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- Strategy and design of innovation policy road mapping for microalgae-based foodsPublication . Barroca, Maria João; Florença, Sofia De Guiné E; Martins, Clara B.; Guiné, Raquel
- Extraction of Phenolic Compounds from Cherry Seeds: A Preliminary StudyPublication . Dulyanska, Yuliya; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Lima, Maria João; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Barroca, Maria João; Moreira da Silva, Aida; Guiné, Raquel P. F.Agri-food waste has proved to be a valuable bioresource that can be used to obtain a variety of valuable materials, ingredients and chemicals. The optimum conditions for extracting bioactive compounds from sweet cherry seeds (SCS) with different solvents and temperatures were tested in this work. The choice criteria were based on the most efficient extracting capacity while looking for cleaner techniques with lower health or environmental impacts. Some extracting solvents (methanol, ethanol and water) were tested in different combinations and temperatures. The obtained extracts were evaluated for total phenolic compounds and some families of phenolics as well, using spectrophotometric methods. The results obtained showed that the highest extraction of total phenolic compounds was at 70 °C with 60:40 ratio water:ethanol (2.65 mg GAE/g), while maximum flavonoids were obtained at 80 °C and 50% ethanolic aqueous solution (7.26 mg QE/g). The highest value for ortho-diphenols was 21.47 mg GAE/g for 50 °C and water:ethanol 50:50 solution. The highest proanthocyanidins and flavonols were obtained for 50:50 solution at 70 °C (6.43 mg CE/g and 3.88 mg QE/g, respectively), while the same solution at 80 °C allowed obtaining maximum phenolic acids (1.68 mg CAE/g). The extraction of anthocyanins was found to vary significantly with concentration and temperature, being highest in the range 35–40 °C, when using an 80:20 water:ethanol solution. Hierarchical clustering showed three clusters, while factor analysis resulted in two factors and four groups of samples. In conclusion, it was found that extracts obtained from sweet cherry seeds have relevant bioactive compounds with applications in the food, pharmaceutical or cosmetic industries.
- 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.
- Knowledge about consumption of milk: Study involving consumers from two European Countries – France and PortugalPublication . Bréjon, Marius; Tavares, Francisca; Florença, Sofia De Guiné E; C. Goncalves, J.; Barroca, Maria João; Guiné, RaquelMilk assumes a pivotal role in human nutrition from early stages of life, although when going into adulthood the consumption habits can vary according to different perceptions from the consumer or even due to the presence of some intolerances. In this context, this research focuses on the consumption knowledge about the composition and nutritional value of milk and its effect on human health. The objective was to investigate how informed are the French and Portuguese participants and detect similarities or differences according to the country. For this purpose, a questionnaire survey was set up to recruit participants from two countries: France and Portugal. The total number of participants was 543, of which 333 were French and 210 were Portuguese. For treatment of data basic statistics and tests were used to compare the results between the two countries, using the software SPSS. The results showed significant differences between the two countries in what concerns the participant’s knowledge about milk composition and nutritive value and also the effects of milk on human health. From the 13 items used to assess knowledge about composition and nutritive value of milk, significant differences were found between countries for six of them. Regarding the ten items used to evaluate the effects of milk on human health, significant differences were found for seven of them. As so, the knowledge about the effects on human health are more differentiated between the participants from France and Portugal, than the knowledge about the milk composition. Factor analysis showed six groups of questions, with good internal reliability (values of alpha varying from 0.707 to 0.825). It is concluded that participants from different countries, exposed to different environments (societal, political, or educational) can have different perceptions about milk and its effects on health.
- Development of a New Pasta Product by the Incorporation of Chestnut Flour and Bee PollenPublication . Brochard, Maëlys; Correia, Paula; Barroca, Maria João; Guiné, Raquel P. F.This work aimed at developing fortified pastas incorporating chestnut flour (25–55%) and powdered pollen (5–20%), either separately or in combination, as well as the characterization of the products obtained. To this, a physical characterization was carried out (analyzing texture and color), complemented with chemical analyses to determine the nutritional composition. Results showed that adding chestnut flour over 40% to wheat-flour pasta shortened optimum cooking time and lowered cooking yield, and the addition to pasta prepared with wheat flour and eggs maintained approximately constant the cooking yield. Additionally, the incorporation of pollen powder (up to 20%) in pasta prepared with wheat flour and water or fresh egg shortened the cooking time and cooking yield, in both fresh and dried pasta. The most suitable percentages of the new ingredients were 50% for chestnut and 10% for pollen. Comparing with the control pasta recipe (wheat flour and egg), the addition of chestnut flour (50%) or pollen powder (10%) increased stickiness, adhesiveness and the darkening of the final product (fresh or dried) but maintained the firmness of the pasta. The cooking of fresh or dried pasta enriched with both ingredients turned the pasta clearer and slightly stickier. On the other hand, the addition of chestnut flour and pollen powder in pasta formulation delivered a nutritionally balanced product with high fiber, vitamins and minerals. Overall, chestnut flour and powdered pollen represent promising ingredients for the development of functional fresh and dried pasta formulations.
