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- Analysis of textural characteristics in bread prepared with incorporation of ewe’s wheyPublication . Guiné, RaquelBread is considered one of the basic foods consumed all over the world. Because the flours used for baking bread vary greatly in terms of chemical composition and also because of the differences in the baking processes used, breads constitute a group of food products with extremely heterogeneous structures, which in turn determine bread textural characteristics. The present trend to enrich breads with nutritional components has led to the utilization of residues from the food industry as a way to join the advantages of recuperation of beneficial compounds with the minimization of environmental impacts. The objective of this work was to develop new breads incorporating whey residue obtained from ewe’s milk after the production of Serra da Estrela Cheese. The developed products were analysed in terms of textural properties, and compared with a basic wheat bread also produced under similar conditions. To measure the textural properties, two types of test were performed (compression and puncture). The results indicated that the whey residue could be successfully used to produce bread with desirable textural properties, and this was particularly important for the improved formulation, which aimed to bring additional nutritional benefits to the consumer. The improved whey bread presented good textural characteristics, which remained practically unchanged after 24 h without any special type of container. This consistency in the textural properties was verified for all the properties evaluated: hardness, chewiness, resilience, cohesiveness, springiness evaluated by the compression test and external firmness, inner firmness, stickiness, adhesiveness evaluated by the puncture test. Furthermore, very strong correlations were found between some of textural properties, namely between cohesiveness and resilience and between adhesiveness and stickiness.
- Chemical and Physical Properties of Some Hazelnut Varieties Grown in PortugalPublication . Ferrão, Ana Cristina; Guiné, Raquel P. F.; Ramalhosa, Elsa; Lopes, Arminda; Rodrigues, Cláudia Filipa; Martins, Hugo; Gonçalves, Roberto; Correia, PaulaHazelnuts are one of the most appreciated nuts worldwide due to their unique organoleptic and nutritional characteristics. The present work intended to analyse several physical and chemical properties of different hazelnut varieties grown in Portugal, namely Tonda de Giffoni, Grada de Viseu, Segorbe, Longa de Espanha, Butler, Gunslebert, and Negreta. In general, the results revealed statistically significant differences between the varieties under study. The Gunslebert had more elongated hazelnuts and with heavier shelled fruits, while the kernels of the Grada de Viseu revealed to be heavier. Grada de Viseu was harder in the shell, Gunslebert had a harder core, and Segorbe was more resistant to fracture. Fat was the more representative component for all varieties and in some cases the values of moisture and water activity were over the recommended amount (≥0.62). Tonda de Giffoni was the variety with the highest induction time, indicating the highest oxidation stability. Moreover, discriminant analysis revealed that the variables more important to distinguish the varieties were protein (λ = 0.007) and water activity (λ = 0.010). The results of this study help to better understand the differences between some hazelnut varieties that are cultivated in Portugal, which gives important hints for all players in the hazelnut sector.
- Comparação entre as Propriedades das Peras Secadas sob Diferentes MétodosPublication . Guiné, Raquel; Barroca, Maria João; Lopes, Paulo; Silva, Vitor; Santos, Monica; Ferreira, DulcineiaNo primeiro ano de secagem das peras, 2007, teve-se por objectivo o estudo da secagem da pêra de S. Bartolomeu por dois métodos, secagem em estufa realizada na Escola Superior Agrária de Viseu e secagem em túnel realizada na Universidade de Coimbra. Este estudo foi efectuado para três estados de maturação diferentes visando o estabelecimento da melhor altura para a realização da colheita dos frutos. No ano de 2008 as pêras, de colheita única, foram secadas na ESAV, em estufa solar com aquecimento directo e ventilação forçada, na Universidade de Coimbra, em túnel com aquecimento solar indirecto e na Escola Superior de Tecnologia de Viseu, também em estufa solar com incidência directa da luz, e convecção natural. Da comparação verifica-se que as pêras secadas na ESAV e na ESTV (com incidência directa do sol) assemelham-se mais às tradicionais, enquanto as secadas na UC (sem incidência directa da luz solar) se apresentam com características distintas.
