Browsing by Author "Baraldi, Ilton J."
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- Anthocyanin-rich extract obtained from Prunus Spinosa L. by ultrasound assisted extraction for coloring purposesPublication . Leichtweis, Maria Gabriela; Pereira, Carla; Prieto Lage, Miguel A.; Alves, Maria José; Calhelha, Ricardo C.; Barreiro, M.F.; Baraldi, Ilton J.; Ferreira, Isabel C.F.R.; Barros, LillianAnthocyanins are a group of natural pigments presenting a range of colours between red, blue, and violet that are characteristic of various fruits and vegetables. A complex profile of anthocyanins, predominantly cyanidin 3-rutinoside and peonidin 3-rutinoside, was previously identified in Prunus spinosa L. fruit, a bitter and astringent fruit from a wild shrub that is poorly commercially exploited [1]. In this sense, the objective of this work was to develop a natural food colourant based on anthocyanins extracted from the epicarp of P. spinosa fruits. For that purpose, a conventional extraction method, maceration, and a rapid and low-cost ultrasound procedure were applied for the extraction of anthocyanins from this matrix. To achieve the conditions that maximize anthocyanins’ extraction, a response surface methodology was applied using a circumscribed central composite design with three variables and five levels, being the variables time, temperature, and ethanol content, in the case of maceration extraction, whereas for ultrasound assisted extraction, temperature was replaced by ultrasound power. The anthocyanins were identified and quantified by HPLC-DAD-ESI/MS. The optimized extract was assessed in terms of antioxidant and antimicrobial capacity, and hepatotoxicity. Ultrasound assisted extraction was the most efficient method, under optimum conditions of 5.00±0.15 min, 400.00±32.00 W and 47.98±2.88% ethanol, where the extraction yield was 68.60±2.06% (v/v), with a total anthocyanin content of 18.17±1.82 mg/g of dry extract and 11.76±0.82 mg/g of dry epicarp. Regarding bioactivity, the optimized extract showed antioxidant and antimicrobial activity and it did not show hepatotoxic effects in a primary culture of porcine liver cells. To validate its coloring properties, the anthocyanin-rich extract was incorporated into a typical Brazilian confectionery product "beijinho", proving its applicability as food colorant.
- Avaliação do teor em compostos fenólicos e atividade antioxidante de folhas de videira com vista ao seu aproveitamento para uso alimentarPublication . Lima, Adriano Freitas; Bento, Albino; Pereira, J.A.; Baraldi, Ilton J.; Malheiro, RicardoA videira (Vitis vinifera L.) é uma das plantas mais cultivadas em Portugal, sendo que as suas folhas não têm praticamente utilização. Trabalhos recentes demonstraram que são constituídas por uma série de componentes que lhe conferem propriedades e funções de elevada importância. No presente trabalho, pretendeu-se avaliar as folhas de diferentes castas de videira no que respeita ao seu teor em antioxidantes e bioatividade com vista à sua inclusão na dieta humana. Foram selecionadas 10 castas de videira, quatro tintas (Tinta Amarela, Tinta Roriz, Touriga Franca e Touriga Nacional) e seis brancas (Côdega do Larinho, Fernão Pires, Gouveio, Malvasia Fina, Rabigato e Viosinho) cultivadas no Planalto Mirandês, e colhidas amostras de folhas sãs. Prepararam-se extratos aquosos onde foi avaliado o teor em compostos fenólicos, derivados do ácido hidroxicinámico e flavonóis e a atividade antioxidante (DPPH, ABTS, poder redutor, e a capacidade redutora total). De uma maneira geral foram registados maiores teores de fitoquímicos e uma maior atividade antioxidante nas castas brancas em relação às castas tintas. A Malvasia Fina foi a casta que apresentou teores mais elevados de compostos e maior atividade antioxidante, enquanto a Touriga Franca foi a que apresentou valores mais reduzidos. O teor em fenóis totais variou entre 114 e 145 mg g-1 de extrato enquanto os teores de derivados do ácido hidroxicinámico e flavonóis variaram entre 38 e 49 mg g-1 e entre 77 e 102 mg g-1 (Gouveio e Malvasia Fina respetivamente). Os valores de EC50 (concentração efetiva que inibe 50% dos radicais livres) variaram entre os 0,133 e 0,234 mg mL-1 para o DPPH (Rabigato e Tinta Roriz respetivamente) e entre os 0,258 e 0,402 mg mL-1 para o ABTS (Malvasia Fina e Touriga Franca). Os resultados obtidos indicam que as castas brancas são mais interessantes no teor em componentes bioativos e potencial antioxidante, sendo as folhas de Malvasia Fina as que apresentaram maior potencialidade para incluir como ingrediente na dieta alimentar.
