Stabilisation microbiologique des vins par utilisation de champs électriques pulsés

For more than ten years, pulsed electric field (PEF) technology has been the subject of a growing number of publications and patents. The technology previously reserved for laboratories is becoming more and more popular and is now a success in the food industry. Since 2015, with the help of the Occitania region, we have been studying the use of the PEF on the microbiological stability of wines on a semi-industrial scale from 5 to 12 hl/hour. This low thermal and energy consuming physical technology requires no inputs to ensure the destruction of microorganisms and microbial stabilization of wines. These tests are performed with a 7 kV/cm electric field generated between the 2 electrodes of the treatment chambers. The objective is to ensure the microbial stabilisation of wines not exceeding 50 ∘C and to cool the wine immediately after treatment without maintaining it at high temperature. The study of the effectiveness of PEF on yeast destruction is carried out during the mutage of sweet wines. The first results obtained show a very good efficiency of the yeast treatment with an instant cessation of alcoholic fermentation and a decrease in the yeast population ranging from − 3 to − 5 Log. No SO2 addition is then required. On wines contaminated by Brettanomyces, the tests show an almost total elimination (< 1/100 ml) of these yeasts by the PEF treatment. These tests also showed that a higher energy level is required to eliminate all lactic acid bacteria from wine. No effects on the physico-chemical characteristics of the wines were found. The impact on the organoleptic characteristics of wines is ongoing. An optimization of the electrical parameters is still necessary.

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INFLUENCE OF PACKAGING ON THE PHYSICO-CHEMICAL PARAMETERS AND ORGANOLEPTIC EVALUATION OF TABLE WINE

Известия вузов. Пищевая технология ◽

10.26297/0579-3009.2019.2-3.28 ◽

2019 ◽

Author(s):

Т.А. ДРОЗДОВА ◽

А.П. БИРЮКОВ ◽

Н.Ю. КАЧАЕВА ◽

Р.А. ДРОЗДОВ

Keyword(s):

Red Wine ◽

Chemical Characteristics ◽

Chemical Parameters ◽

Glass Bottle ◽

Organoleptic Evaluation ◽

Organoleptic Characteristics ◽

Physico Chemical ◽

Sweet Wines ◽

Physical And Chemical

Определены физико-химические показатели 12 образцов сухих и полусладких белых и красных столовых вин, выработанных одним предприятием и разлитых в стеклобутылку (СБ), бутылку из полиэтилентерефталата и упаковку «пакет в коробке» (ПВК) в феврале 2018 г. холодным и горячим способами, с целью установления влияния упаковки на изменение органолептического состава и физико-химических показателей столовых вин. Физико-химический анализ и дегустация представленных образцов столовых вин проведены в марте 2018 г. с использованием общепринятых методик. Установлено, что через месяц после розлива в упаковку все опытные образцы соответствовали требованиям действующей нормативной документации на данный вид продукции и обладали оптимальными физико-химическими показателями, кроме образца полусладкого красного вина в СБ, который на момент анализа был подвержен микробиологическому воздействию. Во всех исследованных образцах столовых вин обнаружен 1,2-пропиленгликоль, но его содержание не превышало допустимых норм. По итогам дегустации для сухих столовых вин рекомендован розлив в СБ, поскольку холодный розлив, применяемый при этом виде упаковки, практически не влияет на изменение органолептических характеристик продукта. Для полусладких вин рекомендуется горячий розлив, поскольку он препятствует забраживанию и задушке вина, а розлив в упаковку ПВК позволяет сохранять качество вина. Physico-chemical parameters of 12 samples of dry and semi-sweet white and red table wines produced by one enterprise and poured into a glass bottle (GB), a bottle of polyethylene terephthalate and a bag-in-box in February 2018 by cold and hot methods were determined in order to establish the influence of packaging on the change in the organoleptic composition and physico-chemical characteristics of table wines. Physical and chemical analysis and tasting of the presented samples of table wines were carried out in March 2018 using generally accepted methods. It was found that a month after filling in the package, all prototypes met the requirements of the current regulatory documentation for this type of product and had optimal physico-chemical parameters, except for the sample of semi-sweet red wine in the GB, which at the time of analysis was exposed to microbiological effects. In all the studied samples of table wines 1,2-propylene glycol was found, but its content did not exceed the permissible norms. Following the results of the tasting, bottling in the GB is recommended for dry table wines, since the cold bottling used in this type of packaging practically does not affect the change in the organoleptic characteristics of the product. For sweet wines it is recommended that hot-filling because it prevents fermenting and suffocating wine and bottling in bag-in-box allows to preserve the quality of the wine.

