A elevada perecibilidade é uma característica dos cogumelos consumidos em fresco. Assim, torna-se... more A elevada perecibilidade é uma característica dos cogumelos consumidos em fresco. Assim, torna-se necessária a aplicação de tecnologias eficazes de conservação, permitindo a sua preservação e protegendo, simultaneamente, a sua composição química e valor nutricional. A secagem, apesar de ser uma técnica bastante utilizada, permite o desenvolvimento de bactérias e fungos que têm a capacidade de sobreviver por longos períodos de tempo em alimentos secos; provoca ainda a perda de alguns nutrientes e promove reações enzimáticas e não enzimáticas que levam ao escurecimento do alimento e, também, à oxidação de lípidos e vitaminas [1]. A irradiação surge, assim, como uma alternativa de conservação de alimentos, garantindo a sua qualidade e estando a sua utilização regulamentada na U.E. para vários produtos alimentares [2]. Neste trabalho, avaliaram-se os efeitos da irradiação com feixe de eletrões e do tempo de armazenamento nos parâmetros nutricionais e químicos de amostras silvestres de Macrolepiota procera (Scop.) Singer, previamente submetidas a secagem (em estufa a 30 ºC). A irradiação com feixe de eletrões (doses 2, 6 e 10 kGy) foi efetuada no INCT- Instituto Nuclear de Química e Tecnologia, em Varsóvia, na Polónia e as análises foram efetuadas ao longo do período de armazenamento (0, 6 e 12 meses). Todos os resultados foram comparados com amostras controlo (não irradiadas). O valor nutricional determinou-se de acordo com os procedimentos oficias de análise de alimentos, tendo-se obtido também os perfis em ácidos gordos, tocoferóis, mono e oligossacáridos por técnicas cromatográficas [1]. A irradiação evidenciou maior capacidade em manter o perfil nutricional e químico, relativamente ao tempo de armazenamento. Efetivamente, este último teve um efeito maior em todos os parâmetros analisados, com exceção dos ácidos gordos, que sofreram alterações significativas tanto com as doses aplicadas como com o tempo de armazenamento. A irradiação por feixe de eletrões pode ser considerada uma técnica adequada para a conservação e preservação de cogumelos por períodos de longa duração, ao mesmo tempo que atenua as alterações provocadas pelo tratamento de secagem
Antitumor, antimicrobial and antioxidant activities of basil were studied, along with its charact... more Antitumor, antimicrobial and antioxidant activities of basil were studied, along with its characterization in phenolic compounds, organic acids and soluble sugars. The results placed basil as a valuable candidate for functionalization and conservation of food products, maintaining their nutritional properties, while increasing their shelf life and potential health effects. The basil leaves were then incorporated in ''Serra da Estrela Cheese", either in its dehydrated form or as a decoction. The cheeses were then subject to a nutritional evaluation, being characterized for their fatty acids, minerals and CIE color parameters. To assess the combined effects of plant incorporation and storage time, a 2-way ANOVA was used to process the results, further analysed through a linear discriminant analysis. Overall, basil leaves provided antioxidant activity to the cheeses, reduced the moisture, and preserved the unsaturated fatty acids and proteins. Comparing both incorporation types, the decoctions had a higher functionalizing and conservative effect.
The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial ac... more The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial activity of mushroom species (Boletus edulis, Hydnum repandum, Macrolepiota procera and Russula delica) differently processed (fresh, dried, freeze) were evaluated. : Clinical isolates with different resistance profiles from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal, were used as target microorganisms. The mushrooms antimicrobial activity did not suffer significant changes that might compromise applying irradiation as a possible mushroom conservation technology. Conclusions: 2 kGy dose (independently of using gamma-rays or electron-beams) seemed to be the most suitable choice to irradiate mushrooms. This study provides important results in antimicrobial activity of extracts prepared from irradiated mushroom species.
Sterols are important molecules in the unsaponifiable fraction of several matrices. Ergosterol, w... more Sterols are important molecules in the unsaponifiable fraction of several matrices. Ergosterol, which is an important vitamin D 2 precursor, is clearly the main sterol in mushrooms. Herein, an analytical method for ergosterol determination in cultivated and wild mushrooms was developed using high performance liquid chromatography coupled to ultraviolet detection. The chromatographic separation was achieved in a Inertsil 100A ODS-3 reverse phase column using an isocratic elution with acetonitrile:methanol (70:30, v:v) at a flow rate of 1 mL/min. Different extraction methodologies were tested, using n-hexane, methanol:dichloromethane (75:25, v:v) or chloroform:methanol (20:10, v:v). The method was optimized using Fistulina hepatica and proved to be reproductive and accurate. Ergosterol was the most abundant sterol by a greater extent in all mushrooms. In general, the cultivated species showed higher contents, mainly Agaricus bisporus and Lentinus edodes. Among wild species, Boletus edulis was the mushroom with the highest content in ergosterol. Results were expressed in fat content, dry weight and fresh weight bases. The assessment of ergosterol amounts might be very useful due to the bioactive potential that has been attributed to this molecule and its derivatives.
