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Com a viragem do século, as doenças cardiovasculares (DCV) continuam a ser principal causa de mortalidade no mundo e em Portugal, sendo encaradas atualmente como um dos mais importantes problemas de saúde pública. Como resposta a esta situação e em combinação com os avanços em diversos domínios científicos, surgiu um novo tipo de produtos alimentares, denominados alimentos funcionais. Estes produtos, cujo desenvolvimento aumentou consideravelmente ao longo da última década, além da função nutricional básica que possuem, oferecem também aos consumidores uma gama de compostos bioativos com efeitos benéficos e cardioprotetores para a saúde, reduzindo desta forma o risco de doenças DCV. Este trabalho teve como objetivo principal desenvolver uma bebida funcional substituta de café a partir de duas matrizes vegetais desvalorizadas e altamente disponíveis em Portugal, a bolota e a alfarroba. Para tal, foi necessário processar as amostras de forma a obter no final três bebidas funcionais, B1 (nem muito doce nem muito amarga), B2 (mais amarga) e B3 (mais doce), cada uma com diferentes formulações de bolota e alfarroba torradas, que se enquadrassem no gosto dos consumidores de café ou substitutos de café. De forma a avaliar os benefícios nutricionais e potenciais efeitos cardioprotetores para a saúde, foram efetuadas uma série de análises às bebidas desenvolvidas assim como também às matrizes cruas e às respetivas torras usadas para a preparação das bebidas. Neste sentido, foi realizada uma análise à composição química e nutricional das amostras: humidade/sólidos totais, cinzas, lípidos, proteínas, açúcares, fibras insolúveis, minerais e valor energético; foram avaliados, com recurso à espectrofotometria, os teores de compostos fenólicos totais (TPC), flavonoides totais (TFC), taninos condensados, produtos da reação de Maillard e atividade de sequestro dos radicais livres DPPH• e o ABTS•+, e por último foi feita uma análise à bioatividade através do estudo da capacidade de inibição das enzimas α-glucosidase e α-amilase. As bebidas foram ainda analisadas sensorialmente através de um inquérito efetuado a um grupo de 20 provadores não treinados, de forma a avaliar as características organoléticas dos produtos finais. Os resultados obtidos mostraram que as matrizes possuem um elevado valor nutricional, nomeadamente alto teor em fibras insolúveis, cerca de 19,0 ± 2,5% para a bolota e 31,3 ± 4,0% para a alfarroba, no entanto a alfarroba apresentou teores mais elevados em açúcares totais (31,3 ± 4,0%) quando comparado com outros frutos secos (castanha, amêndoa e avelã). Todas as amostras apresentaram capacidade antioxidante, comprovada essencialmente através dos seus altos teores em compostos fenólicos e de capacidade de sequestro dos radicais livres, nomeadamente o radical ABTS•+ . Deste modo, a bolota foi a matriz que obteve valores mais altos, cerca de 1551 ± 6 mg EAG/100 g de teor em TPC e apresentou um valor de IC50 para a atividade de sequestro do ABTS•+ de 6,04 ± 0,15 µg/mL, enquanto a alfarroba obteve valores de 859 ± 19 mg EAG/100 g e 203 ± 5 µg/mL, respetivamente. Em relação às bebidas, a B2 foi a que apresentou valores superiores de TPC, cerca de 275 ± 1,1 mg EAG/100 g, seguindo-se da B1 e B3 com os respetivos valores de 236 ± 1,1 mg EAG/100 g e 212 ± 1,6 mg EAG/100 g, por outro lado, a B3 (IC50 = 83,0 ± 2,1 µg/mL) obteve valores mais elevados para a atividade de sequestro do ABTS•+, seguido da B2 (IC50 = 65,7 ± 2,7 µg/mL) e B3 (IC50 = 65,3 ± 0,3 µg/mL). Em termos de bioatividades todas as amostras mostraram serem potenciais agentes antidiabéticos, uma vez que os extratos mostraram uma forte inibição da α-glucosidase, apresentando valores de IC50 entre 5,36 – 217 µg/mL. No entanto, não foram registadas quaisquer inibições para a α-amilase. Através da análise sensorial realizada, concluiu-se que os provadores tiveram mais preferência pela bebida B3, de seguida da B2 e por último a B1. Apesar de os provadores terem mostrado que não tinham muita intenção de comprar alguma das bebidas, a B3 foi a que obteve maior pontuação. Deste modo, este trabalho conseguiu mostrar o elevado valor nutricional das matrizes escolhidas, que se refletiu posteriormente na produção de bebidas funcionais, destacando-se a sua capacidade na prevenção e diminuição do risco de DCV, comprovando que estas bebidas poderão ser uma potencial alternativa ao café.