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The Impact of the Electric Field on Surface Condensation of Water Vapor: Insight from Molecular Dynamics Simulation

Nanomaterials ◽

10.3390/nano9010064 ◽

2019 ◽

Vol 9 (1) ◽

pp. 64 ◽

Cited By ~ 7

Author(s):

Qin Wang ◽

Hui Xie ◽

Zhiming Hu ◽

Chao Liu

Keyword(s):

Molecular Dynamics ◽

Water Vapor ◽

Electric Field ◽

Intermolecular Forces ◽

Dynamics Simulation ◽

Water Molecules ◽

Attraction Force ◽

Condensation Rate ◽

Shape Transformation ◽

The Impact

In this study, molecular dynamics simulations were carried out to study the coupling effect of electric field strength and surface wettability on the condensation process of water vapor. Our results show that an electric field can rotate water molecules upward and restrict condensation. Formed clusters are stretched to become columns above the threshold strength of the field, causing the condensation rate to drop quickly. The enhancement of surface attraction force boosts the rearrangement of water molecules adjacent to the surface and exaggerates the threshold value for shape transformation. In addition, the contact area between clusters and the surface increases with increasing amounts of surface attraction force, which raises the condensation efficiency. Thus, the condensation rate of water vapor on a surface under an electric field is determined by competition between intermolecular forces from the electric field and the surface.

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The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽

10.3390/molecules26010149 ◽

2020 ◽

Vol 26 (1) ◽

pp. 149

Author(s):

Karol Leluk ◽

Stanisław Frąckowiak ◽

Joanna Ludwiczak ◽

Tomasz Rydzkowski ◽

Vijay Kumar Thakur

Keyword(s):

Polymer Composites ◽

Polylactic Acid ◽

Matrix Material ◽

Chemical Properties ◽

Precipitated Calcium Carbonate ◽

Cellulose Fibres ◽

Shape Factors ◽

Pure Cellulose ◽

Physico Chemical ◽

The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

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Conventional and Organic Honeys as a Source of Water- and Ethanol Soluble Molecules with Nutritional and Antioxidant Characteristics

Molecules ◽

10.3390/molecules26123746 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3746

Author(s):

Magdalena Polak-Śliwińska ◽

Małgorzata Tańska

Keyword(s):

Antioxidant Activity ◽

Immune System ◽

Vitamin C ◽

Geographical Area ◽

Production Method ◽

Climatic Conditions ◽

Organic Production ◽

Organoleptic Characteristics ◽

Nutritional Characteristics ◽

The Impact

The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids.

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Impact of Preharvest and Postharvest on Color Changes during Convective Drying of Mangoes

Foods ◽

10.3390/foods10030490 ◽

2021 ◽

Vol 10 (3) ◽

pp. 490

Author(s):

Alioune Diop ◽

Jean–Michel Méot ◽

Mathieu Léchaudel ◽

Frédéric Chiroleu ◽

Nafissatou Diop Ndiaye ◽

...

Keyword(s):

Regression Models ◽

Convective Drying ◽

Color Changes ◽

Ripening Time ◽

Physico Chemical ◽

C 30 ◽

The Impact

The purpose of this study was to evaluate the impact of the harvest stage, ripening conditions and maturity on color changes of cv. ‘Cogshall’ and cv. ‘Kent’ variety mangoes during drying. A total of four harvests were undertaken, and the fruits were ripened at 20 and 35 °C for five different ripening times at each temperature. At each ripening time, mangoes were dried at 60 °C/30% RH/1.5 m/s for 5 h. A wide physico-chemical and color variability of fresh and dry pulp was created. The relationships according to the L*, H* and C* coordinates were established using mixed covariance regression models in relation to the above pre- and postharvest (preprocess) parameters. According to the L* coordinate results, browning during drying was not affected by the preprocess parameters. However, dried slices from mangoes ripened at 35 °C exhibited better retention of the initial chroma, and had a greater decrease in hue than dried slices from mangoes ripened at 20 °C. However, fresh mango color, successfully managed by the pre- and postharvest conditions, had more impact on dried mango color than the studied parameters. The preprocess parameters were effective levers for improving fresh mango color, and consequently dried mango color.