Trends in Food Science and Technology, Apr 1, 2016
Background: The well-known correlation between diet and physiology demonstrates the great possibi... more Background: The well-known correlation between diet and physiology demonstrates the great possibilities of food to maintain or improve our health, increasing the interest in finding new products with positive physiological effects. Nowadays, one of the top research areas in Food Science and Technology is the extraction and characterization of new natural ingredients with biological activity that can be further incorporated into a functional food, contributing to consumer's well-being. Furthermore, there is a high demand for effective encapsulation methodologies to preserve all the characteristics of bioactive compounds until the physiological action site is reached. Scope and approach: In this review, the relevance of developing standard approaches for the extraction of the highly diverse bioactive compounds was described, as it defines the suitability of the following steps of separation, identification and characterization. Special attention was also dedicated to the encapsulation techniques used on hydrophilic and/or lipophilic compounds (e.g., emulsification, coacervation, supercritical fluid, inclusion complexation, emulsification-solvent evaporation and nanoprecipitation). Key findings and conclusions: Some useful conclusions regarding the selection of the best extraction methodology (Soxhlet extraction, ultrasound-assisted extraction, supercritical fluid extraction, accelerated solvent extraction, or shake extraction) were achieved, considering important aspects such as cost, required technical skills, extract integrity, green chemistry principles, solvent type, sample size, pH, temperature and pressure. In addition, this comprehensive review allowed defining the best protective approach to solve the limitations related to the extremely low absorption and bioavailability of bioactive phytochemicals, overcoming problems related to their low solubility, poor stability, low permeability and metabolic processes in the GI tract.
Agradecimentos: Ministerio da Agricultura (PRODER/FEADER/UE, projecto AROMAP), pelo suporte finan... more Agradecimentos: Ministerio da Agricultura (PRODER/FEADER/UE, projecto AROMAP), pelo suporte financeiro do trabalho e E. Pereira; Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) pelo suporte financeiro ao CIMO (PEst-OE/AGR/UI0690/2014) e L. Barros (SFRH/BPD/107855/2015); Prof. A. Chmielewski, director do INCT, Polonia, e Dr. A. Rafalski pelas irradiacoes com feixe de electroes
Ministerio da Agricultura, Portugal (Projeto PRODER/FEADER/EU no. 53514), pelo financiamento do t... more Ministerio da Agricultura, Portugal (Projeto PRODER/FEADER/EU no. 53514), pelo financiamento do trabalho e pela bolsa atribuida a E. Pereira; a Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), pelo financiamento do CIMO (PEst-OE/AGR/UI0690/2014) e CTN (RECI/AAG-TEC/0400/2012) e pelas bolsas de pos-doutoramento de L. Barros (BPD/107855/2015) e J.C.M. Barreira (BPD/72802/2010). Ao Prof A. Chmielewski, Diretor do INCT, e ao Dr. A. Rafalski, pelo trabalho de irradiacao por feixe de eletroes.
Tree nuts have long been recognized as sources of nutrients in healthy diets, such as the Mediter... more Tree nuts have long been recognized as sources of nutrients in healthy diets, such as the Mediterranean one, besides being increasingly promoted as healthy ingredients for different food applications. In this chapter, recent literature on compositional features of almond, chestnut, hazelnut, and walnut will be comprehensively reviewed. We provide information regarding the profiles of the most relevant macronutrients and micronutrients, discussing the potential nutritional and health effects of these nuts and also focusing on the laboratory methodologies employed. An overview of major compounds in each species is provided throughout the text, covering nuts grown in various regions. This chapter is mainly focused on the edible parts of the selected nuts, so the presented results relate exclusively to the kernels, not other botanical parts, such as leaves, flowers or husks.info:eu-repo/semantics/publishedVersio
Vitamins and mineral elements are among the most important phytochemicals due to their important ... more Vitamins and mineral elements are among the most important phytochemicals due to their important role in the maintenance of human health. Despite these components had already been studied in different plant species, their full characterization in several wild species is still scarce. In addition, the knowledge regarding the in vivo effects of phytochemicals, particularly their bioaccessibility, is still scarce. Accordingly, a membrane dialysis process was used to simulate gastrointestinal conditions in order to assess the potential bioaccessibility of mineral elements in different preparations of Achillea millefolium (yarrow), Laurus nobilis (laurel) and Taraxacum sect. Ruderalia (dandelion). The retention/passage dynamics was evaluated using a cellulose membrane with 34 mm pore. Dandelion showed the highest levels of all studied mineral elements (except zinc) independently of the used formulations (dried plant or infusion), but yarrow was the only species yielding minerals after the dialysis step, either in dried form, or as infusion. In fact, the ability of each evaluated element to cross the dialysis membrane showed significant differences, being also highly dependent on the plant species. Regarding the potential use of these plants as complementary vitamin B 9 sources, the detected values were much lower in the infusions, most likely due to the thermolability effect.
