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- Chemical characterization and antioxidant capacity evaluation of blueberries and currants subjected to different types of productionPublication . Palmeira, Luís; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianIn recent years, with the increasing consumers‘ awareness regarding the beneficial properties of antioxidant fruits for health, small red fruits have been extensively produced. This tendency as led to the search of new and more sustainable ways of organic and integrated production, replacing conventional agriculture, to improve the quality of the fruits, and therefore meet consumers‘ expectations [1–3]. The main interest of this study was the chemical characterization (fatty acids (GC-FID), free sugars (HPLC-RI), organic acids (UFLC-PDA), tocopherols (HPLC-fluorescence), and phenolic compounds (HPLC-DAD/ESI-MS)), and antioxidant properties assessment (TBARS and OxHLIA assays) of blueberry and currant fruits subjected to different types of production (conventional and applying a biological fertilizer, Ecoser), providing information that allows a comparison and a more conscious choice of the most suitable production type. The results showed that the chemical composition of blueberry and currant fruits is influenced by the production methodology. Blueberries fertilized with Ecoser revealed higher concentrations of γ- and δ-tocopherol, monounsaturated and polyunsaturated fatty acids, oxalic acid, quinic acid, and malic acid, while blueberries grown in the traditional way showed high levels of glucose and fructose, as well as saturated fatty acids, quinic acid, and phenolic compounds. Regarding currants, those grown organically showed high concentrations of lipids, fructose, glucose, ascorbic acid, saturated and monounsaturated fatty acids, phenolic acids, and flavonoids, whereas currants grown in conventional agriculture showed high levels of sucrose, polyunsaturated fatty acids, and anthocyanins. On the other hand, in the antioxidant activity assessment, a better inhibition of lipid peroxidation was evidenced by the currants produced in biological mode and in the blueberries produced in a conventional way. In terms of the inhibition of oxidative hemolysis, the best results were achieved by the currants and blueberries cultivated in biological mode. This study can serve as a basis to determine the most suitable production parameters, depending on the intended application of the fruits in industry, or the consumers‘ preferences.
- Valorização de recursos endógenos em Tierras de Miranda de l Burro i l GueiteiroPublication . Palmeira, Luís; Santos, Briolanja; Possamai, Fernanda; Cruz, Luís Royer Oliveira; Rodrigues, Joana Almeida; Novais, Cláudia; Sousa, Maria João; Pereira, Olívia R.; Cabo, Paula; Pires, LuísaO Planalto Mirandês é uma região com forte identidade cultural, incluindo a Raça Asinina de Miranda, em risco de extinção. Um projeto de cocriação no âmbito do EMER-N desenvolveu soluções para a criação de valor na atividade turística, incluindo o desenvolvimento de três sais de banho enriquecidos com leite de burra, com benefícios anti-envelhecimento e propriedades antioxidantes. Esses sais de banho aromatizados, juntamente com o ambiente relaxante da região, oferecem uma experiência turística autêntica e diferenciada, transformando o tratamento em um verdadeiro tratamento Spa para a mente e corpo.
- Influência do sistema de produção e fertilização nas propriedades nutricionais, químicas e bioativas de frutos vermelhos produzidos no Norte de PortugalPublication . Palmeira, Luís; Pereira, Carla; Barros, LillianOs pequenos frutos vermelhos, como os mirtilos (Vaccinium corymbosum L.) e as groselhas (Ribes rubrum L.), são culturas consideradas emergentes em Portugal, com um elevado potencial de crescimento. Apesar de o consumo destes frutos em Portugal ser ainda pouco expressivo, tem vindo a verificar-se um aumento razoável, comparativamente com o século passado, com o crescente interesse dos consumidores por alimentos funcionais e com potencial nutracêutico. Por outro lado, em 2016, os pequenos frutos vermelhos renderam nas exportações mais de 100 milhões de euros, sendo uma aposta bastante considerada e inclusive uma alternativa de investimento por muitos empresários portugueses. Dadas as condições edafoclimáticas do nosso país e a possibilidade de produção de diferentes cultivares em épocas de menor oferta nos principais nichos de mercado, estes