- Chemical composition and bioactive properties of byproducts from two different kiwi varietiesPublication . Dias, Murilo Esteves; Caleja, Cristina; Pereira, Carla; Calhelha, Ricardo C.; Kostić, Marina; Soković, Marina; Tavares, Débora; Baraldi, Ilton J.; Barros, Lillian; Ferreira, Isabel C.F.R.Kiwis are an example of fruits with excellent bioactive properties worldwide appreciated and consumed generating tons of waste. Thus, the objective of this work was to compare two varieties of kiwi: Actinidia deliciosa cv. “Hayward” (green) and Actinidia spp. (red) regarding the nutritional value of their pulps, chemical composition and bioactivities of each pulp and peel. The results revealed that pulps have a high water content and low amount of other macronutrients. Both parts of red kiwi presented the highest tocopherols content and red kiwi pulp presented the highest content in ascorbic acid. In general, the peels exhibited the highest antioxidant activity and green kiwi peels showed cytotoxicity and anti-inflammatory activity, which could be related to its higher content in phenolic compounds, especially B-type (epi)catechin dimer. Therefore, kiwi components currently underutilized may be indicated as a source of natural functionalizing ingredients with several benefits for human health.
- Cooking impact in color, pigments and volatile composition of grapevine leaves (Vitis vinifera L. var. Malvasia Fina and Touriga Franca)Publication . Lima, Adriano Freitas; Pereira, J.A.; Baraldi, Ilton J.; Malheiro, RicardoGrapevine leaves (Vitis vinifera L. var. Malvasia Fina and Touriga Franca) under culinary treatment (blanching and boiling at 60, 75 and 90 min) were studied for their color, pigments and volatile fraction changes. Blanching and boiling caused a decrease in luminosity and a loss of green coloration in both varieties, while a yellow-brownish color arose. Significant correlations were established between the loss of green color (monochromatic variable a ∗ ) and the total chlorophylls content. The main volatiles in fresh leaves [(Z)-3-hexenal, (Z)-3-hexen-1-ol, and (Z)-3-hexenyl acetate] were drastically reduced by blanching and suppressed by boiling. Other compounds like pentanal and 6-methyl-5-hepten-2 one arose from blanching and boiling. A boiling time of 60 min is adequate for the culinary process of grapevine leaves, since the product is considered edible and the pigments and volatile changes are not as drastic as observed at 75 and 90 min of boiling.
- Determinação de antocianinas no epicarpo de frutos de Prunus spinosa L.Publication . Leichtweis, Maria Gabriela; Pereira, Carla; Backes, Emanueli; Carvalho, Ana Maria; Baraldi, Ilton J.; Barros, Lillian; Ferreira, Isabel C.F.R.A fim de otimizar processos e/ou desenvolver novos produtos, a indústria alimentar tem utilizado diversas substâncias, denominadas aditivos alimentares [1]. Estes aditivos são adicionados aos alimentos de forma a terem uma contribuição tecnológica e/ou fisiológica, no entanto, existe também uma preocupação por parte dos consumidores relativa aos efeitos adversos que alguns dos aditivos artificiais podem ter. Os corantes são uma das classes de aditivos, amplamente utilizados para conferir coloração aos alimentos. Atualmente, existe uma grande tendência de substituição de corantes artificiais por alternativas naturais. As antocianinas são um grupo de pigmentos que apresentam uma coloração vermelha, azul e/ou violeta, estando presentes em muitas flores e frutos, podendo ser consideradas alternativas aos corantes artificiais [2]. Os frutos de Prunus spinosa L. (abrunho) apresentam um epicarpo de coloração azul intensa evidenciando ser uma fonte promissora de corantes naturais. Neste trabalho, efetuou-se a caracterização do epicarpo do abrunho em termos de antocianinas, determinadas por cromatografia líquida de alta eficiência acoplada a um detetor de díodos e a um espetrómetro de massa (HPLC-DAD-ESI/MS). A identificação dos compostos foi realizada utilizando padrões, quando disponíveis, comparando os seus tempos de retenção, espetros UV-Vis e espetros de massa. Na ausência de padrões, a identificação foi efetuada pelo perfil de fragmentação e por comparação com a informação disponível na literatura. A quantificação foi realizada a partir das áreas dos picos registados ao comprimento de onda de 520 nm, por comparação com as curvas de calibração dos padrões. O epicarpo do abrunho apresentou dois compostos antociânicos, cianidina-3-rutinósido ([M-H]- a m/z 595) e peonidina-3-rutinósido ([M-H]- a m/z 609), estando a primeira molécula em maior concentração. Esta matriz poderá ser considerada uma fonte de pigmentos na gama de cores vermelho-roxo, tendo aplicabilidade tanto na indústria alimentar como farmacêutica.