- Produção de farinha de larvas e pupas de zângãoPublication . Correia, Paula; Vouga, C.; Coelho, C.; Guiné, Raquel P. F.; Costa, Cristina Amaro DaA técnica da remoção dos quadros de zângão, utilizada no controlo do ácaro Varroa destructor, pode proporcionar uma fonte alternativa de alimento, sendo para isso necessário desenvolver técnicas simples e viáveis de extração e utilização das larvas e pupas. Este trabalho teve como objetivo testar dois métodos de extração, o método de extração a frio e a quente. Após a recolha os quadros foram congelados para garantir a sua conservação. Seguiu-se a extração das larvas e pupas através de métodos de extração a frio e extração quente (imersão em água a ferver). A extração a frio foi realizada manualmente com duas condições: sala fria (61ºC); superfície fria. Os rendimentos de extração variaram entre 62,57,5% e 84,94,0%, respetivamente para a superfície fria e para a extração a quente. Os tempos de extração mais elevado foi para a extração a frio em sala fria (336,342,4 segundos) e o mais baixo para a superfície fria (246,830,1 segundos). As larvas e pupas foram submetidas a dois tipos de desidratação: vaporização e liofilização. A vaporização escureceu demasiado as larvas e pupas não se revelando um bom processo de secagem. Deste modo, a farinha foi produzida a partir da trituração das larvas e pupas secadas por liofilização (até peso constante). Nutricionalmente as farinhas apresentaram-se ricas em proteína e gordura. Este novo produto poderá proporcionar o aumento do rendimento da atividade apícola, benefícios nutricionais e usos na produção de novos produtos à base de farinha de zângão.
- Is Better Knowledge about Health Benefits of Dietary Fiber Related to Food Labels Reading Habits? A Croatian OverviewPublication . Ljubičić, M.; Sarić, M. M.; Rumbak, I.; Barić, I. C.; Sarić, A.; Komes, D.; Šatalić, Z.; Dželalija, B.; Guiné, Raquel P. F.The aim of this cross-sectional study was to determine the associations between health dietary patterns, knowledge, and consumption of dietary fiber (DF) with frequency of food label reading on food products with special reference to DF. The study was conducted in 2536 Croatian adults using an original questionnaire. Multiple linear regression models were used to assess associations between food label reading habits and predictor variables. Our study confirms the association between habits regarding the reading of labels on food products, especially in relation to information about DF with the sociodemographic factors of respondents, dietary food patterns and DF consumption, as well as knowledge and sources of information about DF. Women, individuals with a university-level education, and those living in an urban environment had more frequent labels used. Food habits as well as eating outside of the home were positive predictors while eating fast food was a negative predictor of food label reading. Knowledge about DF, especially about its health benefits, was also associated with food label reading. The interpretation of associations could help with the design of effective public health programs. Targeted education campaigns to educate and sensitize the population about food labeling and monitoring may improve general knowledge about healthy food and its benefits, which include indirect effects on the prevention of non-communicable chronic diseases.
- Influence of food education in eating habits in students from 2nd and 3rd cycles in viseu schoolsPublication . Fernandes, Sofia; Cardoso, Ana Paula; Abrantes, José Luís; Ferreira, Manuela; Guiné, RaquelIntroduction: Food Education as a means of promoting a healthy diet is very important nowadays, given the problems identified in the eating habits of the young’s, resulting in public health problems. The intervention strategies haven’t proved to be very effective and therefore children and young students still reveal inadequate diets and sedentary lifestyles. Objectives: Verify the level of knowledge about food and habits of the students; Analyze how the information provided by educators is sufficient to promote a healthy diet; Understand if physical activity is being neglected at the expense of the use of new technologies in relation to the maintenance of healthy habits. Methods: This is an investigation of descriptive-correlational nature based on a questionnaire. The target population of this study was the students in Viseu schools. The sample consisted of students aged between 10 and 15 years from the 5th to the 9th levels. It was randomly selected among classes belonging to each level of education. The data collected was analyzed by SPSS, using the Descriptive and Inferential Statistics. Results: The majority of students revealed a deficient knowledge about the concept of healthy diet, and the recommended dosages for the main groups of foods. Furthermore, the evaluation of the eating habits of the students showed that sometimes they prefer foods that please, like chocolate or chips, for example in disfavor of foods that promote health, such as fruits, milk or soup. Conclusions: The food education is still a challenge and a major investment must be made on this area so as to promote health and minimize the important public health problems in future generations.