frutos constituem uma oportunidade de negócio interessante. Neste sentido, a preocupação pela produção em formas mais sustentáveis como a produção biológica e integrada, em substituição de uma produção que visa apenas a ótica produtiva, potencia a obtenção de frutos de qualidade, ricos em compostos antioxidantes de valor acrescentado, permitindo corresponder às expetativas dos consumidores mais exigentes. Este estudo teve como objetivo analisar e comparar a composição química e as propriedades antioxidantes de mirtilos e groselhas sujeitos a diferentes tipos de produção, fornecendo informação que permita uma escolha mais consciente. O modo de produção revelou influenciar não só os parâmetros nutricionais, como também a composição em açucares livres, ácidos gordos, tocoferóis, ácidos orgânicos e compostos fenólicos. Assim, os mirtilos cultivados em modo convencional revelaram teores superiores de hidratos de carbono e energia, frutose e glucose, ácidos gordos saturados, ácido quínico e compostos fenólicos. Por sua vez, os mirtilos fertilizados com Ecoser revelaram concentrações mais elevadas de γ- e δ-tocoferol, ácido gordos monoinsaturados e polinsaturados, ácido oxálico, ácido quínico e ácido málico. No que respeita às groselhas, verificaram-se teores mais elevados de hidratos de carbono e energia, sacarose, ácidos gordos polinsaturados e antocianinas nos frutos cultivados em agricultura convencional. Por outro lado, as groselhas cultivadas em modo biológico revelaram concentrações mais elevadas de lípidos, frutose e glucose, ácido ascórbico, ácidos gordos saturados e monoinsaturados, ácidos fenólicos e flavonóides. Estas variações refletiram-se também na bioatividade destes frutos em termos de inibição da peroxidação lipídica, potenciada nas groselhas produzidas em modo biológico e nos mirtilos produzidos de forma convencional, e da inibição da hemólise oxidativa, também melhorada nas groselhas cultivados em modo biológico e nos mirtilos fertilizados com Ecoser. Os resultados obtidos no presente estudo poderão servir de base para a definição de parâmetros de produção que melhor se ajustem à cultura de cada fruto.
- Chemical features of green fig pulp and peel: phenolic, organic acids, and tocopherols profilePublication . Palmeira, Luís; Pereira, Carla; Dias, Maria Inês; Barros, Lillian; Ferreira, Isabel C.F.R.Ficus carica L. is one of the first domesticated trees of the Neolithic Revolution; it is native to western Asia and was later spread to the Mediterranean region. Its fruits, figs, are widely consumed in fresh or dried form, or used for spirit beverage and jam due to their sweet taste and well-known nutritional properties [1, 2]. Nevertheless, the fruit peel is often discarded in the preparation of food products that only require the pulp, and this part of the fruit is reported as a good source of phenolic compounds with several beneficial properties for human health [3], thus the importance of studying the different parts separately is justified. Therefore, the aim of this study was to explore and compare the chemical composition of green fig pulp and peel. For that purpose, the phenolic composition was assessed by HPLC-DAD-ESI/MS, organic acids by HPLC-PDA, and tocopherols by HPLC-fluorescence. Regarding phenolic compounds, the highest concentration was found in the peel, which revealed the presence of flavonoids and phenolic acids in similar concentrations, with quercetin-3-O-rutinoside, 5-O-caffeoylquinic acid, and vanilic acid malonyl-di-deoxyhexoside as the major compounds detected. On the other hand, the pulp presented a prevalence of phenolic acids, among which caffeic acid hexoside was the most abundant one. In terms of organic acids, despite the higher amounts of oxalic and succinic acids found in the pulp, the peel showed higher concentrations of quinic, malic, citric, and total organic acids. The tocopherols profile was similar for both samples, with the four isoforms being detected; α-, β-, and total tocopherols were mostly found in the peels, whereas γ- and δ-tocopherol were prevalent in the pulp. The results presented highlight the importance of this fruit in human diet, given its richness in nutritional and bioactive compounds that contribute for a balanced and functional diet. Additionally, the chemical composition of fig peel justifies the recovery of this part of the fruit for further application in food industry, in the cases where it is discarded for the preparation of fig-based products.
