I am currently Assistant Professor with habilitation at the Chemistry Department of the University of Trás-os-Montes e Alto Douro in the field of Food Chemistry and Analytical Chemistry. I am an integrated member of the Chemistry Research Centre - Vila Real since 2005, being the Principal Investigator of the Food Chemistry and Biochemistry Research Line and Vice- director of the Chemistry Research Centre - Vila Real. I am the author of more than 100 international peer reviewed papers and holder of 9 national and international patent applications. I have coordinated 5 projects as the principal investigator and more 5 projects as participant. My current research goals are Food Quality and Nutraceuticals, including gluten detoxification for celiac patients, wine quality and safety and the search for natural sources of nutraceuticals, mainly phenolic compounds.
Chelonus elaeaphilus Silvestri (Hymenoptera: Braconidae) é um parasitóide específico da traça-da-... more Chelonus elaeaphilus Silvestri (Hymenoptera: Braconidae) é um parasitóide específico da traça-da-oliveira, Prays oleae (Bernard), que, em Portugal, pode originar taxas de parasitismo próximas de 80%. Com este estudo, pretendeu-se contribuir para conhecer as possibilidades oferecidas por 18 espécies de plantas da flora espontânea do olival, na melhoria do desempenho de C. elaeaphilus, ao facultar-lhes açúcar, na forma de néctar. Analisou-se o efeito, de quatro açúcares do néctar (frutose, glucose, maltose e sacarose), na longevidade do parasitóide. Avaliou-se a possibilidade teórica de acesso do insecto ao néctar das espécies de plantas e analisou-se a sua composição em açúcar. A longevidade das fêmeas foi superior nos indivíduos alimentados com sacarose e glucose, comparativamente aos que consumiram maltose e frutose. Verificou-se que o parasitóide consegue aceder ao néctar das plantas estudadas, com excepção das Asteráceas. Os néctares analisados continham predominantemente glucose...
Mushroom production generates large amounts of by-products whose disposal creates environmental p... more Mushroom production generates large amounts of by-products whose disposal creates environmental problems. The high abundance of biological active non-starch polysaccharides in mushroom cell walls makes these by-products attractive for dietary fiber-based ingredient (DFI) production. Traditional methods of dietary fiber preparation didn’t allow to obtain a DFI with suitable chemical and functional properties. In this work a simple and environmentally friendly method was developed and optimized for DFI production using a central composite design with treatment time, hydrogen peroxide and sodium hydroxide concentration as factors and chemical composition, chromatic and functional properties as dependent variables. The chemical composition of the DFI was strongly influenced by the process parameters and its functional and color properties were dependent on its fiber and protein content, respectively. The method developed is simple, uses food grade and low-cost reagents and procedures yi...
Sugarcane honey (SCH) is one of the Madeira Island products par excellence and it is now popular ... more Sugarcane honey (SCH) is one of the Madeira Island products par excellence and it is now popular worldwide. Its sui generis and peculiar sensory properties, explained by a variety of volatile compounds including furanic derivatives (FDs), arise mainly from manufacturing and storage conditions. A simple high-throughput approach based on semi-automatic microextraction by packed sorbent (MEPS) combined with ultra-high performance liquid chromatography (UHPLC) was developed and validated for identification and quantification of target FDs in sugarcane honey. A Quality-by-Design (QbD) approach was used as a powerful strategy to optimize analytical conditions for high throughput analysis of FDs in complex sugar-rich food matrices. The optimum point into MEPS-Method Operable Design: Region (MODR) was obtained with R-CX sorbent, acetonitrile (ACN) as elution solvent, three loading cycles and 500μL of sample volume. The optimum point into UHPLC-MODR was obtained with a CORTECS column operati...
Ammonia caramels are the most common antioxidant colour agent used in bakery formulations, althou... more Ammonia caramels are the most common antioxidant colour agent used in bakery formulations, although their high sugars content. An alternative could be coffee melanoidins, which are brown coloured compounds with antioxidant properties, readily available from instant coffee. However, high caffeine content is limiting its direct application. To evaluate the possibility of obtaining coloured melanoidin-rich, sugars- and caffeine-poor fractions from instant coffee, in this work, simple procedures based on their ethanol insolubility (fraction EtPp) or retention by ultrafiltration (fraction HWSn) were exploited. Melanoidins incorporation into biscuits formulation (amounts of 1, 5 and 10% w/w related to flour content) resulted in acceptable coloured products with higher antioxidant activity. The biscuits supplemented with 1% EtPp or HWSn had a low caffeine content. The caffeine of one espresso coffee was equivalent to 130 biscuits containing EtPp and 31 biscuits containing HWSn. Besides, bo...
The phytochemical characterization, antioxidant activity and in vitro cytotoxicity against human ... more The phytochemical characterization, antioxidant activity and in vitro cytotoxicity against human cancer cell lines of Geranium molle L. extracts are reported for the first time.
Journal of agricultural and food chemistry, Jan 8, 2016
Three mixtures containing different molar proportions of (β1→4)-D-mannotriose and (α1→5)-L-arabin... more Three mixtures containing different molar proportions of (β1→4)-D-mannotriose and (α1→5)-L-arabinotriose, oligosaccharides structurally related to coffee polysaccharides (galactomannans and arabinogalactans), were roasted at 200 °C for different periods. Electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (ESI-MSn) analyses of labeled (18O) and unlabeled samples allowed identification of non-hybrid oligosaccharides, but also hybrid oligosaccharides composed by both hexose and pentose units. The identification of hybrid oligosaccharides allowed us to infer the occurrence of non-enzymatic transglycosylation reactions involving both oligosaccharides in the starting mixtures. Also, it was observed that using different proportion of the oligosaccharides in the starting mixtures and extent of the thermal treatment lead to a variation in the composition of the compounds formed. These results have led to the conclusion that, depending on the distribution of the p...
