Browsing by Author "Lima, Maria João"
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- Acolhimento na Escola Superior de Saúde de Viseu : Roteiro do Programa de Mentoria Ano Letivo 2024-2025Publication . Coutinho, Emília; Lemos, Carlos Miguel Correia; Batista, Susana; Rocha, Paula; Cordeiro, Manuel; Condeço, Luís; Lemos, Micaela Correia; Tomás, Luísa da Glória Sassoma; Simões, Marisa Mourinho; Domingues, Beatriz Gomes; Freitas, Joana Filipa Figueiredo; Duarte, Tatiana Gonçalves; Sousa, Ana Margarida; Silva, Annylise das Neves Fonseca e; Guedes, Beatriz Gonçalves; Giestas, Diana Beatriz Esteves; Guímaro, Ema Fonseca; Matos, Ema Lima; Filipe, Lara Bento; Coelho, Margarida Costa; Lima, Maria João; Viana, Maria João Martins; Santos, Matilde Lopes dos; Cardoso, Sara Filipa Sousa Rocha; Cardoso, Sofia Fernandes; Santos, Ana Filipa Néri dos; Ribeiro, Ana Rosa Jesus; Gomes, Bárbara Rosa; Oliveira, Beatriz Azevedo; Gomes, Carina da Silva; Silva, Carlos Rafael; Henriques, Francisca Lúzia; Albuquerque, Gonçalo Costa; Andrade, João Gabriel Jeovani; Fernandes, Jorge Miguel Cardoso; Ferreira, Pedro Miguel Fernandes; Bento, Raquel Pereira; Coimbra, Sílvia Duarte; Almeida, Sofia
- Analysis of the alterations in the color of pears dried under different systems.Publication . Guiné, Raquel; Lima, Maria João; Barroca, Maria João; Ferreira Wessel, DulcineiaIn Portugal, pears are traditionally dried by a direct sun-exposure method. However, because of the disadvantages associated with this procedure, alternative dryings are being tested. The objectives of this study were to evaluate how drying influences the color of pears, and to compare the products dried through different systems, to evaluate which one allows obtaining a product as much as possible with the same color of the traditional pears. From the results obtained was possible to see that dryings in systems with exposure to the sun (through glass) allow obtaining products that do not differ much from the traditional dried pears.
- Aveleira: Estado da TransformaçãoPublication . Correia, Paula; Lima, Maria João; Guiné, RaquelCom este estudo pretende-se abordar a temática da transformação da avelã, desde a sua armazenagem até ao consumo pelo consumidor final. Após a colheita e secagem destes frutos torna-se necessário a sua armazenagem e conservação de modo a garantir a sua qualidade e integridade, evitando alterações irreversíveis, nomeadamente a perda de valor nutricional e alterações nos seus atributos sensoriais, originando perdas substanciais em termos de rendimento. Devido às suas caraterísticas químicas, a avelã apresenta-se como um alimento importante para a saúde e nutrição humana, nomeadamente devido à quantidade e qualidade dos seus lípidos, fibra, vitaminas e elementos minerais. O consumo de avelã está amplamente difundido pelo mundo, sendo consumida em fresco ou processado, contribuindo deste modo para a valorização destes frutos. A apetência para a transformação deve-se essencialmente às suas caraterísticas organoléticas, levando a que seja uma matéria-prima importante na elaboração de produtos bastante consumidos e apreciados, como é o caso dos cremes de avelã e chocolate para barrar o pão, bem como a sua introdução na manufatura de chocolates com avelãs.
- Comparative study of pear drying using solar stove and tunnel dryingPublication . Guiné, Raquel; Barroca, Maria João; Lopes, Paulo; Silva, Vitor; Lima, Maria João; Ferreira, DulcineiaSun-dried pears of Portuguese S. Bartolomeu variety are relatively small fruits with peculiar organolephtic characteristics. The open sun drying has some disadvantages related with drying efficiency and food safety. However the drying with an economic and friendly energy is an important characteristic of the drying methods and therefore several attempts have been made to develop processes using solar drying. The present work studies two types of pears drying, namely solar stove and tunnel drying, using the solar energy and simultaneously reducing the exposure of fruits to contamination agents. Both processes were conducted in two consecutive years to analyse if the behaviour of each drying method shows evidence of a similar pattern. The results enable us to conclude that the variation of normalized moisture of pears with the drying time follows a linear relationship while an exponential decay is observed in the tunnel drying. Despite the different climatic conditions, it is possible still to observe that the behavior of each process is quite similar in both consecutive years. However, in the year of 2008 the drying tends to be faster in both processes. In addition, it is also possible to conclude that the Total Soluble Solids/Acidity ratio has a similar behavior along the drying in the two years for each process. However, the decrease of acidity of pears in solar stove is more pronounced than the TSS and consequently a higher ratio of Total Soluble Solids/Acidity is observed along the solar stove drying when compared with the tunnel drying.
