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- Evaluating phenolic compounds in ethanolic extracts of cherry pitPublication . Dulyanska, Y.; Lima, M. J. Reis; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Barroca, Maria João; Silva, A.; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Guiné, Raquel P. F.The climatic conditions in Portugal favoured the adaptation of the cherry tree allowing its cultivation in several regions of the country. Studies made by the Portuguese Bureau of Statistics – INE 1, showed that the Portuguese sweet cherry production has an implemented area of 6,387 ha, producing 9,241 tons of this fruit. Its production extends mainly to two regions: the North (area of 3,099 ha and production of 6,586 tons) and the Centre (3,177 ha and 2,510 tons), while the rest of the country and islands accounts for only 1.6% of the cherry production. There are several varieties of cherry in Portugal, and the most important traditionally cultivated are: “Saco da Cova da Beira”, “Saco do Douro”, “Lisboeta”, “São Julião”, Big Burlat, Maring, Napoleon-big-foot and Big Windsor, being the first four varieties native from Portugal. Cova da Beira is the most important cherry production area in Portugal, either in terms of production volume, or also in area. Additionally, the evolution of technological indicators associated with culture reveals a high degree of specialization of the “new” farms, almost always associated with other fruit crops, which coexist in a very significant number of smaller farms, of a family type, that constitute the historical legacy of cherry production on the hillside north of the Serra da Gardunha. Sweet cherry seeds result from processing sweet cherry for sweets, juices and jams’ production. Generally, seeds are considered a production waste, which gains a strong interest due to the environmental aspects related to waste disposal 2. Additionally, it is well documented that production waste, such as peels, seeds, and pomace, contain high-value bioactive compounds 3. Hence, the present work investigated the extraction of some bioactive compounds from cherry pits that originate from food manufacturing industries. The waste management company Nutrofertil, located in Portugal, namely in the district of Viseu (Tondela), provided the Seeds of Sweet Cherry (SSC) for this study. The seeds were milled and dried for stability and then used for extraction with ethanolic solutions at different percentages (from 50 to 100% water v/v). Variable temperatures were also tested and the extracts were used for quantification of phenolic compounds through spectrophotometric techniques. The material was analysed to verify that it was exempt of hydrocyanic acid. Statistical techniques were used to treat the data: (a) Hierarchical cluster analysis using squared Euclidean distance and average linkage between groups method; (b) Principal component factor analysis with Varimax rotation. The results indicated that extraction at 40 ºC with magnetic stirring and using aqueous solutions of ethanol (water:ethanol ratio = 80:20, % v/v) constitute a separate cluster. Also, extracts obtained with similar conditions but for the temperature of 35 ºC constitute another isolated cluster. Factor analysis revealed a grouping structure with four clearly distinct clusters (Figure 1). Group G1 accounts for the samples with water:ethanol 80:20 (% v/v) and a temperature of 35 ºC, corresponding to the extraction of higher amounts of anthocyanins. Group G3 includes the extractions with 100% water at 70 ºC (G3), with lowest contents of anthocyanins and flavonols. The remaining groups are divergent according to the values of total phenolic compounds. In group G4 are included samples in which were quantified high values for total phenolic compounds, flavonoids, proanthocyanidins, ortho-diphenols and phenolic acids, while G2 corresponds to samples with smaller amounts of those compounds. In conclusion, investigating the extraction potential of different conditions it was allowed to optimize the experimental conditions more favourable to maximize the recovery of certain bioactive compounds, which can have multiple applications as antioxidant substances after rigorous quality control regarding possible concentrations of hydrocyanic acid.
- The impact of extraction temperature and solution concentration on the antioxidant activity of sweet cherry seeds’ extractsPublication . Dulyanska, Y.; Cunha, Margarida; Lima, M. J.; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Barroca, Maria João; Silva, A.; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Guiné, Raquel P. F.Sweet cherry seeds, a valuable lignin-cellulose raw material for the production of polyurethane foams 1, are also a significant source of different phenolic compounds 2 and can be a good source of natural antioxidants, which can play an important role in preventing the formation of free radicals and protection against degenerative diseases. Considering sustainability, the main objective of this project was the use of cherry by-products (seeds) to produce extracts rich in antioxidant compounds. In this work, the seed extracts were obtained with the addition of different combinations of ethanolic solution (water:ethanol ratios - 50:50; 60:40; 80:20; 100:0 v:v) and at different temperatures (35, 50, 70 and 80 °C), all under magnetic stirring for 40 minutes. Then, the antioxidant activity of the extracts was evaluated through spectrophotometric methods, using the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid)) radicals, and also the Ferric Reducing Antioxidant Power Assay (FRAP). All measurements were replicated at least in triplicates and were expressed as mg Trolox equivalents per gram (mg TE/g). Statistical analysis was performed using the JAVA software. ANOVA tests show that there is a statistically significant effect of temperature, water percentage and temperature on the antioxidant activity evaluated by the three methods used (p> 0.001 in all tests). The percentage of water is the variable that most contributes to this effect. Individual Post Hoc comparisons show, for all tests, that in general the temperatures induce differences in antioxidant activity, except 70 °C and 80 °C in DPPH and FRAP, and 80 °C and 50 °C in ABTS. Regarding the percentage of water, it was found that all samples are different from each other, except the FRAP, in which no significant differences between 50 and 60% of water were found. In conclusion, no major differences between the ABTS, DPPH and FRAP methods were found. Temperature and percentage of water have a significant effect on the concentration of antioxidant activity in all methods. In that way, the cherry pit is a good by-product to produce extracts with high content of antioxidant activity, being that the 70° C with 50:50 and 60:40 water:ethanol solutions are the most favorable conditions to potentiate the antioxidant activity.