The food industry is always seeking innovative approaches to maintain consumers' interest and inc... more The food industry is always seeking innovative approaches to maintain consumers' interest and increase their awareness towards the healthiness of diets. Therefore, much interest has been given to natural food additives, namely colourants. In this work, a bilberry extract was primarily characterized in terms of anthocyanin compounds by UPLC-DAD-ESI/MSn, and its colouring capacity was further compared with a synthetic anthocyanin colourant (E163) in different yogurt formulations. The prepared samples were evaluated in different periods (0 and 7 days) for nutritional profile, individual fatty acids, soluble sugars and external colour to determine the effects of each additive. Overall, the major anthocyanin compounds in bilberry were malvidin glycoside and delphinidin glycoside derivatives. With regard to the prepared yogurts, all samples maintained the nutritional profile, individual fatty acids and soluble sugars, independent of storage time. Nonetheless, bilberry extracts showed lower colouring capacity when compared to that of E163, despite the higher stability of bilberry extract throughout the storage time, when compared to that of E163. Furthermore, another advantage of this natural extract is that it has potential bioactive properties that can be conferred to foods, due to their high content of bioactive compounds, such as anthocyanins.
The effects of gamma irradiation on Aloysia citrodora, Melissa officinalis, Melittis melissophyll... more The effects of gamma irradiation on Aloysia citrodora, Melissa officinalis, Melittis melissophyllum and Mentha piperita were previously evaluated. Herein, the same species were treated with electron-beam irradiation (EB) and the same parameters were evaluated. Instead of presenting absolute values for each studied parameter, data were evaluated as percentage of induced variation. Besides the newly obtained results, data from a previous work was recalled and normalized in the same manner. Several examples of percentage variations specific to a plant species or irradiation condition were found. Nevertheless, it was not possible to identify unequivocal trends. Even so, when evaluated in an integrative way, the parameters with highest discriminating ability among irradiation conditions or plant species were fatty acids and bioactive indicators. Comparing the effects of gamma and EB irradiations, it might be concluded that the most suitable solution to irradiate aromatic plants would be EB, independently of the used dose.
Innovative Food Science and Emerging Technologies, Aug 1, 2016
Wild plants are widely recognized as high-potential sources of several bioactive compounds. Never... more Wild plants are widely recognized as high-potential sources of several bioactive compounds. Nevertheless, these natural matrices require effective decontamination steps before they might be considered for different industrial purposes. Irradiation techniques are being progressively acknowledged as feasible conservation methodologies, either for their high decontamination effectiveness, as well as for their innocuousness on most chemical and bioactive parameters of the material to be treated. Arenaria montana L. (Caryophyllaceae) is recognized for its phytochemical richness, having a relevant geographical distribution in the Southern Europe. Herein the effects of irradiation (gamma and electron beam up to 10 kGy) were evaluated by comparing the nutritional, chemical and antioxidant profiles in A. montana extracts. In general, the assayed parameters showed statistically significant variations in response to irradiation treatment. Furthermore, the performed LDA allowed identifying the antioxidant indicators as the most affected parameters in irradiated samples, especially when using the 10 kGy dose and e-beam irradiation.
Owing to the overall increase in herbal infusions' consumption, there's a progressively higher ne... more Owing to the overall increase in herbal infusions' consumption, there's a progressively higher need of suitable plant material, as well as adequate conservation techniques to maintain its quality. Among, the available technologies, irradiation is gaining interest as a feasible preservation method. In line with this approach, this wok was designed to evaluate the effects of electron-beam and gamma irradiation over the phenolic profiles of two plant species Melissa officinalis L. (LB) and Melittis melissophyllum L. (BB). Individual phenolics were characterized by high-performance liquid chromatography coupled to a diode array detector and a mass spectrometer (HPLC-DAD-ESI/MS). Irradiated samples showed a general increase in individual phenolic contents, especially in lithospermic acid A in LB and 5-O-caffeoylquinic acid in BB. Thus, this study revealed the potential usefulness of both conservation technologies when employed to this type of plants.