- Evaluation of the antioxidant activity of extracts obtained form cherry seeds.Publication . Dulyanska, Y.; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Lima, M. J. Reis; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Barroca, Maria João; Silva, A. M.; Guiné, Raquel P. F.Annual cherry production in Portugal is around 19,000 tonnes, in an area of about 6,450 ha and covering about 11,100 farms, concentrated in some northern and central interior territories. It is also in these regions that in recent decades there has been a significant increase in farms specialized in the production of cherry, using new cultivars and new technologies in a business production model. Apart from being consumed in fresh form, cherries are used for many food preparations, like sweets, jellies or confectionary. In the plants that transform cherries, a significant amount of cherry seeds (also called cherry pits) is generated as residue or waste. The possible usage of these residues as raw material for extraction of compounds with antioxidant properties is beneficial in term of economic value as well as environmental impact. Hence, the objective of this work was to obtain extract rich in compounds with antioxidant activity from cherry seeds. The cherry seeds were obtained from a local waste management company, Nutrofertil, located in Tondela, in the district of Viseu (Portugal). They were grinded and then submitted to extraction procedures testing different operating conditions: magnetic stirrer versus ultrasound, different solvents (methanol, ethanol, water) and temperatures (from 35 ºC to 80 ºC). For the obtained extracts antioxidant activity 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 trice, and were expressed as mg Trolox equivalents per gram (mg TE/g). The results obtained for the different experimental conditions indicated that least efficient extractions at ambient temperature were obtained with methanol using magnetic stirrer and with water using ultrasounds, for which the antioxidant activities measured by the DPPH method were 0.26 and 0.33 mg TE/g and by the ABTS method were 0.82 and 0.86 mg TE/g, respectively. Most efficient methods were water:ethanol (at 50% concentration) and water (100%), using magnetic stirrer in both cases. Highest antioxidant activity was obtained for water:ethanol by the DPPH method (0.72 mg TE/g) and for water (100%) by the ABTS method (1.25 mg TE/g). Tests with different concentrations for the aqueous solutions of ethanol and at different temperatures revealed that with increasing concentration of water the antioxidant diminished, from 0.62 to 0.27 mg TE/g at 35 ºC using the DPPH method. Additionally, the variation in temperature allowed reaching a maximum extraction of compounds with antioxidant activity at 70 ºC and decreasing thereafter. The maximum values obtained were registered at 70 ºC for all cases and were 0.74 mg TE/g for the water:ethanol 50:50 (v/v) by the DPPH method, 2.16 mg TE/g for the water:ethanol 60:40 (v/v) by the ABTS method and 3.43 mg TE/g for the water:ethanol 60:40 (v/v) by the FRAP method. The results obtained by the different methods were concordant in terms of the observed trends but giving different values of the measured antioxidant activity, which is a common characteristic observed in these types of evaluation techniques. This research allowed establishing some operational conditions that should be selected in order to maximize the extraction of compounds with antioxidant activity from cherry seeds. The use of ultrasounds was not found beneficial and the magnetic stirrer technique revealed to be more useful. Also the use of methanol was not found suitable, which is a good point given that this solvent is more pollutant and has more problems of toxicity. With respect to temperature, it was found that temperatures higher than 70 ºC are not beneficial because they induce the degradation of some bioactive compounds thus reducing the antioxidant activity of thee extracts.
- Extração de compostos fenólicos de caroço de cerejaPublication . Dulyanska, Yuliya; Guiné, Raquel P. F.; valente, Luisa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Barroca, Maria João; Silva, Aida Moreira; Lima, M. J.Os resíduos agroalimentares provaram ser um biorecurso que pode ser usado para obter uma variedade de materiais, ingredientes e produtos químicos valiosos. Neste trabalho foram testadas as condições ótimas para extração de compostos bioativos dos caroços de cereja com diferentes solventes e temperaturas. Os critérios escolhidos basearam-se na capacidade de extração mais eficiente, buscando técnicas mais limpas e com menor impacto no meio ambiente. Alguns solventes de extração foram testados em diferentes combinações e temperaturas. Os extratos obtidos foram avaliados utilizando métodos espectrofotométricos quanto a compostos fenólicos totais, bem como algumas famílias de compostos fenólicos. Os resultados obtidos mostraram que a maior extração de compostos fenólicos totais foi a 70°C com razão água:etanol de 60:40 (% v/v) (2,65 mg GAE/g), enquanto os máximos resultados para flavonoides foram obtidos a 80°C e solução aquosa etanólica 50% (7,26 mg QE/g). O maior valor para orto-difenóis foi de 21,47 mg GAE/g para 50°C e solução água:etanol 50:50. As maiores quantidades de proantocianidinas e flavonóis foram obtidas para solução 50:50 a 70 °C (6,43 mg CE/g e 3,88 mg QE/g, respetivamente), enquanto a mesma solução a 80 °C permitiu obter o máximo de ácidos fenólicos (1,68 mg CAE/ g). A extração de antocianinas varia significativamente com a concentração e temperatura, sendo mais alta na faixa de 35-40 °C, quando se utiliza uma solução de água:etanol 80:20. Em conclusão, verificou-se que os extratos de caroços de cereja obtidos possuem compostos bioativos relevantes com aplicações nas indústrias alimentícia, farmacêutica ou cosmética.