- Estudo Comparativo sobre o consume de produtos alimentares sustentáveis em Portugal e na turquia durante a pandemia de Covid-19Publication . Guiné, Raquel P. F.; Costa, D.; Celik, S.; Florença, Sofia De Guiné E; Ferreira, Manuela; Cardoso, Ana Paula; Cetin, S.; Costa, Cristina Amaro DaResumo: Os sistemas de agricultura biológica são sugeridos para substituir a agricultura convencional de forma a minimizar o impacto ambiental e preservar a biodiversidade. Pretendeu-se investigar as tendências dos consumidores e os hábitos de consumo de alimentos obtidos através da agricultura biológica em Portugal e na Turquia. Foi utilizado um inquérito por questionário online. Para o tratamento de dados, foram utilizadas técnicas estatísticas básicas complementadas com uma classificação em árvore destinada a avaliar a influência de fatores sociodemográficos no conhecimento sobre este tipo de alimentos. Os resultados mostraram que os padrões de consumo são semelhantes em ambos os países, com muitos participantes a consumir alimentos biológicos, especialmente vegetais e frutas, consumindo-os na sua maioria 2 ou 3 refeições por semana. As motivações mais fortes para consumir incluem benefícios para a saúde humana e menores impactos ambientais, enquanto a razão mais substancial para não consumir é o preço. Em ambos os países as pessoas têm bons conhecimentos sobre as vantagens dos alimentos biológicos em relação aos convencionais. Finalmente, a perceção do valor atribuído pela sociedade aos alimentos biológicos foi consideravelmente maior em Portugal. Estes resultados confirmam as tendências atuais dos consumidores para fazer escolhas alimentares mais sustentáveis, motivadas pelo percecionado impacto negativo da agricultura convencional nos ecossistemas e na saúde humana.
- Estudo Internacional do nível de conhecimento sobre insetos comestíveisPublication . Guiné, Raquel P. F.; Florença, Sofia De Guiné E; Ferreira, Manuela; Costa, Cristina Amaro Da; Correia, Paula; Cardoso, Ana Paula; Campos, Sofia; Anjos, Ofélia; Chuck-Hernandez, C.; Saric, M.; Papageorgiou, M.; Baro, J.; Korzeniowska, M.; Bizjak, M.; Bartkiene, E.; Tarcea, M.; Boustani, N.; Djekić, I.; Klava, D.; Damarli, E.Resumo: Introdução – O consumo de insetos é uma prática tradicional ao longo da história humana, mas o seu consumo é muito variável de acordo com a região do globo. Objetivos – Pretendeu-se investigar o nível de conhecimento sobre insetos comestíveis numa amostra de participantes de treze países. Métodos – Os dados foram recolhidos em 2021 por questionário online. Obtiveram-se 6899 respostas válidas. Para a análise dos dados usou-se análise fatorial, análise de clusters e testes qui-quadrado. Resultados – Foram usados 27 itens para medir o conhecimento, utilizando uma escala do tipo Likert de cinco pontos. Aplicando análise fatorial obteve-se uma solução que explica 55% da variância total observada. Esta inclui 4 fatores que retiveram 22 dos 27 itens iniciais: F1 = Sustentabilidade (8 it); F2 = Nutrição (8 it); F3 = Fatores de Produção (2 it); F4 = Preocupações com a Saúde (4 it). A análise de clusters produziu três grupos de participantes (indivíduos 'receosos', 'agricultores' e 'ecológicos'). A caracterização dos clusters revelou que a idade não influenciou a inclusão nos clusters, enquanto sexo, escolaridade, país, meio onde reside, área profissional e rendimento influenciaram a composição dos clusters. Conclusões – O nível de conhecimento sobre insetos comestíveis é altamente variável de acordo com as características individuais e localização geográfica. Por outro lado, a segmentação permitiu identificar 3 tipos de indivíduos, 'receosos', 'agricultores' e 'ecológicos'.