In the present study, the antibacterial properties of methanolic extracts prepared from Boletus e... more In the present study, the antibacterial properties of methanolic extracts prepared from Boletus edulis Bull. and Hydnum repandum L. Fr., previously submitted to gamma irradiation, were assessed against clinical isolates with different resistance profiles (two Gram negative bacteria: Escherichia coli and Proteus mirabilis, isolated from urine, and two Gram positive bacteria: MSSAmethicillin-sensitive Staphylococcus aureus, isolated from wound exudate and MRSA-methicillin-resistant Staphylococcus aureus, isolated from expectoration) from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal. The fruiting bodies were collected in Trás-os-Montes (Northeast of Portugal) in November 2012. Gamma irradiation was performed in experimental equipment with four 60 Co sources at 1 and 2 kGy doses Methodology *
A diet rich in natural antioxidant compounds has been linked to a reduced risk of developing chro... more A diet rich in natural antioxidant compounds has been linked to a reduced risk of developing chronic oxidative stress-related diseases, including câncer and cardiovascular and neurodegenerative diseases. In addition to their highly appreciated nutritional value, mushrooms could be an interesting source of antioxidant compounds [l]. Nevertheless, their short shelf-life might be a limitation to the distribution and marketing of fresh mushrooms. Drying is one of the most used conservation methods applied to mushrooms [2], but it causes the reduction ofvegetative cells ofmicroorganisms, which gives rise to a flora of bactéria and füagi that have the ability to survive for long periods in dried foods, producing toxins harmfül to human health [3]. In this sense, electron beam irradiation is a possible way to improve food quality, reduce the incidence of foodbome diseases caused by microorganisms, decontaminate pests, insects or parasites that inflict food spoilage and toxicity, thereby replacing the chemical treatments [3]. Nevertheless, this process should keep the chemical and bioactive characteristics of the matrices. Herein, the effects of electron beam irradiation in the antioxidant potential of Amanita caesarea (Scop. ) Pers. andAmanita curtipes E.-J. Gilbert dried samples were evaluated. The fhiiting bodies were obtained in Trás-os-Montes, in the Northeast of Portugal, in October 2013, and dried at 30 °C in an oven. Subsequently, the samples were divided in four groups with five specimens of each mushroom species: control (non-irradiated, O kGy); sample l (2 kGy); sample 2 (6 kGy) and sample 3 (10 kGy), kept in polyethylene bags. The irradiation was performed at the Institute of Nuclear Chemistry and Technology, in Warsaw, Poland. The antioxidant properties were evaluated through scavenging activity against 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicais, reducing power, inhibition oflipid peroxidation using thiobarbituric acid reactive substances (TBARS) and p-carotenelinoleate model systems. With no exception, irradiated samples (especially for the higher doses) showed to be more antioxidant, either as DPPH radical scavengers, ferric reducers and p-carotene bleaching or TBARS fonnation inhibitors. The higher antioxidant activity was coherent with the leveis of phenolics, which also increased with extending irradiation doses. Except for TBARS formation inhibition, A. caesarea showed higher antioxidant activity than A. curtipes, and besides this action, the assayed mushroom proved to be particularly active as reducing agent. An increased bioactivity with the doses reflects an additional advantage of irradiating mushrooms. Electron beam irradiation might provide a useful altemative to ensure the quality and extend the life ofmushrooms
The effects of gamma irradiation on Lactarius deliciosus (L. ex Fr.) S. F. Gray sugars were evalu... more The effects of gamma irradiation on Lactarius deliciosus (L. ex Fr.) S. F. Gray sugars were evaluated in samples submitted to different storage periods (0, 4 and 8 days) at 4 °C. The irradiations were performed in a 60 Co experimental equipment. Changes in sugars were determined by analyzing the results obtained by high performance liquid chromatography coupled to refraction index detection (HPLC-Rl) through a 2-way analysis of variance and a linear discriminant analysis. Mannitol was by far the most abundant sugar in the analyzed samples. Regarding sugars profile, storage time proved to have higher influence than irradiation dose, mainly reflected in the decrease of fructose and mannitol in stored samples.
A amêndoa já foi um dos principais produtos de exportação do setor agrícola em Portugal. Contudo,... more A amêndoa já foi um dos principais produtos de exportação do setor agrícola em Portugal. Contudo, a presença crescente no mercado mundial de amêndoa produzida na Califórnia a preços muito baixos e o despovoamento do meio rural, sobretudo a partir da década de 1970, levaram ao progressivo abandono da cultura. A amendoeira [Prunus dulcis (Mill.) D. A. Webb], contudo, nunca deixou de ser uma espécie emblemática em Portugal. Ainda que com baixo valor económico, continuou a criar paisagens deslumbrantes, com a sua floração precoce, atraindo turistas ao interior, em particular ao Vale do Douro e afluentes, onde sempre foi mantendo algum valor para a economia familiar. Nos últimos anos, contudo, tem havido um renovado interesse na cultura. O aumento do consumo de amêndoa a nível mundial tem criado condições para que os preços se mantenham um pouco mais atrativos que em anos anteriores o que, associado à falência generalizada do setor arvense de sequeiro do interior do país, tem estimulado o aparecimento de novas plantações de amendoal. O fenómeno é sobretudo relevante no Alentejo, associado a novos regadios como o Alqueva, com plantações em regime intensivo, mas também em Trás-os-Montes onde prevalecem os pomares de sequeiro. Nos anos recentes a amendoeira tem sido valorizada pela amêndoa comestível e pontualmente em roteiros turísticos de inverno associados à floração, como se referiu. Contudo, diversos subprodutos da amendoeira podem ser valorizados, sobretudo os que apresentam maior expressão quantitativa como cascarão (2000t ano -1 ), casca rija (9000 t ano -1 ), tegumento (120 t ano -1 ) e lenha de poda (25000 t ano -1 ). Neste trabalho faz-se uma estimativa da quantidade desses materiais que é produzida em Portugal e apresentam-se pistas para valorizações potenciais.
