DigitUMa

University of Madeira Institutional Repository

Bem-vindo ao Repositório Digital da UNIVERSIDADE DA MADEIRA.

O Repositório da Universidade da Madeira (UMa), conhecido pelo acrónimo DigitUMa, tem como objetivo a disponibilização, em regime de livre acesso e texto integral, de toda a produção científica realizada pelos docentes, investigadores da UMa, discentes dos 2º e 3º ciclos e pelos funcionários.

O Repositório Institucional, DigitUMa, assenta na política de Acesso Aberto à informação e conhecimento científicos.

Email antonio.freitas@staff.uma.pt

Recent Submissions

The fingerprint of fortified wines—From the sui generis production processes to the distinctive aroma

Publication . Perestrelo, Rosa; Jaouhari, Yassine; Abreu, Teresa; Castillo, Mariangie M.; Travaglia, Fabiano; Pereira, Jorge A. M.; Câmara, José S.; Bordiga, Matteo; Perestrelo, Rosa; Augusto Machado Pereira, Jorge; Câmara, José

The fortified wines that originated in Mediterranean countries have, in common, a high alcohol content to increase their shelf-life during long journeys to northern Europe and the American continent. Nowadays, the world’s better-known wines, including Marsala, Madeira, Port, and Sherry, due to their high alcoholic content, sweet taste, and intense aromatic profile, are designated as dessert wines and sometimes served as aperitifs. This review gives an overview of the traditional vinification process, including the microbiota and autochthonous yeast, as well as the regulatory aspects of the main Italian, Portuguese, and Spanish fortified wines. The winemaking process is essential to defining the volatile organic compounds (VOCs) that characterize the aroma of each fortified wine, giving them an organoleptic fingerprint and “terroir” characteristics. The various volatile and odorous compounds found in fortified wines during the oxidative aging are discussed in the last part of this review.

2023-06-30Journal article

Open access

Exploring the potential of microextraction in the survey of food fruits and vegetable safety

Publication . Berenguer, Cristina V.; García-Cansino, Laura; Ángeles García, María; Marina, María Luisa; Câmara, José S.; Pereira, Jorge A. M.; Câmara, José; Augusto Machado Pereira, Jorge

The increasing demand for food to feed an exponentially growing population, the fast evolution of climate changes, how global warming affects soil productivity, and the erosion of arable lands, create enormous pressure on the food chain. This problem is particularly evident for fresh fruits and vegetables that have a short shelf life. For this reason, food safety precautions are not always a priority and they are often overused to increase the productivity and shelf life of these food commodities, causing concerns among consumers and public authorities. In this context, this review discusses the potential of microextraction in comparison to conventional extraction approaches as a strategy to improve the survey of food safety requirements. Accordingly, selected examples reported in the literature in the last five years will focus on the detection and quantification of pesticides, antibiotics, hormones, and preservatives in fresh fruits and vegetables using different extraction approaches. Overall, the use of microextraction techniques to survey the presence of contaminants in the food chain is very advantageous, involving simpler and faster protocols, reduced amounts of solvents and samples, and consequently, reduced waste produced during analysis while conserving a high potential for automation. Additionally, this higher greener profile of the microextraction techniques will boost a progressive substitution of conventional extraction approaches by microextraction processes in most analytical applications, including the survey of food chain safety.

2023-06-14Journal article

Open access

Evaluation of tropane alkaloids in teas and herbal infusions: effect of brewing time and temperature on atropine and scopolamine content

Publication . González-Gómez, Lorena; Morante-Zarcero, Sonia; Pereira, Jorge A. M.; Câmara, José S.; Sierra, Isabel; Augusto Machado Pereira, Jorge; Câmara, José

