SIMULATION OF THE TEMPERATURE PROFILE OF A PECTIN SOLUTION IN A PLATE HEAT EXCHANGER: A NON-LINEAR SYSTEM APPROACH FOR CONTROL

Experimental measurement can be made only of inlet and outlet global temperature of plate heat exchanger (PHE), therefore the temperature profile along of a PHE is hardly ever known. The goal of this work was to evaluate the influence of a non-Newtonian behavior of pectin solution in the temperature response curves along of the PHE. The results were obtained using a simulation codified in Matlab 6.1 software. The response curves resulted from the simulations were fitted to models for identification and characterization of the system linearity. The result shows a clear non-linear behavior of the response curves along the PHE

Altura e diâmetro de plantas de um clone de eucalipto e produção de massa seca de P. maximum cv. Massai na integração lavoura-pecuária-floresta.

O objetivo neste trabalho foi avaliar a altura e diâmetro de plantas de eucalipto e a produção de massa seca do P. maximum cv. Massai (capim-massai) e sorgo forrageiro BRS800 cultivados em SILPF no estágio inicial de implantação do sistema

Sensory profile, shelf life, and dynamics of bioactive compounds during cold storage of 17 edible flowers

In this study, 17 edible flowers (Allium ursinum L., Borago officinalis L., Calendula officinalis L., Centaurea cyanus L., Cichorium intybus L., Dianthus carthusianorum L., Lavandula angustifolia Mill., Leucanthemum vulgare (Vaill.) Lam., Paeonia officinalis L., Primula veris L., Robinia pseudoacacia L., Rosa canina L., Rosa pendulina L., Salvia pratensis L., Sambucus nigra L., Taraxacum officinale Weber, and Tropaeolum majus L.) were investigated to assess their sensory profile at harvest and their shelf life and bioactive compounds dynamics during cold storage. The emerging market of edible flowers lacks this information; thus, the characteristics and requirements of different flower species were provided. In detail, a quantitative descriptive analysis was performed by trained panelists at flower harvest, evaluating 10 sensory descriptors (intensity of sweet, sour, bitter, salt, smell, specific flower aroma, and herbaceous aroma; spiciness, chewiness, and astringency). Flower visual quality, biologically active compounds content (total polyphenols and anthocyanins), and antioxidant activity (FRAP, DPPH, and ABTS assays) were evaluated both at harvest and during storage at 4 °C for 14 days to assess their shelf life. Generally, species had a wide range of peculiar sensory and phytochemical characteristics at harvest, as well as shelf life and bioactive compounds dynamics during postharvest. A strong aroma was indicated for A. ursinum, D. carthusianorum, L. angustifolia, and L. vulgare, while B. officinalis and C. officinalis had very low values for all aroma and taste descriptors, resulting in poor sensory profiles. At harvest, P. officinalis, R. canina, and R. pendulina exhibited the highest values of polyphenols (884–1271 mg of gallic acid equivalents per 100 g) and antioxidant activity (204–274 mmol Fe2+/kg for FRAP, 132–232 and 43–58 µmol of Trolox equivalent per g for DPPH and ABTS). The species with the longest shelf life in terms of acceptable visual quality was R. pendulina (14 days), followed by R. canina (10 days). All the other species lasted seven days, except for C. intybus and T. officinale that did not reach day 3. During cold storage, the content of bioactive compounds differed, as total phenolics followed a different trend according to the species and anthocyanins remained almost unaltered for 14 days. Considering antioxidant activity, ABTS values were the least variable, varying in only four species (A. ursinum, D. carthusianorum, L. angustifolia, and P. officinalis), while both DPPH and FRAP values varied in eight species. Taken together, the knowledge of sensory profiles, phytochemical characteristics and shelf life can provide information to select suitable species for the emerging edible flower market