CERNAS - Artigo em ata de evento científico internacional
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- Numerical study of the optimal nozzle width and jet orientation in a downward blowing air curtainPublication . C. Goncalves, J.; Costa, José Joaquim Da; Gameiro Lopes, Antonio; Figueiredo, A. RuiThis paper presents a numerical study of the performance of an air curtain device (ACD) installed on top of the access door of a refrigerated room, aiming to quantify the influence of some parameters (nozzle width, initial orientation and discharge velocity of the jet) towards the maximization of the sealing effect. For this purpose, a numerical model was developed to simulate the turbulent non-isothermal 3D airflow generated by the ACD jet, focusing on the period after the door is opened. The situation when the ACD is switched off is taken as the reference for the performance evaluation. The results allow identifying an optimum jet nozzle width corresponding to maximum sealing efficiency and lower jet airflow rate (lower energy consumption in the air curtain operation). For the present conditions (ACD installed outside the refrigerated room), the sealing efficiency is highest with the ACD oriented vertically and is practically unaffected if the jet discharge is directed towards the warmer space. On the contrary, a jet discharged towards the cooler space is very detrimental to the ACD sealing effect
- Sources of information about dietary fibre: a cross-sectional survey of 1034 respondents from across CroatiaPublication . Sarić, MM; Ljubičić, M; Guiné, RaquelNutritional knowledge and attitudes are important for the consumption of healthy food. Well-informed consumers could have a higher chance to select food rich in nutrients like dietary fibre (DF), which is recognized as one of the major determinants for the improvement of health. Due to that reason, health institutions (health centres and hospitals); media (radio, television and internet); education institutions (schools) and education materials (books and magazines) as main sources of information through which people become aware or acquire knowledge of DF, were considered. Cross-sectional survey was conducted from October 2014 to March 2015 on a non-probabilistic sample of 1034 participants from Croatia. The instrument was a questionnaire of self-response, aimed at collecting information on knowledge, attitudes and sources about DF. Descriptive and inferential statistics were performed using SPSS 22.0 software considering a level of significance of 5%. The internet, the preferred source of information, got the highest scores for urban areas, university level of education and for female gender. The radio, the least scored source of information, was preferred by men and with lower education (primary school). People get most information through the internet due to easy access, but it could be detected as a possible risk given the impossibility to control information made public on the internet. It is very important to increase the impact of health centres and schools as adequately controlled public health informing sources.
- Hazelnuts: a valuable resourecePublication . Guiné, Raquel; Correia, PaulaHazel (Corylus avellana L.) nutshell is one of the most consumed and most appreciated nut fruit all over the world. It is believed to have constituted a basic food in early prehistory, in temperate zones of the globe, such as for example Europe. Presently the hazelnut production is mainly concentrated on the Black Sea coast of Turkey, but other countries are also important producers, like for example Portugal, situated on the western Europe, in the Iberian Peninsula. The objective of this talk is to make a review about the worldwide importance of hazelnut, their usages, including gastronomic and industrial applications, as well as some ways that allow adding value to this fruit, making it an even more valuable resource. The advantages include higher income for produces, lower environmental impacts and valorisation of residues improving sustainability and providing valuable products for consumers and/or ingredients to incorporate into those products.