Atropine and scopolamine belong to the tropane alkaloid (TA) family of natural toxins. They can contaminate teas and herbal teas and appear in infusions. Therefore, this study focused on analyzing atropine and scopolamine in 33 samples of tea and herbal tea infusions purchased in Spain and Portugal to determine the presence of these compounds in infusions brewed at 97 °C for 5 min. A rapid microextraction technique (µSPEed®) followed by high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) was used to analyze the selected TAs. The results showed that 64% of the analyzed samples were contaminated by one or both toxins. White and green teas were generally more contaminated than black and other herbal teas. Of the 21 contaminated samples, 15 had concentrations above the maximum limit for liquid herbal infusions (0.2 ng/mL) set by Commission Regulation (EU) 2021/1408. In addition, the effects of heating conditions (time and temperature) on atropine and scopolamine standards and naturally contaminated samples of white, green, and black teas were evaluated. The results showed that at the concentrations studied (0.2 and 4 ng/mL), there was no degradation in the standard solutions. Brewing with boiling water (decoction) for 5 and 10 min allowed for higher extraction of TAs from dry tea to infusion water.

2023-05-27Journal article

Open access

Differences in the volatilomic urinary biosignature of prostate cancer patients as a feasibility study for the detection of potential biomarkers

Publication . Riccio, Giulia; Berenguer, Cristina V.; Perestrelo, Rosa; Pereira, Ferdinando; Berenguer, Pedro; Ornelas, Cristina P.; Sousa, Ana Célia; Vital, João Aragão; Pinto, Maria do Carmo; Pereira, Jorge A. M.; Greco, Viviana; Câmara, José S.; Berenguer, Cristina; Perestrelo, Rosa; Augusto Machado Pereira, Jorge; Câmara, José

Prostate cancer (PCa) continues to be the second most common malignant tumour and the main cause of oncological death in men. Investigating endogenous volatile organic metabolites (VOMs) produced by various metabolic pathways is emerging as a novel, effective, and non-invasive source of information to establish the volatilomic biosignature of PCa. In this study, headspace solid-phase microextraction combined with gas chromatography–mass spectrometry (HS-SPME/GC-MS) was used to establish the urine volatilomic profile of PCa and identify VOMs that can discriminate between the two investigated groups. This non-invasive approach was applied to oncological patients (PCa group, n = 26) and cancer-free individuals (control group, n = 30), retrieving a total of 147 VOMs from various chemical families. This included terpenes, norisoprenoid, sesquiterpenes, phenolic, sulphur and furanic compounds, ketones, alcohols, esters, aldehydes, carboxylic acid, benzene and naphthalene derivatives, hydrocarbons, and heterocyclic hydrocarbons. The data matrix was subjected to multivariate analysis, namely partial least-squares discriminant analysis (PLS-DA). Accordingly, this analysis showed that the group under study presented different volatomic profiles and suggested potential PCa biomarkers. Nevertheless, a larger cohort of samples is required to boost the predictability and accuracy of the statistical models developed.

2023-05-10Journal article

Open access

Delving into agri-food waste composition for antibacterial phytochemicals

Publication . Pereira, Jorge A. M.; Berenguer, Cristina V.; Câmara, José S.

The overuse of antibiotics in the healthcare, veterinary, and agricultural industries has led to the development of antimicrobial resistance (AMR), resulting in significant economic losses worldwide and a growing healthcare problem that urgently needs to be solved. Plants produce a variety of secondary metabolites, making them an area of interest in the search for new phytochemicals to cope with AMR. A great part of agri-food waste is of plant origin, constituting a promising source of valuable compounds with different bioactivities, including those against antimicrobial resistance. Many types of phytochemicals, such as carotenoids, tocopherols, glucosinolates, and phenolic compounds, are widely present in plant by-products, such as citrus peels, tomato waste, and wine pomace. Unveiling these and other bioactive compounds is therefore very relevant and could be an important and sustainable form of agri-food waste valorisation, adding profit for local economies and mitigating the negative impact of these wastes’ decomposition on the environment. This review will focus on the potential of agri-food waste from a plant origin as a source of phytochemicals with antibacterial activity for global health benefits against AMR.

2023-05-07Journal article

Open access