- Nutritional, chemical and bioactive profiles of different parts of a Portuguese common fig (Ficus carica L.) varietyPublication . Palmeira, Luís; Pereira, Carla; Dias, Maria Inês; Abreu, Rui M.V.; Corrêa, Rúbia C.G.; Pires, Tânia C.S.; Alves, Maria José; Barros, Lillian; Ferreira, Isabel C.F.R.This study aims to give an unprecedented contribution on the chemical composition and bioactivities of the most produced and appreciated Portuguese fig variety (“Pingo de Mel”) with the view of expanding the knowledge on its potentialities. An advanced characterization of its peel and pulp parts was carried out. Four free sugars (glucose, fructose, trehalose and sucrose), 5 organic acids (oxalic, quinic, malic, citric, and succinic acids), tocopherols in all their 4 forms, besides 23 fatty acids were detected in the samples. Fifteen different phenolic components were found in the peel hydroethanolic extract; whereas 12 were detected in the pulp hydroethanolic extract. Quercetin-3-O-rutinoside (rutin) was the major constituent of the peel, accounting for 33.8% of its phenolic content, followed by 5-O-caffeoylquinic acid and vanillic acid malonyl di-deoxyhexoside. Caffeic acid derivatives, such as caffeic acid hexosides, were the major components of pulp, followed by vanillic acid derivatives and O-caffeoylquinic acid. Both extracts displayed promising antioxidant capacities in all methods used, namely the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging, the reducing power, the inhibition of β-carotene bleaching assays, the thiobarbituric acid reactive substances assay and the oxidative haemolysis inhibition assay; however, the peel presented significantly lower IC50 values than pulp. The extracts showed practically identical antibacterial capacities, being effective against methicillin-sensitive Staphylococcus aureus (MICs=2.5 mg/mL), besides methicillin-resistant S. aureus, Escherichia coli and Morganella morganii (MICs=5 mg/mL). The obtained results evidence that the fig peel is superior to the corresponding pulp as it relates to nutritional and phenolic profiles as well as bioactivities, endorsing the urgency in valorising and exploiting this usually discarded industrial by-product.
- Effects of the fertilization system on the chemical profile of Ribes rubrum L.Publication . Palmeira, Luís; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianRibes rubrum L. fruits are widely consumed for their pleasant taste and nutritional features (Figure 1). These small red fruits are also considered superfoods, mostly due to their high content of phenolic compounds, fiber, iron, and vitamin C, among others, which confer them anti-inflammatory, antioxidant, antibacterial, depurative, and diuretic properties.1 In fact, in the last years, there has been a reasonable increase of these fruits’ consumption, with the growing interest of consumers in functional foods and the sustainability of their production. In this sense, organic and integrated production has been gaining expression, being seen as a way to enhance the quality of the fruits, rich in added-value antioxidant compounds, allowing to meet the most demanding consumers’ expectations.2 Through this study, fruits produced conventionally and by applying a biological fertilizer were compared in terms of nutritional value (AOAC) and fatty acids (GC-FID), free sugars (HPLC-RI), organic acids (UFLC-PDA), tocopherols (HPLC-fluorescence), and phenolic compounds (HPLC-DAD/ESI-MS) composition. Moreover, the antioxidant properties of their hydroethanolic extracts (ethanol:water 80:20, v/v) were assessed by two cell-based methods (TBARS and OxHLIA). In general, higher levels of carbohydrates and energy, sucrose, polyunsaturated fatty acids and anthocyanins were found in the fruits grown in conventional agriculture. On the other hand, the fruits cultivated in biological mode showed higher concentrations of lipids, fructose and glucose, ascorbic acid, saturated and monounsaturated fatty acids, phenolic acids and flavonoids. This difference in the chemical profile revealed to influence the bioactivity of these fruits, both in terms of inhibition of lipid peroxidation (TBARS) and oxidative hemolysis (OxHLIA), which were enhanced in the fruits produced in biological way. The results obtained in the present study may serve as a basis for the definition of production parameters that best fit the culture of R. rubrum.
- Extraction of Chlorophylls from bioresidues of Daucus Carota L. (Carrots) aerial parts for food colorants developmentPublication . Molina, Adriana K.; Gomes, Leonardo Corrêa; Palmeira, Luís; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianThe use of bio-residues from fruits and vegetables such as seeds, peels, aerial parts, etc., in the food industry has been of great interest due to the possibility of developing new secondary added-value materials such as natural colorants, which not only provide a colour to the food or product, but also provide health benefits to the consumer (Tiwari et al. 2019). In the present study, the extraction of chlorophylls from the aerial parts of carrots was carried out in order to develop natural food colourants. For that purpose, two types of extraction (maceration and ultrasound-assisted extraction) were performed to maximise the yield of chlorophyll recovery. Three types of solvents were used, prioritising green solvents (water, 90% ethanol, and hexane). At the same time, different parameters were varied in each of the techniques: i) in maceration: extraction time and solvent; ii) in ultrasound-assisted extraction: power and solvent. The extractions were carried out protecting the samples from light and the results were obtained using a newly developed chromatographic method through high performance liquid chromatography (HPLC) coupled to a diode array detector (DAD) and mass spectrometry (MS). In general, the aerial parts of carrot revealed as main compounds chlorophylls a and b, as well as derivatives in significant concentrations. The ultrasound technique proved to be more efficient than maceration extraction, with higher extraction yields when higher ultrasonic power was used. Compared to water and hexane, ethanol allowed the extraction of greater amounts of chlorophylls. These compounds can find application in food industry, but also in other industrial fields, given their high coloring properties, making these bioresidues valuable sources to exploit for colorants development.
