Higher Concentrations Of Esters Research Articles

Effects of grapevine canopy leaning on grape composition and wine quality of ‘Bobal’

Exploring new field strategies for adapting winegrowing regions to the adverse effects of climate change becomes imperative. This study focuses on the effects of canopy architecture through the trellis systems leaning of North–South oriented vineyard’s rows vertical shoot positioned (VSP) system by 30° towards either the East (ESP) or the West (WSP) as a possible adaptation technique. The trial was conducted over two seasons in a Vitis vinifera L. cv. Bobal vineyard located in Requena (Valencia), eastern Spain, under a temperate-warm climate. The canopy leaning was considered to affect the radiation load and its timing with potential effects on vine physiology and grape metabolism and, consequently, on grape and wine quality. Leaning treatments affected vegetative growth, likely due to slight differences in vine water status. In comparison to VSP and ESP, WSP intercepts more light in the morning, when the photosynthetic capacity of the vines is at its highest. However, this results in a more negative vine water potential, which in turn leads to a reduction in vigour with no impact on yield. Musts from the WSP showed a tendency to increase total acidity compared to VSP, while ESP tended to decrease it. This was likely due to the reduction in temperature within the cluster microclimate in WSP in comparison to the ESP and VSP treatments. In addition, musts from the WSP treatment showed higher colour intensity, anthocyanins and polyphenols, potentially attributable to its more negative potentials, likely due to its more negative potentials, which may have prompted the synthesis of phenolic compounds. Consequently, wines from the WSP treatment displayed higher total acidity and lower pH, as well as higher colour intensity, anthocyanins, and polyphenolic content. In addition, WSP wines had higher concentrations of esters and higher alcohols. The improvements in grape and wine composition are likely due to an increased cluster radiation interception in the morning and reduced heating in the afternoon when VPD is higher. Our findings demonstrate that canopy management by leaning VSP vines towards the West can be a useful technique for adapting grape and wine composition to climate change and provide insights into its physiological basis.

Yeast extracts weakened warmed-over flavor in surimi gels made from silver carp due to the masking effect by high concentrations of pyrazines and esters.

Warmed-over flavor (WOF) is an off-flavor in surimi gels. Yeast extract (YE) could improve the aroma properties of food. However, the effect of YE on the WOF in surimi gels and its mechanism was still unclear. In this study, aroma profiles, the composition of aroma compounds and aroma precursors, concentrations of WOF compounds, and thiobarbituric acid reactive substances (TBARS) of surimi gels with different amounts of YE were investigated by molecular sensory science and chromatographic techniques. Moreover, the effect of pyrazines and esters introduced by YE on WOF was also tested by sensory analysis. The addition of no less than 1% YE to surimi gels significantly weakened WOF. However, YE did not decrease the concentrations of WOF compounds and did not change the fatty acid composition and TBARS in surimi gels. Conversely, the addition of YE significantly increased the contents of free amino acids, N-containing compounds, and esters in surimi gels. The contents of total free amino acids, 2,6-dimethylpyrazine, and ethyl acetate in surimi gels with 2.5% YE were 1.5, 21, and 2.1 times higher than those in the control, respectively. Additionally, the sensory results of the spiked aroma models containing WOF compounds, 2,6-dimethylpyrazine, and esters showed that more than 9.4µg/kg of 2,6-dimethylpyrazine with a baked-potato note and more than 6.1µg/kg of ethyl acetate and 11.2µg/kg of butyl acetate with a fruity note could significantly mask WOF. In conclusion, WOF in surimi gels could be masked by YE due to the high concentrations of pyrazines and esters. Practical Application: Yeast extracts could decrease the warmed-over flavor (WOF) due to the high concentrations of pyrazines (baked-potato note) and esters (fruity note). This finding extends the application of yeast extracts in the food industry. On the other hand, this study presents a reasonable solution for the reduction of WOF in surimi products.

