical pruning is a reliable instrument to improve vine performance in non-irrigated vineyards, increasing yield without quality loss, even in dry years
The effects of improving low dietary protein utilization on the proteome of lamb tissues
Publication . Ribeiro, D.M.; Planchon, S.; Leclercq, C.C.; Dentinho, M.T.P.; Bessa, R.J.B.; Santos-Silva, J.; Paulos, K.; Jerónimo, E.; Renault, J.; Almeida, A.M.
Cistus ladanifer L. is a common shrub endemic to the Mediterranean region with high levels of condensed tannins (CT). CT form complexes with dietary protein resisting microbial degradation in the rumen, which enhances dietary protein utilization in ruminant diets. The objective of this study was to evaluate the utilization of CT in the diet of lambs on the proteomes of muscle, hepatic and adipose tissues.
Twenty-four Merino Branco ram lambs were randomly allocated to three treatments (n = 8): C – control (160 g crude protein (CP)) per kg DM, RP – reduced protein (120 g CP/kg DM); and RPCT – reduced protein (120 g CP/kg DM) treated with CT extract. At the end of the trial, lambs were slaughtered and the longissimus lumborum muscle, hepatic and peri-renal adipose tissues sampled. A two-way approach was used for proteomic analysis: 2D-DIGE and nanoLC-MS.
In the muscle, C lambs had lower abundance proteins that partake in the glycolysis pathway than the lambs of other treatments. Control lambs had lower abundance of Fe-carrying proteins in the hepatic tissue than RP and RPCT lambs. The latter lambs had highest abundance of hepatic flavin reductase. In the adipose tissue, C lambs had lowest abundance of fatty-acid synthase
Prediction of crop coefficients from fraction of ground cover and height. Background and validation using ground and remote sensing data
Publication . Pereira, L.S.; Paredes, Paula; Melton, F.; Johnson, L.; Wang, T.; López-Urrea, R.; Cancela, J.J.; Allen, R.G.
The current study aims at reviewing and providing advances on methods for estimating and applying crop coefficients
from observations of ground cover and vegetation height. The review first focuses on the relationships between single
Kc and basal Kcb and various parameters including the fraction of ground covered by the canopy (fc), the leaf area index
(LAI), the fraction of ground shaded by the canopy (fshad), the fraction of intercepted light (flight) and intercepted
photosynthetic active radiation (fIPAR). These relationships were first studied in the 1970’s, for annual crops, and later,
in the last decennia, for tree and vine perennials. Research has now provided a variety of methods to observe and
measure fc and height (h) using both ground and remote sensing tools, which has favored the further development of Kc
related functions. In the past, these relationships were not used predictively but to support the understanding of
dynamics of Kc and Kcb in relation to the processes of evapotranspiration or transpiration, inclusive of the role of soil
evaporation. Later, the approach proposed by Allen and Pereira (2009), the A&P approach, used fc and height (h) or LAI
data to define a crop density coefficient that was used to directly estimate Kc and Kcb values for a variety of annual and
perennial crops in both research and practice. It is opportune to review the A&P method in the context of a variety of
studies that have derived Kc and Kcb values from field measured data with simultaneously observed ground cover fc and
height. Applications used to test the approach include various tree and vine crops (olive, pear, and lemon orchards and
vineyards), vegetable crops (pea, onion and tomato crops), field crops (barley, wheat, maize, sunflower, canola, cotton
and soybean crops), as well as a grassland and a Bermudagrass pasture. Comparisons of Kcb values computed with the A
&P method produced regression coefficients close to 1.0 and coefficients of determination≥0.90, except for orchards.
Results indicate that the A&P approach can produce estimates of potential Kcb, using vegetation characteristics alone,
within reasonable or acceptable error, and are useful for refining Kcb for conditions of plant spacing, size and density
that differ from standard values. The comparisons provide parameters appropriate to applications for the tested crops.
In addition, the A&P approach was applied with remotely sensed fc data for a variety of crops in California using the
Satellite Irrigation Management Support (SIMS) framework. Daily SIMS crop ET (ETc-SIMS) produced Kcb values using
the FAO56 and A&P approaches. Combination of satellite derived fc and Kcb values with ETo data from Spatial CIMIS
(California Irrigation Management Information System) produced ET estimates that were compared with daily actual
crop ET derived from energy balance calculations from micrometeorological instrumentation (ETc EB).Results produced
coefficients of regression of 1.05 for field crops and 1.08 for woody crops, and R2 values of 0.81 and 0.91, respectively.
These values suggest that daily ETc-SIMS -based ET can be accurately estimated within reasonable error and that the A&P
approach is appropriate to support that estimation. It is likely that accuracy can be improved via progress in remote
sensing determination of fc. Tabulated Kcb results and calculation parameters are presented in a companion paper in this
Special Issue
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Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
6817 - DCRRNI ID
Número da atribuição
UID/AGR/04129/2013