A elevada perecibilidade é uma característica dos cogumelos consumidos em fresco. Assim, torna-se... more A elevada perecibilidade é uma característica dos cogumelos consumidos em fresco. Assim, torna-se necessária a aplicação de tecnologias eficazes de conservação, permitindo a sua preservação e protegendo, simultaneamente, a sua composição química e valor nutricional. A secagem, apesar de ser uma técnica bastante utilizada, permite o desenvolvimento de bactérias e fungos que têm a capacidade de sobreviver por longos períodos de tempo em alimentos secos; provoca ainda a perda de alguns nutrientes e promove reações enzimáticas e não enzimáticas que levam ao escurecimento do alimento e, também, à oxidação de lípidos e vitaminas [1]. A irradiação surge, assim, como uma alternativa de conservação de alimentos, garantindo a sua qualidade e estando a sua utilização regulamentada na U.E. para vários produtos alimentares [2]. Neste trabalho, avaliaram-se os efeitos da irradiação com feixe de eletrões e do tempo de armazenamento nos parâmetros nutricionais e químicos de amostras silvestres de Macrolepiota procera (Scop.) Singer, previamente submetidas a secagem (em estufa a 30 ºC). A irradiação com feixe de eletrões (doses 2, 6 e 10 kGy) foi efetuada no INCT- Instituto Nuclear de Química e Tecnologia, em Varsóvia, na Polónia e as análises foram efetuadas ao longo do período de armazenamento (0, 6 e 12 meses). Todos os resultados foram comparados com amostras controlo (não irradiadas). O valor nutricional determinou-se de acordo com os procedimentos oficias de análise de alimentos, tendo-se obtido também os perfis em ácidos gordos, tocoferóis, mono e oligossacáridos por técnicas cromatográficas [1]. A irradiação evidenciou maior capacidade em manter o perfil nutricional e químico, relativamente ao tempo de armazenamento. Efetivamente, este último teve um efeito maior em todos os parâmetros analisados, com exceção dos ácidos gordos, que sofreram alterações significativas tanto com as doses aplicadas como com o tempo de armazenamento. A irradiação por feixe de eletrões pode ser considerada uma técnica adequada para a conservação e preservação de cogumelos por períodos de longa duração, ao mesmo tempo que atenua as alterações provocadas pelo tratamento de secagem
Antitumor, antimicrobial and antioxidant activities of basil were studied, along with its charact... more Antitumor, antimicrobial and antioxidant activities of basil were studied, along with its characterization in phenolic compounds, organic acids and soluble sugars. The results placed basil as a valuable candidate for functionalization and conservation of food products, maintaining their nutritional properties, while increasing their shelf life and potential health effects. The basil leaves were then incorporated in ''Serra da Estrela Cheese", either in its dehydrated form or as a decoction. The cheeses were then subject to a nutritional evaluation, being characterized for their fatty acids, minerals and CIE color parameters. To assess the combined effects of plant incorporation and storage time, a 2-way ANOVA was used to process the results, further analysed through a linear discriminant analysis. Overall, basil leaves provided antioxidant activity to the cheeses, reduced the moisture, and preserved the unsaturated fatty acids and proteins. Comparing both incorporation types, the decoctions had a higher functionalizing and conservative effect.
The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial ac... more The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial activity of mushroom species (Boletus edulis, Hydnum repandum, Macrolepiota procera and Russula delica) differently processed (fresh, dried, freeze) were evaluated. : Clinical isolates with different resistance profiles from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal, were used as target microorganisms. The mushrooms antimicrobial activity did not suffer significant changes that might compromise applying irradiation as a possible mushroom conservation technology. Conclusions: 2 kGy dose (independently of using gamma-rays or electron-beams) seemed to be the most suitable choice to irradiate mushrooms. This study provides important results in antimicrobial activity of extracts prepared from irradiated mushroom species.
Sterols are important molecules in the unsaponifiable fraction of several matrices. Ergosterol, w... more Sterols are important molecules in the unsaponifiable fraction of several matrices. Ergosterol, which is an important vitamin D 2 precursor, is clearly the main sterol in mushrooms. Herein, an analytical method for ergosterol determination in cultivated and wild mushrooms was developed using high performance liquid chromatography coupled to ultraviolet detection. The chromatographic separation was achieved in a Inertsil 100A ODS-3 reverse phase column using an isocratic elution with acetonitrile:methanol (70:30, v:v) at a flow rate of 1 mL/min. Different extraction methodologies were tested, using n-hexane, methanol:dichloromethane (75:25, v:v) or chloroform:methanol (20:10, v:v). The method was optimized using Fistulina hepatica and proved to be reproductive and accurate. Ergosterol was the most abundant sterol by a greater extent in all mushrooms. In general, the cultivated species showed higher contents, mainly Agaricus bisporus and Lentinus edodes. Among wild species, Boletus edulis was the mushroom with the highest content in ergosterol. Results were expressed in fat content, dry weight and fresh weight bases. The assessment of ergosterol amounts might be very useful due to the bioactive potential that has been attributed to this molecule and its derivatives.
