221 documents found, page 1 of 23
Looking for the optimal harvest time of red grapes with an enzymatic electroche...
Garcia-Hernandez, Celia; Perez-Gonzalez, Clara; Martin-Pedrosa, Fernando; Dias, L.G.; Barajas-Tola, E.; Rodriguez-Mendez, M.L.; Garcia-Cabezon, CristinaThe timing of the grape harvest is a critical decision for winemakers, as it greatly impacts the quality and organoleptic characteristics of the resulting red wines. One key indicator for determining the optimal harvest time is the phenolic content of the grapes. As the berries ripen, phenolic compounds in the grape skin cells migrate from the seeds to the pulp and finally to the skin. However, monitoring these...
Analysis of milk adulteration by means of a potentiometric electronic tongue
Perez-Gonzalez, Clara; Garcia-Hernandez, Celia; Garcia-Cabezon, Cristina; Rodriguez-Mendez, M.L.; Dias, L.G.; Martin-Pedrosa, FernandoMilk adulteration presents substantial challenges in the food industry, prompting the need for efficient de- tection methods. This study introduces a potentiometric electronic tongue for rapid and accurate detection of milk adulteration. Using polymeric membranes with various integrated additives, the electronic tongue distinguished between different milk types and detected common adul- terants. Experimental re...
Microbiological and Physicochemical Evaluation of Hydroxypropyl Methylcellulose...
Paula, Vanessa B.; Dias, L.G.; Estevinho, Leticia M.Dairy products are highly susceptible to contamination from microorganisms. This study aimed to evaluate the efficacy of hydroxypropyl methylcellulose (HPMC) and propolis film as protective coatings for cheese. For this, microbiological analyses were carried out over the cheese' ripening period, focusing on total mesophilic bacteria, yeasts and moulds, lactic acid bacteria, total coliforms, Escherichia coli, an...
Phenolic Class Analysis in Honey: Comparison of Classical and Single UV Spectru...
Paula, Vanessa B.; Sousa-Dias, Miguel L.; Seixas, Natália da Assunção Lisboa; Combarros-Fuertes, Patricia; Estevinho, Leticia M.; Dias, L.G.The analytical results from a study of 16 honey samples (extra white to dark honey color range) of phenolic compounds obtained using the single UV spectrum methodology and classical spectrophotometric methods (Folin–Ciocalteu and AlCl3 methods) are presented. The first method quantified all classes of phenolic compounds in honey’s SPE-C18 extract: the total hydroxybenzoic acid content (concentrations between 0....
Optimization of Extraction Method of Bioactive Compounds from Elderberries (Sam...
Pascariu, Oana-Elena; Dias, L.G.; Israel-Roming, FlorentinaPhenolic compounds from elderberries (Sambucus nigra L.) have attracted attention due to their potential health benefits. This paper examines different extraction methods used to obtain phenolic compounds from these fruits and the stability of the extracts. Several extraction techniques (extraction with continuous agitation, ultrasound-assisted extraction, microwave-assisted extraction, maceration, and enzyme-a...
Contribution to Characterizing the Meat Quality of Protected Designation of Ori...
Vasconcelos, Lia; Dias, L.G.; Leite, Ana; Pereira, Etelvina; Silva, Severiano; Ferreira, Iasmin; Mateo, Javier; Rodrigues, Sandra; Teixeira, AlfredoThe aims of this study were to describe and compare the meat quality characteristics of male and female kids from the "Serrana" and "Preta de Montesinho" breeds certified as "Cabrito Transmontano" and reinforce the performance of near-infrared reflectance (NIR) spectra in predicting these quality characteristics and discriminating among breeds. Samples of Longissimus thoracis (n = 32; sixteen per breed; eight m...
Fermented Grapevine Leaves: Potential Preserving Agent in Yogurt
Freitas, Lais; Sousa-Dias, Miguel L.; Paula, Vanessa B.; Dias, L.G.; Estevinho, Leticia M.In this study, we monitored the fermentative process of Vitis vinifera L. leaves (grapevine), spontaneously or promoted by Saccharomyces cerevisiae, in both solid and liquid media. We also aimed to evaluate the effect on the bioactivity and shelf life of yogurt incorporating fermented and non-fermented grapevine leaves compared to yogurt produced with the preservative potassium sorbate. The results revealed tha...
Can near-infrared spectroscopy replace a panel of tasters in sensory analysis o...
Vasconcelos, Lia; Dias, L.G.; Leite, Ana; Ferreira, Iasmin da Silva; Pereira, Etelvina; Bona, Evandro; Mateo, Javier; Rodrigues, SandraThis study involved a comprehensive examination of sensory attributes in dry-cured Bísaro loins, including odor, androsterone, scatol, lean color, fat color, hardness, juiciness, chewiness, flavor intensity and flavor persistence. An analysis of 40 samples revealed a wide variation in these attributes, ensuring a robust margin for multivariate calibration purposes. The respective near-infrared (NIR) spectra unv...
Comparative methods to evaluate the antioxidant capacity of propolis: an attemp...
Paula, Vanessa B.; Estevinho, Leticia M.; Cardoso, Susana M.; Dias, L.G.Propolis is a natural product produced by bees that contains a complex mixture of compounds, including phenolic compounds and flavonoids. These compounds contribute to its biological activities, such as antioxidant capacity. This study analysed the pollen profile, total phenolic content (TPC), antioxidant properties, and phenolic compound profile of four propolis samples from Portugal. The total phenolic compou...
Melipona scutellaris geopropolis: chemical composition and bioactivity
Coutinho, Sónia; Matos, Vanessa; Seixas, Natália da Assunção Lisboa; Rodrigues, Hellen; Paula, Vanessa B.; Freitas, Lais; Dias, TeresaGeopropolis has been used in traditional medicine for centuries. In this study, the botanical origin, physicochemical profile, and biological activities of geopropolis from Melipona scutellaris harvested during rainy and dry seasons were investigated. Palynological analysis identified over 50 pollen types, with Schinus terebinthifolius and Cecropia being the predominant types. The analytical results were in lin...