Chelonus elaeaphilus Silvestri (Hymenoptera: Braconidae) é um parasitóide específico da traça-da-... more Chelonus elaeaphilus Silvestri (Hymenoptera: Braconidae) é um parasitóide específico da traça-da-oliveira, Prays oleae (Bernard), que, em Portugal, pode originar taxas de parasitismo próximas de 80%. Com este estudo, pretendeu-se contribuir para conhecer as possibilidades oferecidas por 18 espécies de plantas da flora espontânea do olival, na melhoria do desempenho de C. elaeaphilus, ao facultar-lhes açúcar, na forma de néctar. Analisou-se o efeito, de quatro açúcares do néctar (frutose, glucose, maltose e sacarose), na longevidade do parasitóide. Avaliou-se a possibilidade teórica de acesso do insecto ao néctar das espécies de plantas e analisou-se a sua composição em açúcar. A longevidade das fêmeas foi superior nos indivíduos alimentados com sacarose e glucose, comparativamente aos que consumiram maltose e frutose. Verificou-se que o parasitóide consegue aceder ao néctar das plantas estudadas, com excepção das Asteráceas. Os néctares analisados continham predominantemente glucose...
Mushroom production generates large amounts of by-products whose disposal creates environmental p... more Mushroom production generates large amounts of by-products whose disposal creates environmental problems. The high abundance of biological active non-starch polysaccharides in mushroom cell walls makes these by-products attractive for dietary fiber-based ingredient (DFI) production. Traditional methods of dietary fiber preparation didn’t allow to obtain a DFI with suitable chemical and functional properties. In this work a simple and environmentally friendly method was developed and optimized for DFI production using a central composite design with treatment time, hydrogen peroxide and sodium hydroxide concentration as factors and chemical composition, chromatic and functional properties as dependent variables. The chemical composition of the DFI was strongly influenced by the process parameters and its functional and color properties were dependent on its fiber and protein content, respectively. The method developed is simple, uses food grade and low-cost reagents and procedures yi...
Sugarcane honey (SCH) is one of the Madeira Island products par excellence and it is now popular ... more Sugarcane honey (SCH) is one of the Madeira Island products par excellence and it is now popular worldwide. Its sui generis and peculiar sensory properties, explained by a variety of volatile compounds including furanic derivatives (FDs), arise mainly from manufacturing and storage conditions. A simple high-throughput approach based on semi-automatic microextraction by packed sorbent (MEPS) combined with ultra-high performance liquid chromatography (UHPLC) was developed and validated for identification and quantification of target FDs in sugarcane honey. A Quality-by-Design (QbD) approach was used as a powerful strategy to optimize analytical conditions for high throughput analysis of FDs in complex sugar-rich food matrices. The optimum point into MEPS-Method Operable Design: Region (MODR) was obtained with R-CX sorbent, acetonitrile (ACN) as elution solvent, three loading cycles and 500μL of sample volume. The optimum point into UHPLC-MODR was obtained with a CORTECS column operati...
Ammonia caramels are the most common antioxidant colour agent used in bakery formulations, althou... more Ammonia caramels are the most common antioxidant colour agent used in bakery formulations, although their high sugars content. An alternative could be coffee melanoidins, which are brown coloured compounds with antioxidant properties, readily available from instant coffee. However, high caffeine content is limiting its direct application. To evaluate the possibility of obtaining coloured melanoidin-rich, sugars- and caffeine-poor fractions from instant coffee, in this work, simple procedures based on their ethanol insolubility (fraction EtPp) or retention by ultrafiltration (fraction HWSn) were exploited. Melanoidins incorporation into biscuits formulation (amounts of 1, 5 and 10% w/w related to flour content) resulted in acceptable coloured products with higher antioxidant activity. The biscuits supplemented with 1% EtPp or HWSn had a low caffeine content. The caffeine of one espresso coffee was equivalent to 130 biscuits containing EtPp and 31 biscuits containing HWSn. Besides, bo...
The phytochemical characterization, antioxidant activity and in vitro cytotoxicity against human ... more The phytochemical characterization, antioxidant activity and in vitro cytotoxicity against human cancer cell lines of Geranium molle L. extracts are reported for the first time.
Journal of agricultural and food chemistry, Jan 8, 2016
Three mixtures containing different molar proportions of (β1→4)-D-mannotriose and (α1→5)-L-arabin... more Three mixtures containing different molar proportions of (β1→4)-D-mannotriose and (α1→5)-L-arabinotriose, oligosaccharides structurally related to coffee polysaccharides (galactomannans and arabinogalactans), were roasted at 200 °C for different periods. Electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (ESI-MSn) analyses of labeled (18O) and unlabeled samples allowed identification of non-hybrid oligosaccharides, but also hybrid oligosaccharides composed by both hexose and pentose units. The identification of hybrid oligosaccharides allowed us to infer the occurrence of non-enzymatic transglycosylation reactions involving both oligosaccharides in the starting mixtures. Also, it was observed that using different proportion of the oligosaccharides in the starting mixtures and extent of the thermal treatment lead to a variation in the composition of the compounds formed. These results have led to the conclusion that, depending on the distribution of the p...
Uploads
Papers by Fernando Nunes