- Development of a natural anthocyanin-based food colorant obtained from the fruit epicarp of Prunus spinosa L.Publication . Leichtweis, Maria Gabriela; Pereira, Carla; Prieto Lage, Miguel A.; Barreiro, M.F.; Baraldi, Ilton J.; Barros, Lillian; Ferreira, Isabel C.F.R.Prunus spinosa L. is a wild shrub with bitter and astringent fruits with poor commercial value. Nevertheless, they are rich sources of anthocyanins, more specifically cyanidin 3-rutinoside and peonidin 3-rutinoside, which are concentrated in the epicarp. These compounds possess recognized colouring properties and have been increasingly explored for substitution of artificial colorants, for being safer alternatives. In this context, the present work aimed to develop an anthocyanin-based food colorant obtained from P. spinosa fruit epicarp. The conditions that maximize the extraction were optimized, comparing heat (HAE) and ultrasound (UAE) assisted extraction techniques. For that purpose, a response surface methodology was applied, using a circumscribed central composite design with three variables and five levels, being the relevant variables time, temperature (HAE) or power (UAE), and ethanol concentration. The anthocyanin compounds were quantified by HPLC-DAD-ESI/MS. Furthermore, the bioactivity of the optimal extract was assessed through antioxidant, antimicrobial, and cytotoxic activity assays. UAE was the most efficient method, under optimal conditions of 5.0 ± 0.2 min, 400 ± 32 W, and 48 ± 3% ethanol, where the extraction yield was 68.60 ± 2.1%, with a total anthocyanin content of 18 ± 2 mg/g (dried extracted residue-basis) and 11,8 ± 0,8 mg/g (dried epicarp-basis). Additionally, these response values were slightly improved when the solid-to-liquid ratio effect at the optimal conditions in a dose-response format was tested, showing a steady decreasing pattern in the range of 5 to 250 g/L. Regarding bioactive properties, the obtained extract presented antioxidant activity, with EC50 values of 204.22 ± 0.02 μg/mL for the TBARS assay and 296 ± 4 and 509 ± 3 μg/mL for OxHLIA method at 60 and 120 min of reaction, respectively; and antimicrobial properties, allowing the growth inhibition of 9 bacteria strains of public health interest in concentrations from 2.5 to 20 mg/mL. Besides, the obtained extract did not show hepatotoxic effects on a porcine liver primary cell culture (PLP2), being thus safe for incorporation into foodstuff. Lastly, the anthocyanin-based extract was introduced in a traditional Brazilian confectionary product, “beijinho”, where its colouring capacity was confirmed.
- Development of a natural ingredient from kiwi epicarp with potential application in the food industryPublication . Caleja, Cristina; Dias, Maria Inês; Pereira, Carla; Calhelha, Ricardo C.; Kostić, Marina; Soković, Marina; Tavares, Débora; Baraldi, Ilton J.; Barros, Lillian; Ferreira, Isabel C.F.R.Kiwifruit is a recognized source of bioactive compounds with beneficial properties for consumers’ health [1]. Although only pulp is normally consumed, there are several studies in literature that have been exploring the fruits epicarp, which is characterized as an excellent source of bioactive compounds. Thus, since the food industry produces annually tons of this normally discarded and unused residue [2], this work aimed to characterize two varieties of kiwi (Actinidia delicious cv. "Hayward" - green pulp kiwi variety and Actinidia spp. - red pulp kiwi variety), comparing the two pulps and epicarps. This study will valorize these bio-residues. The proximal composition (protein, fat, carbohydrates and ash contents, and energy) of the pulp of these varieties, as well as the composition in free sugars, fatty acids, organic acids and tocopherols, and the study of the bioactivities (antioxidant, anti-inflammatory, cytotoxic and antimicrobial activities) of the pulp and epicarp were evaluated. A hydroethanolic extraction was used to obtain compounds subsequently identified and quantified by HPLC-DAD-ESI/MS. The results revealed that pulps have a high water content and low amount of other macronutrients. Both epicarp varieties presented a higher concentration of phenolic compounds than the corresponding pulp. Additionally, only Actinidia spp. (red pulp kiwi variety) presented an anthocyanin, cyanidin-O-pentosylhexoside. α-tocopherol was the most abundant vitamer in all the analyzed parts. Four organic acids (quinic, malic, citric and ascorbic acids) were identified in all the studied samples. The best antioxidant activity was shown by the epicarps, highlighting the green pulp kiwi as the best variety. Similarly, only the epicarp of the green pulpkiwi variety presented positive results for all the tested cell lines, being able to inhibit the cell growth in a moderate way. Additionally, none of the extracts showed toxicity in a porcine liver cell line at the highest tested concentration (GI50> 400 μg/mL). Both kiwi varieties also demonstrated an excellent antimicrobial activity against some pathogenic bacteria. These results confirm the potential application of kiwi epicarp in the food industry as a source of functional compounds with bioactive properties, contributing in the valorization of these bio-residues.