- Comparative study of the composition of pears dried under different methods.Publication . Loureiro, Andreia; Guiné, Raquel; Lima, Maria João; Ferreira, DulcieniaDrying of agricultural products under direct sunlight is the traditional way of preserving many fruits and vegetables. The use of the sun to dry foods has the advantage of being cheap. However there are some disadvantages, such as intensive labor and slowness of the process. Moreover, several factors make solar drying less attractive, such as: climatic conditions, product pollution from dust or from animal contamination, and other types of infestation and microbial or mould contamination in humid environments [1]. In Portugal, pears of the variety S. Bartolomeu (Pyrus communis L.) have been used to produce a traditional product named “pêra passa de Viseu”. These pears are dried at direct open air sun exposure, following a multi-step procedure. However, this procedure does not comply with modern quality standards, and therefore in the last years some investigation around this product and the production method has been carried out to better understand it and establish alternative production techniques [2], [3]. Among these alternatives, a solar stove with forced convection and a solar stove with natural convection were developed. In the present work pears of the variety S. Bartolomeu were dried following the traditional method at direct solar exposure and also inside the two stoves developed. The chemical properties were analyzed and quantified in the pears dried by the 3 systems, having in mind to find out which system allows the obtaining of a product more similar to the traditional pears. From the results obtained is possible to see that the drying carried out inside the solar stoves dos not produce fruits much different than those dried by the traditional method.
- Comparative study of the drying kinetics of pears for different drying systems.Publication . Almeida, Inês; Guiné, Raquel; Lima, Maria João; Ferreira, DulcieniaOpen-air sun drying has been used since immemorial times to dry grains, vegetables, fruits and other agricultural products. This is a common method used to preserve foods and it is practiced until today in many countries where the combination of solar radiation, temperature and relative humidity is appropriate. However, despite being a cheap method, the open-air natural sun drying is not always applicable to large-scale production [1]. “Pera Passa de Viseu” denominates a traditional food product produced from pears of the variety S. Bartolomeu (Pyrus communis L.) using a traditional solar drying method, which is based on an open-air exposure [2]. Notwithstanding being quite a cheap drying method, making use of the sun as energy source, it has some very important disadvantages, like for example, the process is slow and very much dependent on weather conditions, and the quality of the product is not satisfactorily taking into account factors such as pollution from dust or from animal contamination or other types of infestation and microbial or mould contamination in humid environments. Therefore, the development of alternative drying methodologies assumes a pivotal role. The pears used in the present study were dried uncut after peeling, in three different systems: solar stove with forced convection, solar stove with natural convection and drying tunnel. The moisture content of the pulp was quantified along drying with a Halogen Moisture Analyzer. The objective of the present work is to fit the kinetic data to different models found in literature to describe the drying rates of food products, in order to compare the drying rates in the different systems tested and also to find out which model is best to describe the drying kinetics of these pears.
- Consumer Knowledge about Dietary Relevance of Fruits and Vegetables: A Study Involving Participants from Portugal and FrancePublication . Le Turc, Nolwenn; Silva, Ana Jaquelina; Florença, Sofia De Guiné E; Raposo, António; C. Goncalves, J.; Lima, Maria João; Teixeira de Lemos, Edite; Guiné, RaquelFruits and vegetables are recommended as low-calorie foods that contribute to the proper intake of necessary micronutrients, macronutrients, and bioactive compounds with health benefits. However, the recommendations for the dietary intake of these foods fail to be attained in most European countries. For this reason, promoting more knowledge about the health effects of fruits and vegetables is essential to decrease the incidence of chronic diseases. This study was conducted to investigate the knowledge of the health benefits of fruits and vegetables among the population of Portugal and France. The present work involved a questionnaire survey of 639 participants (257 from Portugal and 382 from France). The results revealed that most participants were young females (68.9%) with good education (76%) and an average weight range. They consumed a varied diet (57%) but had body dissatisfaction (63.2%). The respondents had good knowledge about the health effects of fruits and vegetables. However, the French population knew more about the theme than the Portuguese. Portuguese individuals were more likely to have incomplete information. Gender and education significantly influenced knowledge levels, with females and highly educated individuals demonstrating greater understanding. Dissatisfaction with body weight drives individuals to seek nutrition information. This investigation enhances our comprehension of the factors that affect knowledge of vegetable and fruit consumption among young adults in Portugal and France. Moreover, it highlights the importance of implementing focused educational programs to enhance nutrition literacy, particularly for less-aware demographic groups. Going forward, a more in-depth analysis of these factors could assist in creating more efficient strategies to encourage healthier dietary habits and improve nutrition literacy among these communities.