- Food product development: whey cheese with pumpkin jamPublication . Guiné, Raquel; Costa, Elisa; Santos, Sandra; Correia, Ana Cristina; Correia, Paula; Pato, LúciaIn Portugal a popular desert is whey cheese with pumpkin jam. However, these two products are only sold separately. Having in mind that the production of a combination of these two would be potentially interesting for new food commercializing, studies were conducted on the development of this new food product. A sensorial evaluation and a consumer study were conducted to perceive how consumers accepted this new product. The sensorial evaluation consisted of a descriptive analysis, with a panel of 17 tasters. The parameters evaluated using five points hedonic scales were: homogeneity in colour, homogeneity of the product, milk aroma, intensity of aroma, intensity of taste, salty taste, milk taste, sweetness, consistency and presence of granules. The results of the classification given to the different parameters evaluated in the sensorial analysis showed that only the salty taste received a classification of 2 (in a scale of 1 to 4), whereas all the others had 4 or 5, indicating that the panellists appreciated the product. Regarding the consumer study, this was performed by applying questionnaires to 100 persons. The results showed that almost 60 % of the enquired referred liking whey cheese with pumpkin jam. As to the frequency of consumption, the majority does it monthly, but there is still a good deal of people who do it daily. From the results obtained, it can be inferred that this product can be a successful innovation in the Portuguese dairy industry.
- Modeling the influence of production and storage conditions on the blueberry qualityPublication . Guiné, Raquel; Matos, Susana; Gonçalves, Christophe; Costa, Daniela Vasconcelos Teixeira da; Mendes, Mateus; Gonçalves, FernandoBlueberry is a widely consumed fruit with major economic value, appreciated due to its characteristic flavor as well as health benefits. The present work aimed to evaluate the effect of several production factors and storage conditions on some chemical and physical properties of blueberries. Some physical and chemical characteristics (moisture, acidity, sugars, color and texture) of blueberries from three cultivars, originating from five different locations and conventional or organic farming, were evaluated. The variation of the properties along time was also evaluated for storage at room temperature and refrigeration. Moreover, artificial neural network models were developed to estimate the physical-chemical characteristics of the blueberries, as influenced by the production and conservation factors considered. The results showed that all the characteristics considered varied according to cultivar, place of cultivation and production mode. The storage conditions also induced changes in the chemical components as well as in color and texture. The changes were dependent on type and duration of storage, cultivar and production mode. Weight analysis of the artificial neural network models highlighted the patterns and trends observed experimentally.
- Effect of Drying Temperature on the Physical-chemical and Sensorial Properties of Eggplant (Solanum melongena L.)Publication . Guiné, Raquel; Correia, Paula; Correia, Ana Cristina; Gonçalves, Fernando; Brito, Mariana; Ribeiro, JéssicaBackground: Eggplant is an important crop, being cultivated and consumed in many countries. However, like other vegetables, is highly perishable and has a short shelf life. Objective: The objective of this study was to evaluate the effect of hot air drying on some physical, chemical and sensorial properties of eggplant. Methods: Eggplant samples were dried in convective chambers at constant temperatures of 50, 60, 70 and 80°C. The fresh and dried samples were evaluated for moisture, water activity, vitamin C, total phenolic compounds, antioxidant activity, colour and texture. To complement the study, a sensorial evaluation was made by a consumer panel. Results: The results showed that drying decreased importantly the contents of vitamin C and phenolic compounds as well as antioxidant activity. Moreover, the negative impact was higher for higher drying temperatures. Drying also altered the colour, turning the samples darker. The textural properties were similarly considerably altered by drying, although the temperature did not show significant influence. Regarding the sensorial evaluation, even though it allowed establishing the sensory profiles of the dried samples, it was not possible to clearly distinguish among them, particularly the global appreciation. Conclusion: It was concluded that the drying operation substantially changed the physical, chemical and sensory properties of eggplant. Furthermore, the drying temperature had higher effect on the chemical components and colour and nor so much on the texture.
- 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.