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Assessment of Physico-Chemical and Toxicological Properties of Commercial 2D Boron Nitride Nanopowder and Nanoplatelets

International Journal of Molecular Sciences ◽

10.3390/ijms22020567 ◽

2021 ◽

Vol 22 (2) ◽

pp. 567

Author(s):

Brixhilda Domi ◽

Kapil Bhorkar ◽

Carlos Rumbo ◽

Labrini Sygellou ◽

Spyros N. Yannopoulos ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Boron Nitride ◽

A549 Cells ◽

Reactive Oxygen ◽

Slight Reduction ◽

Oxygen Species ◽

Potential Toxicity ◽

Cellular Models ◽

Physico Chemical ◽

The Impact

Boron nitride (BN) nanomaterials have been increasingly explored for potential applications in chemistry and biology fields (e.g., biomedical, pharmaceutical, and energy industries) due to their unique physico-chemical properties. However, their safe utilization requires a profound knowledge on their potential toxicological and environmental impact. To date, BN nanoparticles have been considered to have a high biocompatibility degree, but in some cases, contradictory results on their potential toxicity have been reported. Therefore, in the present study, we assessed two commercial 2D BN samples, namely BN-nanopowder (BN-PW) and BN-nanoplatelet (BN-PL), with the objective to identify whether distinct physico-chemical features may have an influence on the biological responses of exposed cellular models. Morphological, structural, and composition analyses showed that the most remarkable difference between both commercial samples was the diameter of their disk-like shape, which was of 200–300 nm for BN-PL and 100–150 nm for BN-PW. Their potential toxicity was investigated using adenocarcinomic human alveolar basal epithelial cells (A549 cells) and the unicellular fungus Saccharomycescerevisiae, as human and environmental eukaryotic models respectively, employing in vitro assays. In both cases, cellular viability assays and reactive oxygen species (ROS) determinations where performed. The impact of the selected nanomaterials in the viability of both unicellular models was very low, with only a slight reduction of S. cerevisiae colony forming units being observed after a long exposure period (24 h) to high concentrations (800 mg/L) of both nanomaterials. Similarly, BN-PW and BN-PL showed a low capacity to induce the formation of reactive oxygen species in the studied conditions. Even at the highest concentration and exposure times, no major cytotoxicity indicators were observed in human cells and yeast. The results obtained in the present study provide novel insights into the safety of 2D BN nanomaterials, indicating no significant differences in the toxicological potential of similar commercial products with a distinct lateral size, which showed to be safe products in the concentrations and exposure conditions tested.

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Assessment of the Impact of Small Hydropower Plants on the Ecological Status Indicators of Water Bodies: A Case Study in Lithuania

Water ◽

10.3390/w13040433 ◽

2021 ◽

Vol 13 (4) ◽

pp. 433

Author(s):

Laima Česonienė ◽

Midona Dapkienė ◽

Petras Punys

Keyword(s):

Water Quality ◽

Benthic Macroinvertebrates ◽

Suspended Solids ◽

Ecological Status ◽

Fish Abundance ◽

Water Bodies ◽

Small Hydropower ◽

Hydropower Plants ◽

Physico Chemical ◽

The Impact

Hydropower plants produce renewable and sustainable energy but affect the river’s physico-chemical characteristics and change the abundance and composition of the aquatic organisms. The impact of large HPPs on the ecological conditions of surface water bodies have been extensively studied, but less attention has been paid to environmental impact studies of small hydropower plants (SHPs). The impact of hydropeaking on both the river flow regime and ecosystems has been well-studied for peaking mode plants, mainly medium to large-sized ones. However, for small hydroelectric power plants, and especially for those in lowland rivers, the available information on water quality, benthic macroinvertebrates communities and fish abundance, and biomass is not sufficient. Ten small hydropower plants were selected, and the ecological status of water bodies was assessed in different parts of Lithuania. The studies were performed at the riverbed upstream from the SHPs, where the hydrological regime has not changed, and downstream from the SHPs. It was found that the small hydropower plants do not affect the physico-chemical values of the water quality indicators. This study demonstrated that the total number of benthic macroinvertebrates taxa (TS) is influenced by the concentration of nitrogen and suspended solids, the water flow, the river area, and the current speed; the number of EPT (Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies)) taxa is influenced by the concentration of nitrogen and suspended solids. The studied indicators do not have a significant impact on biomass. The SHPs affect the fish abundance and biomass. The Lithuanian fish index (LFI) is influenced by the average depth and area of the river. Some SHPs operating in lowland areas may yield somewhat significant hydrograph ramping but more detailed investigation is needed to support the significance of this impact on the biological indices.