- Consumer study and sensorial evaluation of a newly developed spicy strawberry syrupPublication . Guiné, Raquel; Lima, Maria João; Pato, Lúcia; Correia, Ana Cristina; Gonçalves, Fernando; Costa, Elisa; Santos, SandraThe potential beneficial effects of strawberry allied to those of chilly in many aspects of human health lead to the development of a spicy strawberry syrup. The work included the development of the product, including formulation, processing and industrialization aspects, chemical and sensorial analyses as well as a consumer study, of which some will be analysed in the present manuscript. The sensorial evaluation was performed with a panel of 25 tasters, of which 17 were women and 8 men. The parameters evaluated using a hedonic scale were: visual aspect, colour, consistence, brightness, sweetness, strawberry taste, spicy taste, global appreciation. To characterization of the product a brief chemical analysis was made. The mineral content was determined by calcination at 550 ºC, the total soluble solids (mainly sugars) were determined by refractometry and the moisture by a halogen moisture analyser. In all characteristics evaluated in the sensorial analysis the medium punctuation was 4 (in a scale from 0 to 5), corresponding to Good. Despite the product being considered quite spicy, its acceptance was very good.
- Drying kinetics and mass transfer properties in the drying of thistle flowerPublication . Guiné, Raquel; Fontes, Luísa; Lima, Maria JoãoThistle flowers, and particularly their stigmas, are used to coagulate milk in the production of a number of traditional Portuguese cheeses due to their high milk-clotting activity provided by the high content of aspartic proteases. The aim of the present work was to determine the mass transfer properties of thistle flower under different drying conditions: natural drying and convective drying. Convective drying took place in a convection chamber set at different temperatures (35 to 65 °C) and the process was terminated when the sample presented a moisture content of about 5% or less. The traditional drying method was also used, placing the thistle flowers in a dry place sheltered from the sun, and leaving them to dehydrate at the variable room temperature. The present work allowed for the conclusion that convective drying was much faster than natural drying, and that the drying rate increased with temperature. The drying curve revealed an initial constant rate period followed by a falling rate. All the five thin layer models tested to fit the experimental data were shown to adequately describe the drying of the thistle flowers, but the best one was the Page model. The drying constant increased with temperature as did the effective diffusivity and the mass transfer coefficient. The results allowed one to estimate the activation energy for moisture diffusion (57 kJ/mol) and for convective mass transfer (78 kJ/mol). Thus this study showed the possibilities for designing efficient drying processes for the thistle flower used for milk-clotting in the manufacture of traditional cheeses.
- Drying kinetics and mass transfer properties for the drying of thistle flowerPublication . Guiné, Raquel; Fontes, Luísa; Lima, Maria JoãoBecause the drying of tistle flower is important due to its utilization as curd coagulant in Serra da Estrela cheese production, this work intended to study the drying process of thistle flower, by comparing the convective drying at constant tepetrature with the natural drying with variable temperature. For that, the natural drying process was monitored as to the evolvution of water loss along time and different experiments were conducted for the convenctive drying with air at 0.5 m/s at different tenperatures (between 35 and 65 ºC). The kinetic data were fitted to different thin layer models from literature and also to the Fick’s second law of diffusion. Also the mass transfer correlations were used to compute the mass trnafer properties. The results obtained indicated that the different thin layer models tested fitted wel the experimental data, with values of R between 0.972 and 0.999, but with slightly best results if using the Modified Page model (loest value of R equal to 0.997). The values of the moisture diffusion and mass transfer coefficients in all cases were found to increase with increasing temperature of the drying air, from 35 to 65 ºC. The values of diffusivity increased from 1.902x10-10 to 1.300x10-9 m2/s and the values of the mass transfer coefficient increased from 5.731x10-9 to 8.049x10-8 m/s. The values of activation energy for moisture diffusion and for mass transfer were found to be 56.48 kJ/mol and 77.66 kJ/mol, respectively.