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- Flores comestíveis como fonte de compostos bioativos com atividade antioxidantePublication . Guiné, Raquel P. F.; Ferrão, Ana Cristina; Correia, Paula; Goncalves, J. C.; Gonçalves, Fernando JorgeExistem muitas espécies vegetais utilizadas na gastronomia, entre as quais as flores comestíveis (FC). Para que uma flor seja considerada comestível ela deve ser não tóxica, inócua e ter propriedades nutricionais. Historicamente, as FC têm sido usadas para fins culinários há séculos em várias partes do mundo, como Ásia, Grécia antiga, Roma e também na França medieval. Adicionalmente, constituem uma boa fonte de compostos bioativos, nomeadamente fitoquímicos, associados a várias propriedades farmacológicas, destacando a proteção contra doenças cardiovasculares e os efeitos ansiolíticos, anticancerígenos, antidiabéticos, anti-inflamatórios, antioxidantes, diuréticos, imunomoduladores e antimicrobianos. Recentemente, as FC têm despertado crescente interesse, devido às suas propriedades estéticas e organoléticas, bem como potenciais benefícios para a saúde, relacionados com a ocorrência de alguns compostos bioativos. Nesta medida, o objetivo do presente trabalho foi avaliar os teores de compostos fenólicos totais, antocianinas e flavonoides, bem como a atividade antioxidante num conjunto de FC. Para a análise foram obtidos extratos de onze espécies de FC que foram utilizados para a quantificação da composição fenólica e atividade antioxidante usando métodos espectrofotométricos. Dos resultados obtidos foi possível verificar que as rosas e cravos de coloração vermelha ou rosa se destacaram como contendo maiores teores de compostos fenólicos totais (18 a 27 mg EGA/g), e ainda maiores aportes de antocianinas (3 a 5 mg EC/g). Verificou-se ainda que eram também essas as FC com maior atividade antioxidante (12 a 16 mg ET/g). De destacar por fim o cravo vermelho como contendo maior quantidade de flavonoides (cerca de 18 mg EC/g). Em conclusão, verifica-se que as FC, para além das suas potencialidades gastronómicas, podem constituir um veículo para a ingestão de compostos com efeitos benéficos para a saúde, nomeadamente no que respeita ao combate aos radicais lives responsáveis pelo envelhecimento celular.
- Food safety in portuguese Companies in Covid-19 Pandemic ContextPublication . C. Goncalves, J.; Guiné, Raquel P. F.; Correia, Paula; Tomasevic, I.; Djekic, I.
- Flour from drone broods: A viable alternative?Publication . Correia, Paula; Vouga, C; Coelho, Catarina; Costa, Cristina Amaro Da; Guiné, Raquel P. F.; Gonçalves, Fernando Jorge; C. Goncalves, J.
- Insect flour as milk protein substitute in fermented dairy productsPublication . Neves, Vítor; Campos, Lara; Ribeiro, Nuno; Costa, Rui; Correia, Paula; C. Goncalves, J.; Henriques, MartaFermented dairy products (FDP) are consumed worldwide, due to their nutritional attributes and sensory properties. In the last decade, edible insects have been the subject of research as a sustainable source of protein to be introduced into the food industry. This study aims to demonstrate the effectiveness of black soldier fly (BSF) and drone brood (DB) flours in FDP, with or without probiotics, as a viable substitute of milk powder during refrigerated storage for 21 days. The nutritional composition of the products remained unchanged despite the addition of insect flour, with a fat content of ~0.95% and a protein content of ~4.7%. The products acidity increased from 0.78 to 1.06% lactic acid during storage. The colour of the FDP was typical yellowish-white, except for those containing BSF flour which had a darker colour. For all FDP, syneresis values were below 10% after the first day of storage, particularly for those with DB flour with syneresis as low as 5%. The probiotics had the highest values of Lactobacillus spp. (>6 log CFU/g) and Streptococcus spp. (>10 log CFU/g). The addition of the BSF flour was found to have a negative impact in the consumers’ perception of the products, according to the sensory analysis.
- Characteristics of enrichment of fresh pasta with bee drone broods flourPublication . Correia, Paula; Teixeira, G; Silva, A; Guiné, Raquel P. F.; Moitinho, A; Pitacas, I; C. Goncalves, J.Background: The fortification of staple food is one of the goals of modern technologies. Aim: In this study, preparation of pasta replacing wheat semolina flour with drone brood flours, rich in protein (27-38%), was tested. Method: The drone brood flour (DF) was obtained by the cold (CE) and hot (HE) extraction processes. After several trials, it was possible to incorporate 10% DFCE, and 20% DFHE. Pastas were evaluated in terms of its technological characteristics (optimum cooking time, cooking losses, swelling index), physical characteristics (colour and texture), chemical characteristics (nutritional composition) and sensory characteristics, and compared with a control pasta (0% dwarf flour). Results and discussion: The addition of DF increased the optimum cooking time, cooking loss and swelling index. The water absorption increased in the case of 10% DFCE pasta. The incorporation of DFCE caused a darker final product, however the incorporation of DFCE resulted in a slightly lighter product when compared to the control sample. In general, the addition of DF led to an increase in the hardness of pastas, particularly in the 20% DFHE samples. Moreover, pasta with added DF had a higher protein and ash content, thus increasing its nutritional quality. Sensorially, the DF pastas had an overall appreciation and a preferential purchase intention by the tasters, standing out in terms of the intensity of colour and aroma compared to the control pasta. Conclusion: DF is a promising ingredient in pasta production, contributing to human health and at the same time promoting economic returns.
