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Syrah grapes harvested during the 2017 crop season in a biodynamic farm located in a hillside area around Lucca (Tuscany) were processed following a whole bunch winemaking, and the results were compared with those obtained by a traditional destemming winemaking in order to explore the potential quality of this kind of grape. With the aim to verify the impact of co-fermentation of intact grape clusters and stalk, both chemical and sensory profiles of wines were discussed soon after racking off as well as after 10 moths of ageing, and particular attention was paid to phenolic and aromatic compounds. Our results show that co-fermentation of intact grape clusters and stalk can be profitably applied in order to improve the nutraceutical features of Syrah wines as well as to emphasize their aromatic expression, thus allowing to significantly speed up their ageing phase. [ABSTRACT FROM AUTHOR]

This study involved the region of DOCG Cesanese del Piglio (Lazio), an area renowned for the cultivation of Cesanese d'Affile, which is an autochtonous variety of grape. To evaluate the effect induced by the addition of a cryogen (CO2,S) on the extraction of phenolic compounds, Cesanese d'Affile grapes coming from the same vineyard were transformed utilising the same winemaking technology, differing only for the stage of grape maceration. Main chemical parameters of the wines and their sensory profiles were analysed during winemaking and after 8 months of aging in oak barrels to observe the impact of cryomaceration on overall wine quality. It can be stated that the addition of a cryogen to the crushed grapes can be a viable choice to improve the expression of the main features of a native grape such as Cesanese d'Affile, preserving its nutraceutical features and giving to the product a more complex sensory profile. [ABSTRACT FROM AUTHOR]

Enzymatic preparations containing β-glucanases are largely utilised in winemaking to facilitate the filtration of musts and wines coming from grapes affected by Botrytis cinerea, and to induce the release of mannoproteins and oligosaccharides from the cell wall of yeasts. The aim of the present work was to investigate the effect of temperature on β-glucanase activity. For this purpose, the kinetic activity of a commercial enzymatic preparation containing β-glucanases was tested utilising a model solution (buffer solution of β-glucan extracted from alcoholic yeasts with a pH similar to a must/wine, with or without 13% ethanol added) at different temperatures ranging from 20 to 40°C. By an innovative procedure based on a kinetic model able to describe the time evolution of D-glucose accumulation -- the final product of β-glucan hydrolysis -- it was possible to relate the maximum rate of this process to temperature. The temperature at which the enzymatic activity showed the maximum value (Tmax) was close to 30°C, without any substantial variation following ethanol addition. Indeed, in spite of a remarkable reduction (of about 66%) in the catalytic activity shown by the commercial enzymatic preparation, no significant variation of the Tmax was observed, suggesting that the presence of an inhibitor such as ethanol in the reaction medium did not change the sensibility of the enzymes to temperature. [ABSTRACT FROM AUTHOR]

A mathematical model describing the evolution of aerobic and anaerobic respiration of Golden Delicious apples stored in refrigerated and controlled atmosphere, as a function of temperature, PO2 and PCO2 is presented and discussed. This paper reports: the hypothesis utilised to formulate the model; the kinetic equations used; the identification of the best values to be assigned to the functional parameters of the mathematical equations introduced; the model validation carried out by using an independent experimental data set. Despite the low number of functional parameters utilised, this model appears able to suitably describe the evolution of aerobic respiration and alcoholic fermentation rates of Golden Delicious apples stored at different temperatures, PO2 and PCO2. [ABSTRACT FROM AUTHOR]

The maceration of the solid parts (dregs) of grapes is a fundamental step of wine-making not only for the production of high quality red wines but also of structured white wines characterized by a high content of aromatic compounds. A mathematical model able to describe the time evolution of the phenolic fractions during grape maceration is reported and discussed. While the accumulation of total phenols and catechins in the must/wine during grape maceration can be described by the mass transfer equation introduced by Fick to evaluate the diffusion occurring between two heterogeneous phases, a more complex mathematical approach is introduced to determine the time evolution of anthocyanins. The extraction rate of different phenolic compounds, does not seem to vary significantly with the kind of fermentor or the wine-making technology used, but both the yield and chemical composition of the extracts appear to be significantly affected by extraction time. [ABSTRACT FROM AUTHOR]

In the cellar, slow and stuck fermentations occurring during winemaking are often successfully solved by the addition of yeast strains like Saccharomyces bayanus. The kinetic behaviour shown by S. bayanus during alcoholic fermentation was investigated using a mathematical model previously tested for S. cerevisiae, in order to show which of the six functional parameters of the model differed significantly with the yeast population. Although some parameters (hexose fractions converted to ethanol and glycerol) did not change, the kinetic constant related to the inactivation rate of the yeast population showed by S. cerevisiae assumed a value significantly higher (approximately 50-fold) than that observed for S. bayanus, while this latter population was ten times less affected by ethanol than S. cerevisiae. Although no remarkable differences could be found between the ability shown by the two yeast populations to convert hexoses (D-glucose and D-fructose), the tolerance for ethanol accumulation changed strongly. The conversion rate of these two hexoses by S. bayanus was affected less (about ten thousand-fold) by ethanol than that of S. cerevisiae. [ABSTRACT FROM AUTHOR]

