Characterization and differentiation of sherry brandies using their aromatic profile

Aroma compounds of 48 Sherry brandies have been identified and quantified by the stir bar sorptive extraction method coupled to gas chromatography-mass spectrometry (SBSE-GC/MS). Analysis of variance and multivariate analysis techniques have been used to classify these brandy samples according to the commercial category (Solera brandy, Solera Reserva brandy, and Solera Gran Reserva brandy). From an univariate point of view (analysis of variance), several of the volatile compounds considered showed significant differences. Principal component analysis, using the global data matrix, showed that only the Solera brandy samples, with the shortest aging in wood, were well-differentiated from the others. Partial least-squares discriminant analysis (PLS-DA) results provided evidence of the ability of the content of volatile compounds to discriminate among the different commercial categories. Linear discriminate analysis allowed for a 93% differentiation according to the commercial category and, thus, the length of its aging process in wood. The results obtained show that it would be possible to ensure the commercial category of a Sherry brandy using its content of volatile compounds.     

Sugar contents of Brandy de Jerez during its aging

Brandy de Jerez is aged in American oak casks according to the traditional dynamic system (Soleras y Criaderas) and sometimes additionally by the static system (Anadas). The experimental arrangement used here for the analytical monitoring of brandy aging consisted of 15 casks, 12 of which were set up for aging by the dynamic system, which is well established in the denomination of origin area, whereas the other 3 contained the same brandy but aged according to the static system. This paper studies the kinetics of sugar extraction from oak wood to distillate, as well as the possible correlations between the sugar contents in brandy and its age or the commercial type it belongs to (Solera, Solera Reserva, or Solera Gran Reserva). High-performance anion-exchange chromatography with pulsed amperometric detection was used as the analytical tool to measure the concentrations of glucose, fructose, arabinose, galactose, and xylose, the presence of which in brandy has previously been described.     

Drought, salinity and heat differently affect seed germination of Pinus pinea

Drought, salinity and forest fires are adverse abiotic factors responsible for the failure of plant regeneration in the Mediterranean regions. The objective of this study was to evaluate Pinus pinea seed germination in response to heat, osmotic and salinity stress. Separate experiments were conducted, using polyethylene glycol (PEG) as an osmotic agent to reproduce drought stress, and sodium chloride (NaCl) and diluted seawater as salinizing agents to simulate salinity stress. Different temperatures were used to reproduce the effects of different fire regimes. Seed germination and the activities of the main enzymes involved in Pinus seed reserve utilization (glyoxylate cycle enzymes) decreased with increasing PEG, NaCl and seawater concentrations. Seawater appears to be the least toxic salinizing agent on Pinus pinea seed germination. The present study indicates that the germination of Pinus pinea seeds is influenced by the concentrations and even more by the nature and interactions of the ions present in the solutions. As regard heat treatments, the maximum germination percentage (80%) was obtained at 80°C and short exposure time (3 min). Increasing exposure time and temperature led to the germination percentage progressively decreasing.     

Extracellular protease production of bacteriolytic bacteria isolated from marine environments

ABSTRACT:   Fourteen bacterial strains isolated from marine environments exhibited antagonistic action against a wide range of bacteria including Vibrio spp. A double layer agar method was used for preliminary screening to determine the relative degree of growth inhibition or bacteriolysis exhibited by the isolates. Most of the antagonistic isolates were found to be Gram-negative, motile rods and were oxidase positive, and oxidative in the oxidation and fermentation test, suggesting that they are belong to the genera Pseudomonas . The antagonistic isolates lyzed the dead cells of marine Gram-negative bacteria in both plate and liquid methods. Bacteriolytic and casein hydrolytic activities were observed in the culture supernatant of the isolates. Anion exchange column chromatography (Toyopearl DEAE-650 M) was used to purify the extracellular protease produced by an antagonistic strain A1-J25a. The active fractions of protease collected from the eluted solution also exhibited bacteriolytic activity.     

Comparison of the evolution of low molecular weight phenolic compounds in typical Sherry wines: Fino,Amontillado, and Oloroso

Changes in the content of low molecular weight phenolic compounds (hydroxybenzoic and hydroxycinnamic acids, aldehydes, and their esterified derivatives, tyrosol and 5-(hydroxymethyl)-2-furaldehyde) during the aging of three different classes of Sherry wine, Fino, Oloroso, and Amontillado, have been studied. The samples studied were taken from each of the scales of the particular aging system applied to the three classes of wine. Clear differences were observed in the behavior of the low molecular weight phenolic in the three classes of wine. The wines subjected to oxidative aging presented a higher phenolic content overall, with the exception of the esterified derivatives of phenolic compounds that are mainly found in the samples that have not undergone any process of oxidation. MANOVA results confirmed that there are significant differences between all of the samples of the three types of wines. Using LDA, a classification of 100% of the samples has been made.     

Abundance,activity and critical habitat of the striped dolphin Stenella coeruleoalba in the Gulf of Taranto (northern Ionian Sea,central Mediterranean Sea)

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Effects of different thinning intensities on soil carbon storage in <Emphasis Type="Italic">Pinus laricio</Emphasis> forest of Apennine South Italy

This study investigated, in a Pinus laricio forest of south Italy, how systematic thinning of different intensities (intense thinning, T45; moderate thinning, T25; clear cut, CC; and no thinning, T0) affected soil biological properties, organic matter trend and carbon (C) storage in soil and plants. Soil carbon content and carbon/nitrogen (C/N) ratio were significantly higher in the T45 than in control, T25 and CC. Under T45, the soils had also the highest enzymatic activities, microbial biomass carbon (MBC) and colonies of fungi and bacteria. The humification parameters (humification ratio, HR; the degree of humification, DH; humification index, HI) indicated T45 as the best silvicultural practice-approach method to manage Pinus laricio forest for increasing soil carbon storage. The dendrometric parameters evidenced that T45 caused the greatest increment in wood growth (diameter and height), showing that the positive effect of the intense systematic thinning (T45) on the mechanical stability of plantation was related to the ability of trees to accumulate large amounts of carbon in their wood tissues. These data were confirmed by wood density value that was the highest in pine trees under the T45. This study showed that in Pinus laricio forest under T45 C stock increased in soil and plant, already 4 years after thinning.