Trends in Food Science and Technology, Apr 1, 2016
Background: The well-known correlation between diet and physiology demonstrates the great possibi... more Background: The well-known correlation between diet and physiology demonstrates the great possibilities of food to maintain or improve our health, increasing the interest in finding new products with positive physiological effects. Nowadays, one of the top research areas in Food Science and Technology is the extraction and characterization of new natural ingredients with biological activity that can be further incorporated into a functional food, contributing to consumer's well-being. Furthermore, there is a high demand for effective encapsulation methodologies to preserve all the characteristics of bioactive compounds until the physiological action site is reached. Scope and approach: In this review, the relevance of developing standard approaches for the extraction of the highly diverse bioactive compounds was described, as it defines the suitability of the following steps of separation, identification and characterization. Special attention was also dedicated to the encapsulation techniques used on hydrophilic and/or lipophilic compounds (e.g., emulsification, coacervation, supercritical fluid, inclusion complexation, emulsification-solvent evaporation and nanoprecipitation). Key findings and conclusions: Some useful conclusions regarding the selection of the best extraction methodology (Soxhlet extraction, ultrasound-assisted extraction, supercritical fluid extraction, accelerated solvent extraction, or shake extraction) were achieved, considering important aspects such as cost, required technical skills, extract integrity, green chemistry principles, solvent type, sample size, pH, temperature and pressure. In addition, this comprehensive review allowed defining the best protective approach to solve the limitations related to the extremely low absorption and bioavailability of bioactive phytochemicals, overcoming problems related to their low solubility, poor stability, low permeability and metabolic processes in the GI tract.
Agradecimentos: Ministerio da Agricultura (PRODER/FEADER/UE, projecto AROMAP), pelo suporte finan... more Agradecimentos: Ministerio da Agricultura (PRODER/FEADER/UE, projecto AROMAP), pelo suporte financeiro do trabalho e E. Pereira; Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) pelo suporte financeiro ao CIMO (PEst-OE/AGR/UI0690/2014) e L. Barros (SFRH/BPD/107855/2015); Prof. A. Chmielewski, director do INCT, Polonia, e Dr. A. Rafalski pelas irradiacoes com feixe de electroes
Ministerio da Agricultura, Portugal (Projeto PRODER/FEADER/EU no. 53514), pelo financiamento do t... more Ministerio da Agricultura, Portugal (Projeto PRODER/FEADER/EU no. 53514), pelo financiamento do trabalho e pela bolsa atribuida a E. Pereira; a Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), pelo financiamento do CIMO (PEst-OE/AGR/UI0690/2014) e CTN (RECI/AAG-TEC/0400/2012) e pelas bolsas de pos-doutoramento de L. Barros (BPD/107855/2015) e J.C.M. Barreira (BPD/72802/2010). Ao Prof A. Chmielewski, Diretor do INCT, e ao Dr. A. Rafalski, pelo trabalho de irradiacao por feixe de eletroes.
Tree nuts have long been recognized as sources of nutrients in healthy diets, such as the Mediter... more Tree nuts have long been recognized as sources of nutrients in healthy diets, such as the Mediterranean one, besides being increasingly promoted as healthy ingredients for different food applications. In this chapter, recent literature on compositional features of almond, chestnut, hazelnut, and walnut will be comprehensively reviewed. We provide information regarding the profiles of the most relevant macronutrients and micronutrients, discussing the potential nutritional and health effects of these nuts and also focusing on the laboratory methodologies employed. An overview of major compounds in each species is provided throughout the text, covering nuts grown in various regions. This chapter is mainly focused on the edible parts of the selected nuts, so the presented results relate exclusively to the kernels, not other botanical parts, such as leaves, flowers or husks.info:eu-repo/semantics/publishedVersio
Vitamins and mineral elements are among the most important phytochemicals due to their important ... more Vitamins and mineral elements are among the most important phytochemicals due to their important role in the maintenance of human health. Despite these components had already been studied in different plant species, their full characterization in several wild species is still scarce. In addition, the knowledge regarding the in vivo effects of phytochemicals, particularly their bioaccessibility, is still scarce. Accordingly, a membrane dialysis process was used to simulate gastrointestinal conditions in order to assess the potential bioaccessibility of mineral elements in different preparations of Achillea millefolium (yarrow), Laurus nobilis (laurel) and Taraxacum sect. Ruderalia (dandelion). The retention/passage dynamics was evaluated using a cellulose membrane with 34 mm pore. Dandelion showed the highest levels of all studied mineral elements (except zinc) independently of the used formulations (dried plant or infusion), but yarrow was the only species yielding minerals after the dialysis step, either in dried form, or as infusion. In fact, the ability of each evaluated element to cross the dialysis membrane showed significant differences, being also highly dependent on the plant species. Regarding the potential use of these plants as complementary vitamin B 9 sources, the detected values were much lower in the infusions, most likely due to the thermolability effect.