- Apple Fermented Products: An Overview of Technology, Properties and Health EffectsPublication . Guiné, Raquel P. F.; Barroca, Maria João; Coldea, T. E.; Bartkiene, E.; Anjos, O.As an easily adapted culture, with overloaded production in some parts of the globe, ap- ples and their by-products are being redirected to pharmaceutical, canning and beverages indus- tries, both alcoholic and non-alcoholic. Fermentation is generally considered to increase the bioa- vailability of bioactive compounds found in apple, by impacting, through a high degree of changes, the product’s properties, including composition and health-promoting attributes, as well as their sensory profile. Probiotic apple beverages and apple vinegar are generally considered as safe and healthy products by the consumers. Recently, contributions to human health, both in vivo and in vitro studies, of non-alcoholic fermented apple-based products have been described. This review highlighted the advances in the process optimization of apple-based products considering vinegar, cider, pomace, probiotic beverages and spirits’ technologies. The different processing impacts on physical-chemical, nutritional and sensory profiles of these products are also presented. Addition- ally, the harmful effects of toxic compounds and strategies to limit their content in cider and apple spirits are illustrated. New trends of fermented apple-based products applicability in tangential in- dustries are summarized.
- Re-Thinking Table Salt Reduction in Bread with Halophyte Plant SolutionsPublication . Barroca, Maria João; Flores, Catarina; Ressurreição, Sandrine; Guiné, Raquel; Osório, Nádia; Moreira da Silva, AidaSodium intake higher than it is physiologically necessary has been associated with some non-communicable diseases such as hypertension, cardiovascular disease, and stroke. Bread is commonly consumed and is a major source of sodium in the human diet. Among the interventions to reduce the salt content in bread, the incorporation of salty taste halophyte powder could be a promising strategy. In the present work, Sarcocornia perennis was incorporated as a food ingredient to substitute the salt (sodium) of white wheat bread (1.2% NaCl/0.47% sodium, flour basis). Powdered dried S. perennis was incorporated into bread by replacing the same amount of sodium (0.47%, flour basis) and half of the sodium concentration (0.235%, flour basis), respectively, B100 and B50 bread samples. The bread samples were analyzed to evaluate the impact of the sodium chloride replacement by S. perennis powder on total baking loss, specific volume, crumb color, textural properties, microbial activity, nutritional and mineral composition and sensory evaluation. The incorporation of S. perennis increased the specific volume but had no relevant impact on the textural properties of bread. Furthermore, the substitution of sodium chloride by S. perennis powder allowed a more colored (greenish and yellowish) and dark crumb leading to a lower whiteness index. Compared with control bread, the addition of S. perennis powder promoted a significant increase of all bread’s nutrients and minerals, namely calcium, phosphor, iron, and manganese. Besides the improvement of bread quality, B100, and B50 bread samples were both sensorily well accepted and with similar scores to all the evaluated sensorial attributes. Moreover, the reduction of sodium to half (0.235% sodium (flour basis) in bread (B50) did not affect the acceptability of tasters, as compared with B100 (0.47% sodium (flour basis)). Both new bread formulation has microbiological quality as ready-to-eat product. However, taking into account greater stability over time for microbial spoilage, mainly caused by fungi and yeasts, B50 bread is more promising. The B50 bread sample is also a potential strategy to obtain a sodium reduction of 50% in bread, which could be essential to reduce the overall sodium daily intake and bring important economic and public health benefits.
- The panorama of usage of flowers for eating purposes: results from a questionnaire surveyPublication . Guiné, Raquel; Barroca, Maria João; Florença, SofiaThis work aimed to characterize the use of edible flowers for gastronomic purposes. A survey was done by internet in Portugal, and 147 valid questionnaires were completed, by individuals between 18 and 78 years old. The instrument included questions not only about consumption habits, but also about the knowledge relatively to edible flowers. The results revealed that flowers are appreciated when it comes to gastronomic preparations and could be consumed more frequently. They are recognized mostly for their organoleptic and decorative characteristics. Edible flowers are a part of modern gastronomic trends, and people are consuming this type of product more frequently, mostly fresh and particularly in salads. Nevertheless, it is important to consider the possible risks associated to their consumption, such as pesticides or toxicity, but fortunately the Portuguese consumers are aware of this problem. It is a reality that the market of edible flowers is expanding, and restaurants appear as important links on the chain of edible flowers consumption. Still, to further incentive the home preparation of recipes with edible flowers, it is necessary to provide cookbooks that include more edible flowers as in their recipes.