Eight malolactic bacterial strains were isolated through enrichment cultures kept at 10°C from different Tuscan wines. Six strains were identified as Oenococcus oeni by ARDRA and species specific PCR. Two strains were tentatively assigned to L.brevis. A kinetic approach was used to assess their activity at 25° and 10°C. All strains induced a remarkable conversion of L-malate at 25°C. Four strains showed a measurable fermentative activity at 10°C, among which L. brevis LB2 gave a significant conversion of L-malate. The kinetic activity of this strain appears to be unaffected by the components dissolved in wine. [ABSTRACT FROM AUTHOR]

Enzymatic preparations containing β-glucanases are utilised extensively in winemaking to facilitate the filtration of musts and wines coming from grapes affected by Botrytis cinerea, and to induce the release of mannoproteins and oligosaccharides from the cell walls of yeasts. The aim of the present work was to investigate the possible inhibitory effect of some wine components, and in particular of ethanol, on β-glucanase activities. For this purpose, the kinetic activity of a commercial enzymatic preparation containing β-glucanases was tested utilising both model solutions (buffer solution having a pH value similar to a must/wine with or without 13% v/v of ethanol added) and a red wine. When ethanol was added to the model solution, both the kinetic constant k and glucose production suffered a decrease of about 50% compared to the values detected in the absence of ethanol. A further loss of activity (about 87%) was found using red wine as reaction medium, suggesting, as already reported in the literature, that phenols could add their inhibitory effect to that of ethanol. The results obtained provide useful suggestions that can be adopted during winemaking. To promote the hydrolysis of the possible excess of β-glucan coming from grapes affected by Botritis cinerea, it would be more convenient to add β-glucanases before a significant amount of ethanol accumulates in the must/wine, while it is not possible to avoid the negative impact of ethanol or other possible inhibitors (phenols) to promote yeast degradation in wine left on lees. [ABSTRACT FROM AUTHOR]

Monitoring is essential to ensure that environmental goals are being achieved, including those of sustainable agriculture. Growing interest in environmental monitoring provides an opportunity to improve monitoring practices. Approaches that directly monitor land cover change and biodiversity annually by coupling the wall-to-wall coverage from remote sensing and the site-specific community composition from environmental DNA (eDNA) can provide timely, relevant results for parties interested in the success of sustainable agricultural practices. To ensure that the measured impacts are due to the environmental projects and not exogenous factors, sites where projects have been implemented should be benchmarked against counterfactuals (no project) and control (natural habitat) sites. Results can then be used to calculate diverse sets of indicators customized to monitor different projects. Here, we report on our experience developing and applying one such approach to assess the impact of shaded cocoa projects implemented by the Instituto de Manejo e Certificação Florestal e Agrícola (IMAFLORA) near São Félix do Xingu, in Pará, Brazil. We used the Continuous Degradation Detection (CODED) and LandTrendr algorithms to create a remote sensing-based assessment of forest disturbance and regeneration, estimate carbon sequestration, and changes in essential habitats. We coupled these remote sensing methods with eDNA analyses using arthropod-targeted primers by collecting soil samples from intervention and counterfactual pasture field sites and a control secondary forest. We used a custom set of indicators from the pilot application of a coupled monitoring framework called TerraBio. Our results suggest that, due to IMAFLORA's shaded cocoa projects, over 400 acres were restored in the intervention area and the community composition of arthropods in shaded cocoa is closer to second-growth forests than that of pastures. In reviewing the coupled approach, we found multiple aspects worked well, and we conclude by presenting multiple lessons learned., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

This research aimed to study the effects of packaging and storage temperature on the shelf-life of an extra virgin olive oil (EVOO) as it can occur in most points of sale. The evolution of the chemical and sensory characteristics of an EVOO, initially stored in stainless steel silos under nitrogen at 12-18 °C, was evaluated after packaging. Tinplate tin (TT) and greenish glass (GG), the most used packaging containers, and temperatures of 6 and 26 °C were taken into consideration. After 125 days from packaging all the samples maintained clearness, green and yellow reflections and the positive sensory notes of bitterness and pungency of the starting EVOO. Shelf-life of EVOO was significantly affected by different storage conditions: oil samples stored in GG at 6 °C preserved for the most part the positive attributes, whereas those stored in TT at 26 °C showed a significant presence of the rancid flavor due to oxidative processes. Moreover, samples stored in GG at 6 °C maintained the highest bitterness intensity and did not show defects at the end of the storage period. The results suggest that storage in GG at a low temperature could represent a promising storage condition to slow-down the oil degradation during market storage.