- Hazelnut Storage at Controlled Conditions with Different Packaging MaterialsPublication . Correia, Paula; Filipe, Ana; Ramalhosa, Elsa; Guiné, RaquelThe nutritional and organoleptic quality of hazelnuts can be greatly influenced by storage conditions. The aim of this study was to evaluate the effect of vacuum packaging and raffia bags on the physicochemical characteristics of hazelnuts, both in shelled and unshelled (kernel) fruits when stored under controlled conditions of temperature (25ºC) and relative humidity (65%), simulating the average annual conditions of a tropical country. The following properties were evaluated: moisture, water activity (aw), color and fat oxidative stability, both in the initial sample and also after 6 and 12 months of storage. After 6 months, the gradual degradation of the shelled and without shell (kernel) hazelnuts stored in the raffia bags was clear and they were completely damaged at the end of 12 months of storage. There was a decrease in the initial values of water activity and moisture content (being 0.76 and 8.1% respectively) in the first 6 months of storage. The aw varied significantly after 6 months, between 0.60 and 0.71 in the samples packed in raffia. The moisture of vacuum packed fruits decreased from 6 to 12 months, reaching values between 4.3% and 4.8%. As far as color is concerned, there were generally no significant variations in the L *, a * and b* coordinates during storage in the hazelnut shell or kernel. Fat stability decreased over the shelf life, with a marked decrease in the first 6 months for hazelnuts in raffia bags and after 6 months for vacuum packed ones, with vacuum packed hazelnuts showing higher oxidative stability. From this study it can be concluded that vacuum packaging allows the best preservation of hazelnuts, with color being the least affected property. Both packaging and length of storage influence the quality of the hazelnuts.
- Case study of a project-based learning experience at the Polytechnic of Viseu, PortugalPublication . Delplancq, Véronique; Amante, Susana; Costa, Cristina Amaro Da; Costa Lopes, Ana Maria; Coutinho, Emília; Fidalgo, Susana; Gillain, Romain; Lopez, Patricia; Oliveira, Isabel; Pereira, José; Relvas, Susana; Roush, PaulaPedagogical innovation is at the centre of higher education (HE) priorities, with a view to renewing its practices and thus motivating students and providing experiences in line with their professional context. Improvement in foreign languages (FL), especially with students who are not likely to receive further language training, requires awareness of this query, inasmuch as competences in FL in the work environment are unanimously recognized as vital and so rightly included in the training plans. The project-based learning approach in an interdisciplinary and collaborative work perspective, using multimodality in communication, is a consistent asset that allows for work to be carried out, comprising the various dimensions of language in French and English, in their connections with cognitive representations. JASM (Open window onto the world: foreign languages, multimodal creativity and pedagogical innovation in higher education) project aims to develop an experience of active pedagogy at the School of Education of Viseu from the Polytechnic Institute of Viseu (Portugal)with undergraduate students in Media Studies enrolled in the various FL curricular units. Among the subjects of the study plan, students work on photography, digital art and cultural communication. The students start off by collecting information on the cultural and linguistic diversity of the city of Viseu (Beira Alta, Portugal). The project enhances the acquisition of multilingual skills and the development of plurilingual awareness, due to the attention given to the various dimensions of language (aesthetic and emotional, in addition to cognitive), in a creative, collaborative and interdisciplinary work environment. Based on an interview, students write the story (in French and English) of the life of migrants. Through captioned photographs, students highlight the aspect of the migrant’s family life which stands out the most. Based on an object (associated with religion, a tradition or with a ritual), students create an animated film, also in both languages (exploration of material culture and digital scenography). The outcome of such productions will be the subject of publications on social media, exhibitions, also being displayed at events and in an e-book. In this project, the topic of interdisciplinarity is highlighted, combining FL with digital art. The evolution, both of the students’ learning and of the teachers’ role in the whole process, is assessed, using tests carried out at the beginning and at the end of the project, including monitoring in the middle of the development of the project.