The food industry is always seeking innovative approaches to maintain consumers' interest and inc... more The food industry is always seeking innovative approaches to maintain consumers' interest and increase their awareness towards the healthiness of diets. Therefore, much interest has been given to natural food additives, namely colourants. In this work, a bilberry extract was primarily characterized in terms of anthocyanin compounds by UPLC-DAD-ESI/MSn, and its colouring capacity was further compared with a synthetic anthocyanin colourant (E163) in different yogurt formulations. The prepared samples were evaluated in different periods (0 and 7 days) for nutritional profile, individual fatty acids, soluble sugars and external colour to determine the effects of each additive. Overall, the major anthocyanin compounds in bilberry were malvidin glycoside and delphinidin glycoside derivatives. With regard to the prepared yogurts, all samples maintained the nutritional profile, individual fatty acids and soluble sugars, independent of storage time. Nonetheless, bilberry extracts showed lower colouring capacity when compared to that of E163, despite the higher stability of bilberry extract throughout the storage time, when compared to that of E163. Furthermore, another advantage of this natural extract is that it has potential bioactive properties that can be conferred to foods, due to their high content of bioactive compounds, such as anthocyanins.
The effects of gamma irradiation on Aloysia citrodora, Melissa officinalis, Melittis melissophyll... more The effects of gamma irradiation on Aloysia citrodora, Melissa officinalis, Melittis melissophyllum and Mentha piperita were previously evaluated. Herein, the same species were treated with electron-beam irradiation (EB) and the same parameters were evaluated. Instead of presenting absolute values for each studied parameter, data were evaluated as percentage of induced variation. Besides the newly obtained results, data from a previous work was recalled and normalized in the same manner. Several examples of percentage variations specific to a plant species or irradiation condition were found. Nevertheless, it was not possible to identify unequivocal trends. Even so, when evaluated in an integrative way, the parameters with highest discriminating ability among irradiation conditions or plant species were fatty acids and bioactive indicators. Comparing the effects of gamma and EB irradiations, it might be concluded that the most suitable solution to irradiate aromatic plants would be EB, independently of the used dose.
Innovative Food Science and Emerging Technologies, Aug 1, 2016
Wild plants are widely recognized as high-potential sources of several bioactive compounds. Never... more Wild plants are widely recognized as high-potential sources of several bioactive compounds. Nevertheless, these natural matrices require effective decontamination steps before they might be considered for different industrial purposes. Irradiation techniques are being progressively acknowledged as feasible conservation methodologies, either for their high decontamination effectiveness, as well as for their innocuousness on most chemical and bioactive parameters of the material to be treated. Arenaria montana L. (Caryophyllaceae) is recognized for its phytochemical richness, having a relevant geographical distribution in the Southern Europe. Herein the effects of irradiation (gamma and electron beam up to 10 kGy) were evaluated by comparing the nutritional, chemical and antioxidant profiles in A. montana extracts. In general, the assayed parameters showed statistically significant variations in response to irradiation treatment. Furthermore, the performed LDA allowed identifying the antioxidant indicators as the most affected parameters in irradiated samples, especially when using the 10 kGy dose and e-beam irradiation.
Owing to the overall increase in herbal infusions' consumption, there's a progressively higher ne... more Owing to the overall increase in herbal infusions' consumption, there's a progressively higher need of suitable plant material, as well as adequate conservation techniques to maintain its quality. Among, the available technologies, irradiation is gaining interest as a feasible preservation method. In line with this approach, this wok was designed to evaluate the effects of electron-beam and gamma irradiation over the phenolic profiles of two plant species Melissa officinalis L. (LB) and Melittis melissophyllum L. (BB). Individual phenolics were characterized by high-performance liquid chromatography coupled to a diode array detector and a mass spectrometer (HPLC-DAD-ESI/MS). Irradiated samples showed a general increase in individual phenolic contents, especially in lithospermic acid A in LB and 5-O-caffeoylquinic acid in BB. Thus, this study revealed the potential usefulness of both conservation technologies when employed to this type of plants.