With the turn of the century, cardiovascular diseases (CVD) continue to be the leading cause of mortality in the world and Portugal is currently seen as one of the most critical public health problems. In response to this situation and advances in various scientific fields, a new type of food product called functional foods emerged. These products, whose development has increased considerably over the last decade, in addition to their primary nutritional function, also offer consumers a range of bioactive compounds with beneficial and cardioprotective effects on health, thus reducing the risk of CVD diseases. The main objective of this work was to develop a functional coffee substitute from two undervalued and highly available vegetable matrices in Portugal, acorns and carob. For this, it was necessary to process the samples in order to obtain, in the end, three functional drinks, B1 (neither too sweet nor too bitter), B2 (more bitter) and B3 (sweeter), each with different formulations of acorns and roasted carob, which fit the taste of coffee or coffee substitute consumers. Furthermore, to assess the nutritional benefits and potential cardioprotective effects on health, a series of analyses were carried out on the drinks developed, the raw matrices, and the respective roasts used to prepare the drinks. In this sense, an analysis of the chemical and nutritional composition of the samples was carried out: moisture/total solids, ash, lipids, proteins, sugars, insoluble fibres, minerals and energy value; total phenolic compounds (TPC), total flavonoids (TFC), condensed tannins, Maillard reaction products and free radical scavenging activity DPPH• and ABTS•+ were evaluated using spectrophotometry, and finally, an analysis of the bioactivity was performed by studying the ability to inhibit α-glucosidase and α-amylase enzymes. In addition, the drinks were also analyzed sensorially through a survey with a group of 20 untrained tasters to assess the organoleptic characteristics of the final products. The results showed that both the matrices have a high nutritional value, highlighting their high levels of insoluble fibre, around 19.0 ± 2.5% for acorn and 31.3 ± 4.0% for carob. However, carob had higher contents of total sugars (31.3 ± 4.0%) when compared to other nuts (chestnut, almond and hazelnut). Furthermore, all samples showed antioxidant capacity, proven essentially through their high levels of phenolic compounds and free radical scavenging capacity, in particular ABTS•+. Thus, acorn was the matrix that obtained the highest values, about 1551 ± 6 mg GAE/100 g of TPC content and presented an IC50 value for ABTS•+ scavenging activity of 6.04 ± 0.15 µg/mL, while carob obtained values of 859 ± 19 mg GAE/100 g and 203 ± 5 µg/mL, respectively. Regarding the drinks, B2 showed the highest TPC values, around 275 ± 1.1 mg GAE/100 g, followed by B1 and B3 with respective values of 236 ± 1.1 mg GAE/100 g and 212 ± 1, 6 mg GAE/100 g, on the other hand, B3 (IC50 = 83.0 ± 2.1 µg/mL) obtained the highest values for scavenging activity ABTS•+, followed by B2 (IC50 = 65.7 ± 2.7 µg/mL) and B3 (IC50 = 65.3 ± 0.3 µg/mL). Regarding bioactivities, all samples showed their potential as antidiabetic agents since the extracts showed strong inhibition of α-glucosidase, presenting IC50 values between 5.36 – 217 µg/mL. However, no inhibitions for α-amylase were recorded. The results showed that both the matrices and the drinks have a high nutritional value, highlighting their high levels of insoluble fibre in the matrices and the low energy value present in the drinks. In addition, all samples showed antioxidant capacity, proven essentially through their high levels of phenolic compounds and ability to scavenge free radicals, namely the ABTS•+ radical. Regarding bioactivities, all samples showed their potential as antidiabetic agents since the extracts showed strong inhibition of α-glucosidase. However, no inhibitions for α-amylase were recorded. Through the sensory analysis, it was concluded that the tasters had a greater preference for beverage B3, followed by B2 and B1. Even though the tasters showed that they had no intention of buying any of the drinks, B3 was the one with the highest score. This work showed the high nutritional value of the chosen matrices, which was later reflected in the production of functional drinks, highlighting their ability to prevent and reduce the risk of CVD, proving that these drinks could be a potential alternative to coffee.