- Efeito do processamento alimentar na cor, composição volátil e bioatividade de folhas de videira da casta Malvasia FinaPublication . Lima, Adriano Freitas; Bento, Albino; Baraldi, Ilton J.; Pereira, J.A.; Malheiro, RicardoEstudos preliminares demonstraram, que as folhas de videira de castas brancas têm um potencial antioxidante e uma composição superior em compostos bioativos comparativamente a castas tintas, sendo uma mais-valia quando inseridas na dieta alimentar. Deste modo, estudou-se o efeito do processamento alimentar em folhas de videira da casta Malvasia Fina. Foi avaliada a cor, composição volátil, pigmentos (clorofilas e carotenoides), atividade antioxidante e compostos bioativos (compostos fenólicos, derivados do ácido hidroxicinámico e flavonóis) presentes em folhas frescas, branqueadas, e cozidas sobre pressão durante 60, 75 e 90 minutos (t60 min, t75 min e t90 min). O processamento provocou alteração na cor (a* = -14.6 e 2.39 em folhas frescas e t90 min respetivamente), sobretudo devido à perda de clorofilas (528 e 124 mg kg-1 em folhas frescas e t90 min respetivamente) enquanto a redução em carotenoides foi menos evidente (381 e 327 mg kg-1 em folhas frescas e t90 min respetivamente). O principal composto volátil presente em folhas frescas foi (Z)-3-hexen-1-ol acetato (associado a odores verdes e herbáceos) com 6,74 mg kg-1, reduzindo-se o seu teor com o branqueamento, para 0,23 mg kg-1, e desaparecendo nas folhas processadas. Por outro lado a cetona 6-metil-5-hepten-2-ona (associada ao odor de cozido) apresentou os seguintes teores: 0,03; 1,26; 0,35; 0,13; e 0,19 mg kg-1 (folhas frescas, branqueadas, t60 min, t75 min e t90 min, respetivamente). Verificou-se uma perda drástica na atividade antioxidante com o processamento, devida à perda de compostos antioxidantes, principalmente fenóis (169 e 130 mg kg-1 entre folhas frescas e t90 min) e flavonóis (104 e 70 mg kg-1 entre folhas frescas e t90 min). Neste trabalho conclui-se que as folhas da casta Malvasia Fina têm um grande potencial para serem exploradas para consumo humano, contudo, para que possam manter as suas propriedades bioativas, é desaconselhado o seu processamento por longos períodos.
- Effect of ultrasound on the rheological and mcrobiological properties of the olive pastePublication . Teixeira, Hugo Rafael Duarte; Steinmacher, Nádia Cristiane; Feltrin, Valdemar P.; Peres, António M.; Baraldi, Ilton J.The olive tree (Olea europaea L.) Is one of the most important cultures of the Mediterranean landscape. Olive oil and fermented table olives (Fig. 1) are (he most important products from olive, however in an attempt to take advantage of raw material that visually is not within the standards of quality, emerged the olive paste (Fig. 2), which is basically pitted table olives, mixed with olive oil, lemon juice and spices. Ultrasound is a technology that has proven quite effective in pasteurization process, extracting, homogenizing, among others. It is an Interesting technology due to is considered clean, has low maintenance and operational costs and enable satisfactory results as an adjunct for manufacturing a wide range of products. The aim of this work was to study the effect of ultrasound on rheological and microbiological properties of the olive paste and compare results with olive paste made through mechanical homogenization and thermal pasteurization.
- Effect of ultrasound on the rheological and mcrobiological properties of the olive pastePublication . Teixeira, Hugo Rafael Duarte; Steinmacher, Nádia Cristiane; Feltrin, Valdemar P.; Peres, António M.; Baraldi, Ilton J.The olive tree (Olea europaea L.) Is one of the most important cultures of the Mediterranean landscape. Olive oil and fermented table olives (Fig. 1) are (he most important products from olive, however in an attempt to take advantage of raw material that visually is not within the standards of quality, emerged the olive paste (Fig. 2), which is basically pitted table olives, mixed with olive oil, lemon juice and spices. Ultrasound is a technology that has proven quite effective in pasteurization process, extracting, homogenizing, among others. It is an Interesting technology due to is considered clean, has low maintenance and operational costs and enable satisfactory results as an adjunct for manufacturing a wide range of products. The aim of this work was to study the effect of ultrasound on rheological and microbiological properties of the olive paste and compare results with olive paste made through mechanical homogenization and thermal pasteurization.