- Food behavior, social aspects, and nutritional status in romaniaPublication . Tarcea, M.; Matran, I. M.; Martin-Hadmas, R.; Fazakas, Z.; Guiné, Raquel P. F.Introduction. Health status is directly linked with nutritional status, life style and food behaviour. There are 4 Health Indicators: Health Conscience, Health Information Orientation, Health-Oriented Beliefs, and Healthy Activities. People who are health conscious have a positive attitude towards preventive measures such as healthy eating. Health information refers to the extent to which an individual is willing to seek health information. At the cognitive level, health orientation is manifested in the field of health beliefs, which refers to the specific cognitions held by individuals about health behaviors. Also, health-oriented individuals are more likely to engage in healthy activities than other people in the population. The four aspects of the health orientation mentioned suggest the differences between individuals in the context of their sources of information in the health field. Our aim was to evaluate connections between social characteristics, nutritional status data and food behaviour, in a Romanian population sample. Material and methods. We followed a qualitative cross-sectional study based on screening of 751 Romanian adults from different regions of our country, which was carried out in 2018. We used a validated questionnaire from an international project, based on 26 specific questions, filled in online, regarding their nutritional and social data completed by their attitudes and information towards food behaviour. In our group, 68.7% were women, one quarter had over 50 years old, 82.3% were from urban areas and almost 2/3rds were higly educated. Results. We obtained a positive correlation between demographic parameters and the BMI, also healthy food behaviors were more frequent at women versus man. On the opposite, the confidence of men upon the information about healthy eating from the internet was higher than that of women. The number of hours/day spent watching TV or in front of the computer was positively correlated with age and also with their BMI. A high education level was significantly positively associated with healthier choices regarding nutrition practices. Health status in relation with nutritional status showed us that the most concerned group for their diet was those who suffered from different pathologies especially cardiovascular disorders. We obtained no significant associations among BMI, environment, current professional activity, responsibility for eating, and physical activity. Conclusions. Nutritionists, specialists in medicine, and food stakeholders should promote healthy diets through adequate sources of information aimed at target groups. Multidisciplinary teams should develop a more efficient strategy to motivate people to make healthy eating choices and improve population food behavior.
- Drying of Maritime Plants: Effect on Antioxidant ActivityPublication . Guiné, Raquel P. F.; Barroca, M. J.; Mansinhos, I.; Silva, A. M.Salicornia and Sarcocornia belong to the same family and have similar morphological and organoleptic properties. [1]. The objective of this work was to evaluate the antioxidant activity extracts obtained from the plants in the fresh state and after being dried. Their extracts may represent a valuable source for developing novel food products (antioxidant-enriched foods), and/or table salt substitutes that satisfy the desires of consumers in terms of health benefits and sensorial acceptance. The plants (Salicornia macrostachya Moric. and Sarcocornia perennis) were collected from Portuguese salt pans, in the central region of Portugal and the aerial parts were used as raw material. The drying of plants was performed in a pilot tray drier at 40 ºC and air velocity of 1.5 ms -1 , for approximately three days. The initial moisture content was 92.30% and 84.24%, respectively, for Salicornia and Sarcocornia. The drying was carried out until reaching a final moisture content of 5%. The antioxidant activity was measured with DPPH method. Regarding the DPPH method, the results showed that the incubation time of 15 minutes is enough to measure the DPPH scavenging activity in halophyte extracts in the tested range of extract concentrations (Figure 1). However, the time defined to measure the DPPH scavenging activity was fixed at 30 minutes, since this was the common time in different laboratorial protocols. For Salicornia, the values of inhibition IC 50 were 1.09 and 1.12 mg/mL for the fresh and dried samples, respectively. For Sarcocornia, the values of IC 50 were 1.42 and 1.02 mg/mL for the fresh and dried samples, respectively. The results showed that the convective air-drying process at 40 ºC is adequate to improve the shelf life of the two halophyte plants, since the antioxidant activity was maintained or even improved as compared with the fresh samples. This might be due to a response of the plant to the stress induced by the heat and humidity conditions in the drying chamber. In this way, it was concluded that both studied halophyte plants constitute a valuable source of natural antioxidants when they are consumed as foods either in the fresh or dried states. Additionally, their extracts may represent a valuable source for developing novel antioxidant-enriched food products aimed to meet the desires of consumers who seek for health-beneficial foods.
- Food safety in portuguese Companies in Covid-19 Pandemic ContextPublication . C. Goncalves, J.; Guiné, Raquel P. F.; Correia, Paula; Tomasevic, I.; Djekic, I.