With the turn of the century, cardiovascular diseases (CVD) continue to be the leading cause of mortality in the world and Portugal is currently seen as one of the most critical public health problems. In response to this situation and advances in various scientific fields, a new type of food product called functional foods emerged. These products, whose development has increased considerably over the last decade, in addition to their primary nutritional function, also offer consumers a range of bioactive compounds with beneficial and cardioprotective effects on health, thus reducing the risk of CVD diseases. The main objective of this work was to develop a functional coffee substitute from two undervalued and highly available vegetable matrices in Portugal, acorns and carob. For this, it was necessary to process the samples in order to obtain, in the end, three functional drinks, B1 (neither too sweet nor too bitter), B2 (more bitter) and B3 (sweeter), each with different formulations of acorns and roasted carob, which fit the taste of coffee or coffee substitute consumers. Furthermore, to assess the nutritional benefits and potential cardioprotective effects on health, a series of analyses were carried out on the drinks developed, the raw matrices, and the respective roasts used to prepare the drinks. In this sense, an analysis of the chemical and nutritional composition of the samples was carried out: moisture/total solids, ash, lipids, proteins, sugars, insoluble fibres, minerals and energy value; total phenolic compounds (TPC), total flavonoids (TFC), condensed tannins, Maillard reaction products and free radical scavenging activity DPPH• and ABTS•+ were evaluated using spectrophotometry, and finally, an analysis of the bioactivity was performed by studying the ability to inhibit α-glucosidase and α-amylase enzymes. In addition, the drinks were also analyzed sensorially through a survey with a group of 20 untrained tasters to assess the organoleptic characteristics of the final products. The results showed that both the matrices have a high nutritional value, highlighting their high levels of insoluble fibre, around 19.0 ± 2.5% for acorn and 31.3 ± 4.0% for carob. However, carob had higher contents of total sugars (31.3 ± 4.0%) when compared to other nuts (chestnut, almond and hazelnut). Furthermore, all samples showed antioxidant capacity, proven essentially through their high levels of phenolic compounds and free radical scavenging capacity, in particular ABTS•+. Thus, acorn was the matrix that obtained the highest values, about 1551 ± 6 mg GAE/100 g of TPC content and presented an IC50 value for ABTS•+ scavenging activity of 6.04 ± 0.15 µg/mL, while carob obtained values of 859 ± 19 mg GAE/100 g and 203 ± 5 µg/mL, respectively. Regarding the drinks, B2 showed the highest TPC values, around 275 ± 1.1 mg GAE/100 g, followed by B1 and B3 with respective values of 236 ± 1.1 mg GAE/100 g and 212 ± 1, 6 mg GAE/100 g, on the other hand, B3 (IC50 = 83.0 ± 2.1 µg/mL) obtained the highest values for scavenging activity ABTS•+, followed by B2 (IC50 = 65.7 ± 2.7 µg/mL) and B3 (IC50 = 65.3 ± 0.3 µg/mL). Regarding bioactivities, all samples showed their potential as antidiabetic agents since the extracts showed strong inhibition of α-glucosidase, presenting IC50 values between 5.36 – 217 µg/mL. However, no inhibitions for α-amylase were recorded. The results showed that both the matrices and the drinks have a high nutritional value, highlighting their high levels of insoluble fibre in the matrices and the low energy value present in the drinks. In addition, all samples showed antioxidant capacity, proven essentially through their high levels of phenolic compounds and ability to scavenge free radicals, namely the ABTS•+ radical. Regarding bioactivities, all samples showed their potential as antidiabetic agents since the extracts showed strong inhibition of α-glucosidase. However, no inhibitions for α-amylase were recorded. Through the sensory analysis, it was concluded that the tasters had a greater preference for beverage B3, followed by B2 and B1. Even though the tasters showed that they had no intention of buying any of the drinks, B3 was the one with the highest score. This work showed the high nutritional value of the chosen matrices, which was later reflected in the production of functional drinks, highlighting their ability to prevent and reduce the risk of CVD, proving that these drinks could be a potential alternative to coffee.
Description
Keywords
Sustentabilidade Doenças cardiovasculares Alimentos funcionais Valorização Bolota Alfarroba Sustainability Cardiovascular diseases Functional foods Valorization Acorns Carob