CTT-UCVA

Background and Aims: Microbial contamination affects winemaking, especially after fermentation, e.g. wine ageing in barrels or in contact with oak pieces, when spoilage microbes find an environment favourable for their development. Ozone was evaluated as a sanitising agent in order to assess its potential to prevent microbial spoilage occurring during ageing of wine in barrels using a model system based on barrel wood. Methods and Results: Fifty microorganisms of oenological significance were evaluated for their spoilage potential in the barrel. Ethanol resistance, biofilm formation and production of volatile phenols were studied using physiological tests. The effectiveness of ozone in eliminating microorganisms was evaluated in aqueous solution at several cell and ozone concentrations. At a high cell concentration, the presence of organic matter reduced the effectiveness of ozone. At a cell concentration of under 10 3 CFU/mL, typical of wine cellars, ozone was able to eliminate microorganisms. Resistance to ozone was observed in diverse microorganisms, and this feature is linked to their ability to produce a biofilm. The reduction in simple phenols obtained from oak wood was tested by treating oak chips, routinely used in the wine industry, with an increasing dose of ozone. There was no statistical difference in the phenolic composition of wine treated with six commercial chips. Only a significant exposure of the chips to ozone caused a 33%reduction in the initial content of gentisic acid. Conclusions: Ozone was shown to be a highly effective sanitising agent without interfering with the profile of the phenolic substances extracted from oak. The application of ozone for barrel sanitising may be a feasible solution for the prevention of wine spoilage during ageing in oak barrels. Significance of the Study: A survey of the effect of ozone on a large number of microorganisms and phenolic compounds of oenological significance, considering some technological variables, is reported.

Silica-based material Solegel Solid state NMR Barrels Dekkera/Brettanomyces Wine spoilage a b s t r a c t The paper presents a new approach, covering wood with silica-based material in order to protect it from spoilage due to microbial colonisation and avoiding the loss of the natural features of the wood. Wood specimens derived from wine barrels were treated with methyltriethoxysilane in gas phase, leading to the deposition of a silica nanofilm on the surface. 29 Si and 13 C solid state Nuclear Magnetic Resonance and Scanning Electron MicroscopeeEnergy Dispersive X-ray analysis observations showed the formation of a silica polymeric film on the wood samples, directly bonding with the wood constituents. Inductively Coupled Plasma-Mass Spectroscopy quantification of Si showed a direct correlation between the treatment time and silica deposition on the surface of the wood. The silica-coated wood counteracted colonisation by the main wine spoilage microorganisms, without altering the migration from wood to wine of 21 simple phenols measured using a HPLC-Electrochemical Coulometric Detection.

Nostrano-cheeses" are traditional alpine cheeses made from raw cow's milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of "Nostrano-cheeses" and evaluated their potential to produce -aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters ( = 97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0 ± 2.7 mg/kg) was a Sc. thermophilus.

Polyamine content and activities of enzymes of polyamine biosynthesis were assayed during somatic embryogenesis in Vitis vinifera callus cultures of Chardonnay and Brachetto 'a grappolo lungo' (Brachetto g.l.) cultivars. The analyses were carried out on embryogenic callus samples, embryos at different stages and developing plants. Polyamine content, both in the free and PCA-soluble conjugated form, was higher in Brachetto g.l. than in Chardonnay, and putrescine was present at higher concentrations than the other polyamines. In all samples of both cultivars, ornithine decarboxylase activity (ODC, EC 4.1.1.17) was higher than arginine decarboxylase (ADC, EC 4.1.1.19), with a maximum in developing plant roots. S-Adenosylmethionine decarboxylase (SAMDC, EC 4.1.1.50) activity displayed a similar trend. The activities of all three enzymes were detected both in the supernatant and pellet fractions, indicating for the first time the presence of SAMDC activity in the particulate fraction. Particularly in the Chardonnay cultivar, an increase in the mRNAs expression patterns of ODC and SAMDC during morphogenesis from small embryos to plantlets was detected by northern blot, suggesting a direct correlation with enzymatic activities.

Silica-based material Solegel Solid state NMR Barrels Dekkera/Brettanomyces Wine spoilage a b s t r a c t The paper presents a new approach, covering wood with silica-based material in order to protect it from spoilage due to microbial colonisation and avoiding the loss of the natural features of the wood. Wood specimens derived from wine barrels were treated with methyltriethoxysilane in gas phase, leading to the deposition of a silica nanofilm on the surface. 29 Si and 13 C solid state Nuclear Magnetic Resonance and Scanning Electron MicroscopeeEnergy Dispersive X-ray analysis observations showed the formation of a silica polymeric film on the wood samples, directly bonding with the wood constituents. Inductively Coupled Plasma-Mass Spectroscopy quantification of Si showed a direct correlation between the treatment time and silica deposition on the surface of the wood. The silica-coated wood counteracted colonisation by the main wine spoilage microorganisms, without altering the migration from wood to wine of 21 simple phenols measured using a HPLC-Electrochemical Coulometric Detection.

The paper shows the isotopic ratios ( 13 C/ 12 C, D/H, 18 O/ 16 O) in oil and extracted glycerol and the mineral composition of authentic PDO and PGI Italian extra-virgin olive oils, officially collected from 2000 to 2005 (N = 539) to establish a national databank. 13 C/ 12 C and 18 O/ 16 O increased from Trentino to Sicily, each year distinguishing Northern Italy from Sicily and Calabria. Significant differences were found among the years and in some cases also between PDOs from the same region. 13 C/ 12 C and 18 O/ 16 O in bulk oil were significantly correlated with those in glycerol. D/H, measured in 2005 for the first time in oil, showed promising geographical discrimination capability. The content of 26 elements -Li, Rb, Cs, La, Ce and Yb rarely reported in the literature -was measured in well settled 2005 oils after ultrasound acid extraction.

Intensive methods of orchard cultivation require more effective ways of irrigation and fertilization. Recently apple (Malus ×domestica) orchards in the Trentino area of northeastern Italy have converted from traditional sprinkler irrigation to drip irrigation, both with or without fertigation. An experimental field trial was started at the end of 2008 in a 'Golden Delicious'/M9 orchard at Tres (Province of Trento) to develop specific fertilization plans, in order to limit fertilizer input and reduce nutrient runoff into waterways. A factorial experiment with two fertilizer treatments (soil application of granular fertilizers or fertigation through drip emitters) and two water application rates (1500 or 3000 m 3 /ha/yr) was established. Compared with granular fertilizer, fertigation significantly increased leaf greenness, increased leaf nitrogen (N) concentration, and reduced phosphorus (P) concentration in the fruits at harvest. The Normalized Difference Vegetation Index (ND...

Selection of resistant rootstocks to overcome recent climate-change events is a crucial factor for developing sustainable agricultural practices and for assuring optimal quality of grapes. Our study examined responses of four new rootstocks selected for resistance to water and salt stresses, iron chlorosis, vigor reduction, and enhanced potassium (K) and magnesium (Mg) uptake efficiency. The new rootstocks are the result of crossing various species of Vitis (riparia, cordifolia, rupestris and berlandieri) alone or in combination. The four new genotypes were compared with six conventional rootstocks grown at five locations in Italy, using the same 'Cabernet Sauvignon' scion and similar management practices. This paper reports the 2011 data for leaf SPAD and NDVI values, and K, Mg, calcium (Ca), iron (Fe) and boron (B) concentrations both in leaves and in petioles sampled at veraison. INTRODUCTION In response to climatic changes over the past few decades, the Dipartimento Prod...