- Production and characterization of powder from drone brood of honeybees (Apis mellifera)Publication . Goncalves, J. C.; Vouga, Beatriz; Costa, Cristina Amaro Da; Gonçalves, Fernando Jorge; Coelho, Catarina; Guiné, Raquel; Correia, PaulaDrone bee brood are a natural source of food with potential for human nutrition. This work aims to investigate the production and extraction of the drone bee brood (larvae and pupae), as well as the production of powder from this insect for food applications. To produce the drone brood (DB), in some hives of the colony appropriate empty frames were placed. Some measurements were done in the hive to monitor the global wellbeing of the colony, namely, temperature, relative humidity, and weight. After approximately one month, the frames were removed from the hives and frozen. The yield of DB by frame was 38%. For the extraction of the drone brood, different methods were tested, being the best ones the cold room extraction (∼ 6.5 °C), on a cold surface extraction (∼ 11 °C), and in boiling water extraction (100 °C). The results show that the extraction efficiencies were 74.3% (336.3 s), 62.5% (246.8 s) and 84.9% (332.0 s), for extraction in a cold room, on a cold surface, and in boiling water, respectively. After extraction, two drying processes were tested: evaporation and freeze-drying, being the last one the recommended, preserving in a better way the appearance and composition of the DB. DB powders presented different colour characteristics according to the extraction method used. The powder obtained by boiling extraction was darker than the one produced with cold extraction. Powders are rich in protein, fat and carbohydrates, being the fat content quite high for DB powders produced by boiling extraction method.
- Customer knowledge and behavior on the use of food refrigerated display cabinets: A Portuguese casePublication . C. Goncalves, J.; Guiné, Raquel P. F.; Amoedo, C.; Correia, PaulaThis article presents a study on customer knowledge and habits regarding the use of refrigerated display cabinets (RDC). The study was carried out on a sample of Portuguese retail stores’ customers, using a questionnaire survey available through an Internet platform. The sample consisted of 136 individuals, who voluntarily participated in the study. Questions included the characterization of the sociodemographic population involved. The questionnaire included different questions to related with RDC, namely customer knowledge about the appearance of each RDC equipment, questions to evaluate the respondents’ perception about the advantages and disadvantages related to open or glass-door closed RDC, questions to assess the participants’ habits and behavior when purchasing food products from glass-door closed RDC (frequency and duration of door open), questions to characterize the consumers’ habits on purchasing food products from RDC, and also questions to characterize the consumers’ shopping attitudes in the context of the COVID-19 pandemic, caused by SARS-CoV-2. The results seem to indicate that customers prefer closed RDC; for example, 61.8% of participants prefer products preserved in glass-door closed RDC, against 6.6% that admit to preferring products preserved in open RDC. Therefore, we can deduce that the existence of doors does not appear to be an obstacle to purchasing food products. Regarding the use of glass-door closed RDC, 80.1% of the participants say they just open the door once, and 53.7% of the costumers believe they keep the door open in the interval [4‒6 s]. This indicates that Portuguese customers are quite well informed about food safety issues and seem to follow assertive attitudes when purchasing food products from RDC. This study reinforces the benefits of replacing open RDC by closed glass-doors allowing significant energy savings.
- Evaluation of phenolic compounds and antioxidant activity in some edible flowersPublication . Gonçalves, Fernando Jorge; C. Goncalves, J.; Ferrão, Ana Cristina; Correia, Paula; Guiné, RaquelRecently, edible fl owers ( EF ) have aroused increased interest because of their aesthetic properties as well as potential health bene fi ts related to the occurrence of some bioactive compounds. Therefore, the aim of this work was to evaluate the total phenolics, anthocyanins, fl avonoids, and antioxidant activity ( AOA ) ( following DPPH and ABTS methods ) in eleven EF. The samples were subjected to three successive extraction steps using methanol, and these extracts were then analysed for the aforementioned properties using spectrophotometric methods. The obtained extracts were used for the quantification of phenolic composition and AOA. The results indicated that, among the fl owers analysed in this study, red rose, pink rose, and red carnation possessed the highest total phenolic contents ( 27.53, 23.30, and 18.17 mg g − 1 gallic acid equivalents, respectively ) , total anthocyanins ( 3.07, 1.97, and 4.47 mg g − 1 catechin equivalents [ CE ] , respectively ) , and AOA ( 12.07, 15.77, and 12.93 mg g − 1 TE, respectively, as given by the DPPH method or 8.23, 9.27 and 8.00 mg g − 1 TE, respectively, as given by the ABTS method ) . The flowers with highest fl avonoids contents were red carnation, Mexican marigold, and pink rose ( 17.50, 16.90, and 16.57 mg g − 1 CE, respectively ) . Cluster analysis grouped the analysed flowers into two groups, those richest in phenolics with AOA and those not so rich. Finally, some important correlations were observed between the total phenolics and the AOA. In conclusion, these fl owers could represent a potential source of natural compounds with antioxidant capacity.