Chestnut and lemon balm based ingredients as natural preserving agents of the nutritional profile in matured “Serra da Estrela” cheese

Chestnut flowers, lemon balm plants and their decoctions were incorporated into "Serra da Estrela" cheese, to assess their potential to preserve its nutritional properties and provide new foodstuffs. The analyses were carried out after the normal ripening period of 1month and after 6months of storage. The most abundant nutrients were proteins and fats. The most abundant minerals were Ca and Na, while C16:0 and C18:1 were the main fatty acids. Saturated fatty acids were the most abundant, followed by the monounsaturated. Moisture seemed to be lower in the samples with the plants incorporated. The dried plants, when incorporated, seemed to be more efficient as preservers then the decoctions, although these better preserved the proteins. These plants can be regarded as promising natural preservers in foodstuffs cheese, given the preservation of key parameters and the slight impact on the nutritional value.

Basil as functional and preserving ingredient in “Serra da Estrela” cheese

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.

Os visitantes do parque Biológico de Gaia

Nascido em 1983, o Parque Biológico de Gaia (PBG) é das primeiras instituições de Educação Ambiental (EA) criadas em Portugal que se tem dedicado a desenvolver atividades de EA de forma articulada com as escolas ou alargadas a públicos diversificados que visitam o parque de forma autónoma. O PBG tem restaurado espaços naturais e humanizados – como as antigas quintas – promovendo a conservação da paisagem e contribuindo para assegurar o equilíbrio ecológico ao mesmo tempo que desenvolve um plano educativo constante para sensibilizar a população para os problemas ambientais e estimular comportamentos mais sustentáveis. Foi nesta instituição que realizamos o nosso estágio curricular do mestrado em Educação Ambiental da Escola Superior de Educação do Instituto Politécnico de Bragança, entre 5 de fevereiro e 18 de maio de 2016. O presente Relatório apresenta o trabalho desenvolvido, com particular destaque para os resultados da investigação sobre as práticas de Educação Ambiental concretizadas pela instituição. As técnicas utilizadas na recolha de dados foram a observação, a análise documental e o inquérito por questionário. Consideraram-se os Relatórios de Contas desde 2010 e analisou-se um questionário de satisfação aplicado pelo PBG, referente aos anos de 2012 a 2015; além disso, criou-se um questionário para conhecer as perceções dos visitantes sobre as práticas de Educação Ambiental, que foi aplicado durante visitas livres ao PBG efetuado no período de estágio. Os dados foram tratados numa perspetiva estatística descritiva, tendo os dados qualitativos sido previamente sujeitos a análise de conteúdo. Recorreu-se à utilização do software Microsoft Excel. Os resultados mostram uma opinião francamente positiva sobre o PBG por parte dos visitantes, que os quais valorizam a qualidade ambiental do Parque, as atividades para crianças e reconhecem que ganharam interesse pelo Ambiente após o contacto com o PBG. Um bom indicador dessa apreciação é que uma larga maioria de visitantes pensa voltar e aconselha a visita. Outro dado interessante obtido foi que várias respostas referem o contacto com o PBG enquanto crianças e jovens. Do ponto de vista pessoal, o estágio foi um desafio importante, permitiu-nos confrontar os conhecimentos teóricos com a realidade e adquirir uma experiência profissional relevante.

Antioxidant profile of Stevia rebaudiana Bertoni cultivated in Portugal and submitted to different conservation conditions

The demand for natural sweeteners has been gaining more and more importance due to the great controversy associated with the use of some synthetic sweeteners as cyclamates, aspartame and acesulfame-K. The steviol glycosides (E 960) are a group of natural sweeteners of generalized use; these compounds are obtained from Stevia rebaudiana Bertoni, a sweet plant native from South America (Carocho et al., 2015). However, Stevia rebaudiana Bertoni may have other uses to be exploited, in particular due to its antioxidant capacity. This plant is already produced in Portugal but it is important to evaluate if the plant chemical composition is maintained regardless of culture conditions. Therefore, in this study, stevia samples were cultivated in Braganca (northeastern of Portugal) in a field trial with defined culture conditions. After harvesting, the plants were submitted to two different treatments: kept fresh by freezing (-20°C) and oven-dried (30°C). The antioxidant profile of the samples was studied through evaluation of free radicals scavenging activity, reducing power, phenolic compounds (HPLC-DAD-ESI/MS), tocopherols (HPLC-fluorescence) and free sugars (HPLC-RI). Significant differences were observed: while oven-dried samples showed the highest antioxidant activity and phenolic compounds concentration (mainly 5-O-caffeoylquinic acid and 3,5-O-dicaffeoylquinic acid), the frozen fresh samples had the highest values of total tocopherols and total sugars. These results confirm that the plants grown in Bragança have excellent bioactive secondary metabolites responsible for the observed antioxidant capacity.