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Mixed NNLO QCD×electroweak corrections of $$ \mathcal{O} $$(Nfαsα) to single-W/Z production at the LHC

Journal of High Energy Physics ◽

10.1007/jhep12(2020)201 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

Stefan Dittmaier ◽

Timo Schmidt ◽

Jan Schwarz

Keyword(s):

Z Bosons ◽

Leading Order ◽

Current Standard ◽

Gauge Invariant ◽

Mass Distributions ◽

Self Energy ◽

Electroweak Gauge Boson ◽

First Results ◽

Invariant Part ◽

The Impact

Abstract First results on the radiative corrections of order $$ \mathcal{O} $$ O (Nfαsα) are presented for the off-shell production of W or Z bosons at the LHC, where Nf is the number of fermion flavours. These corrections comprise all diagrams at $$ \mathcal{O} $$ O (αsα) with closed fermion loops, form a gauge-invariant part of the next-to-next-to-leading-order corrections of mixed QCD×electroweak type, and are the ones that concern the issue of mass renormalization of the W and Z resonances. The occurring irreducible two-loop diagrams, which involve only self-energy insertions, are calculated with current standard techniques, and explicit analytical results on the electroweak gauge-boson self-energies at $$ \mathcal{O} $$ O (αsα) are given. Moreover, the generalization of the complex-mass scheme for a gauge-invariant treatment of the W/Z resonances is described for the order $$ \mathcal{O} $$ O (αsα). While the corrections, which are implemented in the Monte Carlo program Rady, are negligible for observables that are dominated by resonant W/Z bosons, they affect invariant-mass distributions at the level of up to 2% for invariant masses of ≳ 500 GeV and are, thus, phenomenologically relevant. The impact on transverse-momentum distributions is similar, taking into account that leading-order predictions to those distributions underestimate the spectrum.

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Fire Resistance Behaviour of Geopolymer Concrete:An Overview

Buildings ◽

10.3390/buildings11030082 ◽

2021 ◽

Vol 11 (3) ◽

pp. 82

Author(s):

Salmabanu Luhar ◽

Demetris Nicolaides ◽

Ismail Luhar

Keyword(s):

Compressive Strength ◽

Thermal Resistance ◽

Building Materials ◽

Elevated Temperatures ◽

Construction Materials ◽

Flexural Behavior ◽

Thermal Shrinkage ◽

Physico Chemical ◽

The Impact ◽

Loss Of Strength

Even though, an innovative inorganic family of geopolymer concretes are eye-catching potential building materials, it is quite essential to comprehend the fire and thermal resistance of these structural materials at a very high temperature and also when experiencing fire with a view to make certain not only the safety and security of lives and properties but also to establish them as more sustainable edifice materials for future. The experimental and field observations of degree of cracking, spalling and loss of strength within the geopolymer concretes subsequent to exposure at elevated temperature and incidences of occurrences of disastrous fires extend an indication of their resistance against such severely catastrophic conditions. The impact of heat and fire on mechanical attributes viz., mechanical-compressive strength, flexural behavior, elastic modulus; durability—thermal shrinkage; chemical stability; the impact of thermal creep on compressive strength; and microstructure properties—XRD, FTIR, NMR, SEM as well as physico-chemical modifications of geopolymer composites subsequent to their exposures at elevated temperatures is reviewed in depth. The present scientific state-of-the-art review manuscript aimed to assess the fire and thermal resistance of geopolymer concrete along with its thermo-chemistry at a towering temperature in order to introduce this novel, most modern, user and eco-benign construction materials as potentially promising, sustainable, durable, thermal and fire-resistant building materials promoting their optimal and apposite applications for construction and infrastructure industries.

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Optimal Solutions for the Use of Sewage Sludge on Agricultural Lands

Water ◽

10.3390/w13050585 ◽

2021 ◽

Vol 13 (5) ◽

pp. 585

Author(s):

Catalina Iticescu ◽

Puiu-Lucian Georgescu ◽

Maxim Arseni ◽

Adrian Rosu ◽

Mihaela Timofti ◽

...

Keyword(s):

Heavy Metals ◽

Sewage Sludge ◽

Agricultural Production ◽

Agricultural Land ◽

Chemical Characteristics ◽

Optimal Solutions ◽

Physico Chemical ◽

Agricultural Areas ◽

The Impact ◽

Made In

The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were monitored and optimal solutions for their treatment were suggested so as to allow that the sludge could be used in agriculture according to the characteristics of the soils. The content of heavy metals in the sewage sludge was closely monitored because the use of sewage sludge as a fertilizer does not allow for any increases in the concentrations of these in soils. The article identifies those agricultural areas which are suitable for the use of sludge, as well as ways of correcting some parameters (e.g., pH), which allow the improvement of soil quality and obtained higher agricultural production.

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