In the present study, the antibacterial properties of methanolic extracts prepared from Boletus e... more In the present study, the antibacterial properties of methanolic extracts prepared from Boletus edulis Bull. and Hydnum repandum L. Fr., previously submitted to gamma irradiation, were assessed against clinical isolates with different resistance profiles (two Gram negative bacteria: Escherichia coli and Proteus mirabilis, isolated from urine, and two Gram positive bacteria: MSSAmethicillin-sensitive Staphylococcus aureus, isolated from wound exudate and MRSA-methicillin-resistant Staphylococcus aureus, isolated from expectoration) from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal. The fruiting bodies were collected in Trás-os-Montes (Northeast of Portugal) in November 2012. Gamma irradiation was performed in experimental equipment with four 60 Co sources at 1 and 2 kGy doses Methodology *
A diet rich in natural antioxidant compounds has been linked to a reduced risk of developing chro... more A diet rich in natural antioxidant compounds has been linked to a reduced risk of developing chronic oxidative stress-related diseases, including câncer and cardiovascular and neurodegenerative diseases. In addition to their highly appreciated nutritional value, mushrooms could be an interesting source of antioxidant compounds [l]. Nevertheless, their short shelf-life might be a limitation to the distribution and marketing of fresh mushrooms. Drying is one of the most used conservation methods applied to mushrooms [2], but it causes the reduction ofvegetative cells ofmicroorganisms, which gives rise to a flora of bactéria and füagi that have the ability to survive for long periods in dried foods, producing toxins harmfül to human health [3]. In this sense, electron beam irradiation is a possible way to improve food quality, reduce the incidence of foodbome diseases caused by microorganisms, decontaminate pests, insects or parasites that inflict food spoilage and toxicity, thereby replacing the chemical treatments [3]. Nevertheless, this process should keep the chemical and bioactive characteristics of the matrices. Herein, the effects of electron beam irradiation in the antioxidant potential of Amanita caesarea (Scop. ) Pers. andAmanita curtipes E.-J. Gilbert dried samples were evaluated. The fhiiting bodies were obtained in Trás-os-Montes, in the Northeast of Portugal, in October 2013, and dried at 30 °C in an oven. Subsequently, the samples were divided in four groups with five specimens of each mushroom species: control (non-irradiated, O kGy); sample l (2 kGy); sample 2 (6 kGy) and sample 3 (10 kGy), kept in polyethylene bags. The irradiation was performed at the Institute of Nuclear Chemistry and Technology, in Warsaw, Poland. The antioxidant properties were evaluated through scavenging activity against 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicais, reducing power, inhibition oflipid peroxidation using thiobarbituric acid reactive substances (TBARS) and p-carotenelinoleate model systems. With no exception, irradiated samples (especially for the higher doses) showed to be more antioxidant, either as DPPH radical scavengers, ferric reducers and p-carotene bleaching or TBARS fonnation inhibitors. The higher antioxidant activity was coherent with the leveis of phenolics, which also increased with extending irradiation doses. Except for TBARS formation inhibition, A. caesarea showed higher antioxidant activity than A. curtipes, and besides this action, the assayed mushroom proved to be particularly active as reducing agent. An increased bioactivity with the doses reflects an additional advantage of irradiating mushrooms. Electron beam irradiation might provide a useful altemative to ensure the quality and extend the life ofmushrooms
The effects of gamma irradiation on Lactarius deliciosus (L. ex Fr.) S. F. Gray sugars were evalu... more The effects of gamma irradiation on Lactarius deliciosus (L. ex Fr.) S. F. Gray sugars were evaluated in samples submitted to different storage periods (0, 4 and 8 days) at 4 °C. The irradiations were performed in a 60 Co experimental equipment. Changes in sugars were determined by analyzing the results obtained by high performance liquid chromatography coupled to refraction index detection (HPLC-Rl) through a 2-way analysis of variance and a linear discriminant analysis. Mannitol was by far the most abundant sugar in the analyzed samples. Regarding sugars profile, storage time proved to have higher influence than irradiation dose, mainly reflected in the decrease of fructose and mannitol in stored samples.
A amêndoa já foi um dos principais produtos de exportação do setor agrícola em Portugal. Contudo,... more A amêndoa já foi um dos principais produtos de exportação do setor agrícola em Portugal. Contudo, a presença crescente no mercado mundial de amêndoa produzida na Califórnia a preços muito baixos e o despovoamento do meio rural, sobretudo a partir da década de 1970, levaram ao progressivo abandono da cultura. A amendoeira [Prunus dulcis (Mill.) D. A. Webb], contudo, nunca deixou de ser uma espécie emblemática em Portugal. Ainda que com baixo valor económico, continuou a criar paisagens deslumbrantes, com a sua floração precoce, atraindo turistas ao interior, em particular ao Vale do Douro e afluentes, onde sempre foi mantendo algum valor para a economia familiar. Nos últimos anos, contudo, tem havido um renovado interesse na cultura. O aumento do consumo de amêndoa a nível mundial tem criado condições para que os preços se mantenham um pouco mais atrativos que em anos anteriores o que, associado à falência generalizada do setor arvense de sequeiro do interior do país, tem estimulado o aparecimento de novas plantações de amendoal. O fenómeno é sobretudo relevante no Alentejo, associado a novos regadios como o Alqueva, com plantações em regime intensivo, mas também em Trás-os-Montes onde prevalecem os pomares de sequeiro. Nos anos recentes a amendoeira tem sido valorizada pela amêndoa comestível e pontualmente em roteiros turísticos de inverno associados à floração, como se referiu. Contudo, diversos subprodutos da amendoeira podem ser valorizados, sobretudo os que apresentam maior expressão quantitativa como cascarão (2000t ano -1 ), casca rija (9000 t ano -1 ), tegumento (120 t ano -1 ) e lenha de poda (25000 t ano -1 ). Neste trabalho faz-se uma estimativa da quantidade desses materiais que é produzida em Portugal e apresentam-se pistas para valorizações potenciais.
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