- Os Insetos Comestíveis e a SustentabilidadePublication . Florença, Sofia De Guiné E; Correia, Paula; Costa, Cristina Amaro Da; Guiné, Raquel P. F.Alimentar-se é uma necessidade básica para todos os seres humanos. No entanto, atender a essa necessidade e ao mesmo tempo contribuir para a manutenção dos ecossistemas, ainda é um desafio. Os sistemas alimentares apoderam-se, atualmente, de mais de 30% da terra, 70% da água potável e 20% da energia, contribuindo amplamente para a perda de biodiversidade, água e terra à escala global. Este estudo investigou o conhecimento e atitudes de uma amostra de portugueses relativamente aos insetos comestíveis. Para tal usou-se um questionário, colhendo-se respostas de 213 participantes. Para o tratamento dos dados usaram-se técnicas estatísticas e o software SPSS (versão 26). Os resultados indicaram que as pessoas tendem a ter perceções corretas sobre as questões de sustentabilidade associadas ao uso de insetos como fontes alternativas de proteína. Em relação ao consumo de insetos comestíveis, constatou-se que apenas uma pequena parte dos participantes já havia comido (16%), principalmente no exterior, por iniciativa própria, em restaurante ou em festa ou evento. Além disso, verificou-se que a relutância em consumir insetos é maior se forem inteiros, mas quando se transformam em ingredientes utilizados em formulações de alimentos, o nível de aceitação aumenta. Como conclusão final, observou-se que os portugueses ainda apresentam alguma resistência em aderir ao uso de insetos como substitutos de proteína de origem animal, mas o mercado de produtos à base de insetos pode ser uma boa alternativa para contornar a neofobia associada a este tipo de alimento.
- Extraction of Phenolic Compounds with Antioxidant Activity from Cherry Seeds: Preliminary StudyPublication . Guiné, Raquel P. F.; Castelão, D.; Dulyanska, Y.; Ferrão, A. C.; Correia, Paula; Esteves, Bruno; Domingos, Idalina; Ferreira, José; Cruz-Lopes, LuisaThe food processing industry is responsible for the generation of a significant amount of wastes and by-products, resulting from the transformation processes applied to food. These residues are highly rich in bioactive compounds with antioxidant activity, like for example the phenolic compounds [1]. To recover these compounds from the residues, extraction operations usually apply, but their optimization is important to maximize yield, minimize costs and reduce the environmental impacts. One of the main issues is related with the use of organic solvents derived from petroleum [2]. The objective of this study was to test different extraction conditions to obtain phenolic compounds from cherry seeds. For this the seeds used were pre-dried in the sun and grounded, and the powder was then dried in a stove for 24 hours at a temperature of 40 ºC. The extraction was performed using different solutions: water, methanol, ethanol:water (in variable percentages from 50% to 100% water) and ultrasounds. Also, the temperature was varied from 35 to 80 ºC. The total phenolic compounds (TPC), anthocyanins, flavonoids and antioxidant activity (DPPH and ABTS methods) were measured using spectroscopic methods. The results showed that the extraction of total phenolic compounds was higher for extraction with water or mixtures of water and ethanol, rather than with methanol or water plus ultrasounds (Fig.1). Additionally, testing different temperatures and percentages of water, it was verified that maximum extraction of phenolic compounds was obtained for 70 ºC, and using an extraction solution of ethanol:water (40:60, % v:v), which was 2.65 mg/g (galic acid equivalent). Under these conditions, the anthocyanins were 0.65 mg/g, and flavonoids were 1.05 mg/g (malvidin-3-glucoside equivalent). The antioxidant activity was 2.26 mg/g measured by ABTS method and 0.65 mg/g measured by DPPH method, in both cases expressed as Trolox equivalents. In this way it was possible to obtain extracts rich in phenolic compounds with antioxidant activity, using an aqueous solution with 40% ethanol, and by performing the extraction at 70 ºC and using magnetic stirrer.