- Nutritional evaluation and development of Anthocyanin-Rich colouring formulations from bioresidues of Lonicera Caerulea L. fruitsPublication . Molina, Adriana K.; Palmeira, Luís; Pereira, Carla; Dias, Maria Inês; Heleno, Sandrina A.; Barreiro, M.F.; Barreira, João C.M.; Ferreira, Isabel C.F.R.; Barros, LillianThe production of waste in different industries such as food or agro-industry can lead to environmental pollution and economic losses. Therefore, the transformation of these biowaste into other raw materials has become an important part of industrial processes, as they can be used for human or animal consumption, which would lead to environmental and economic benefits in the industries (Kowalska et al. 2017). In this perspective, this study aimed to evaluate the nutritional properties and to characterize in terms of anthocyanin and non-anthocyanin compounds the bio-residues of Lonicera caerulea L. fruits (haskap) (fallen, maggoty and/or bird-bitten fruits, not appropriated for consumption). Moreover, four anthocyanin-based colouring formulations (two liquid and two solid) were developed by means of thermal gelation (with adragant gum and pectin) and spray-drying (with Arabic gum and maltodextrin) methodologies. Preliminary pasteurization studies were carried out to determine the best preservation conditions. The extracts were pasteurized prior to the preparation of the colorants, thus guaranteeing their microbiological safety. The colorants stability was evaluated over three months (stored at 3 °C and room temperature) by monitoring colour variation, anthocyanin concentration, and cytotoxicity. The fruit biowaste presented a balanced nutritional value, showing carbohydrates as the main macronutrients, as well as proving to be excellent sources of anthocyanins, mainly cyanidin derivatives. On the other hand, the solid formulations revealed a higher stability, with lower variations in colour and anthocyanin concentration, especially the formulations containing stabilising agents. None of the colorant formulations (solid or liquid solutions) revealed cytotoxic properties for a non-tumour primary culture of porcine liver cells, thus validating their feasibility for application in the food industry without associated toxicity issues. Thus, the present study allowed obtaining stable anthocyanin-based colouring formulations using Lonicera caerulea L. biowaste, with high potential to be used in several sectors such as food, pharmaceutical, and cosmetics.
- Effects of diferente production systems on red fruits nutritional propertiesPublication . Palmeira, Luís; Molina, Adriana K.; Pereira, Carla; Barros, Lillian; Ferreira, Isabel C.F.R.Red fruits are considered as emerging crops in Portugal, with a high growth potential. Among which, raspberries (Rubus idaeus L.), blueberries (Vaccinium myrtillus L.), and currants (Ribes rubrum L.) have been increasingly cultivated, similarly to strawberries (Fragaria x ananassa Duch.), a widespread culture in Portugal, for being considered valuable sources of phytochemicals with bioactive properties [1,2]. Given this tendency, there is a growing concern for production in more sustainable forms, by reducing the application of chemical fertilizers, replacing the well- known conventional production and boosting the fruits quality. With that in mind, the objective of this study was to analyse and compare the nutritional value and sugars composition of raspberries and blueberries, subjected to conventional production and using a biostimulant (“Ecoser”), and currants and strawberries, obtained by conventional and biological production. The nutritional value was evaluated following official food analysis methods (AOAC) and the free sugars profile was obtained by HPLC-RI [3]. In all the analysed fruits, as expected, carbohydrates were the major macronutrients found. In raspberries and blueberries, the second most abundant macronutrients were proteins, which levels were increased by “Ecoser” fertilization. In raspberries, it also enhanced the production of carbohydrates, leading to a higher energy value. Regarding currants and strawberries, following carbohydrates, proteins were the most abundant macronutrients, which levels decreased in biologically produced strawberries. This production type increased the ash levels in both cultivars and decreased the carbohydrates concentration, which was reflected in a lower caloric value. In terms of free sugars composition, all the analysed red fruits presented fructose, glucose, and sucrose, with the exception of blueberries, where sucrose was not detected. The treatment with “Ecoser” enhanced free sugars production in raspberries, having the opposite effect in blueberries. On the other hand, the biological production allowed increased levels of fructose and glucose, but lower concentrations of sucrose in currants, whereas in strawberries, fructose and glucose were produced in lower quantities and sucrose production was increased. These observations led to conclude that the effect of the production type on sugars composition depends on the cultivated fruit. This study provides valuable information regarding the composition of red fruits subjected to different production systems, allowing producers to adopt the most suitable system for each cultivar.
- Production and fertilization system affects the nutritional, chemical, and bioactive properties of small red fruitsPublication . Palmeira, Luís; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianSmall red fruits such as bkueberries and currants as emerging crops in Portugal, with a high growth potential