Comparative study of volatile organic compound profiles in aromatic and non-aromatic rice cultivars using HS-GC–IMS and their correlation with sensory evaluation

Analyzing of volatile organic compounds (VOCs) is important in rice quality control and breeding aromatic cultivars. This study utilized HS-GC–IMS, known for its simplicity, high sensitivity, and low cost, to analyze VOCs in 59 aromatic and 6 non-aromatic rice cultivars. The aromatic intensity of each rice cultivar was determined by artificial sensory evaluation, thus the correlation between sensory evaluation scores and VOC peak volumes was explored. A total of 77 VOCs were identified, with aromatic cultivars exhibiting prevalent short-chain aliphatic aldehydes, alcohols, and ketones, while non-aromatic samples contained higher concentrations of esters, furans, terpenes, and benzene derivatives. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) based on VOC data effectively distinguished the two rice types, and 35 VOCs were regarded as the marker VOCs contributing to the volatile variations. Furthermore, the correlation analysis between sensory evaluation and VOC markers revealed that most of these VOCs had a positive correlation with the sensory evaluation scores, with 1-pentanol, 2-acetyl-1-pyrroline (D), and 1-hexanol (M) exhibiting the highest correlation coefficients. Meanwhile, most VOC markers also exhibited positive correlations with other volatiles. The results confirm the suitability of HS-GC–IMS for VOC detection and rice category discrimination.

Metallurgical slag used for efficient growth of Chlorella pyrenoidosa to achieve CO2 conversion to biodiesel

AbstractMetallurgical slag such as solid waste generated in the steel industry carries environmental pollution risks, but it is rich in nutrients required by microalgae. Metallurgical slag used for carbon capture and biomass energy conversion has multiple benefits: (i) reduction and harmless treatment of metallurgical solid waste, (ii) assisting in carbon neutrality by efficient carbon fixation, and (iii) production of biodiesel from CO2. In this study, AOD, BOF, BFS, HVS, and VTS slag were applied to culture Chlorella pyrenoidosa (C. pyrenoidosa) with the regulation of growth, carbon fixation, and lipid synthesis. An excellent fixed amount of CO2 with 94.59 mg is obtained from C. pyrenoidosa biomass at BOF slag added (mass ratio of CO2 captured/microalgae/slag with 1.99/1.00/10.53) since high Ca/Mg mass ratio of 419 (8.38 mg/L Ca and 0.02 mg/L Mg), no Cr and low concentration of Al (0.04 mg/L) contribute to regulating antioxidant enzyme activity (SOD and POD) to resist ROS and improving PEPC activity to reduce carbon flux toward lipid to promote biomass synthesis. Both metal concentrations from Ca (5.86 mg/L), Mg (0.05 mg/L), Al (0.42 mg/L), and Cr (0.006 mg/L) and suitable pH (10.53) in AOD leaching solution at solid/liquid ratio of 0.5 g/L change carbon flow toward efficient lipid synthesis (47.07 wt%) by continuously providing raw materials and energy by regulating ACC, ME, and PEPC activities. High value‐added biodiesel with high concentrations of C16 and C18 methyl esters from lipid of C. pyrenoidosa is achieved, following other ecological and economic benefits including 197 mg CO2 captured and 2198 mg AOD applied with harmless. In this study, C. pyrenoidosa is cultured with elements from metallurgical slag solid waste, which promotes C. pyrenoidosa efficient carbon fixation to assist in carbon neutrality, and provides guidance for CO2 conversion to high‐value‐added products with low cost.

Fungal-Bacterial Mutualism: Species and Strain-Dependent Simultaneous Modulation of Branched-Chain Esters and Indole Derivatives in Fermented Sausages through Metabolite Cross-Feeding.

The precise impact of species and strain diversity on fungal-bacterial interactions and the overall community functioning has remained unclear. First, our study revealed how Debaryomyces hansenii influences diverse bacteria to accumulate key metabolites in a simulated fermented food system. For flavor, D. hansenii promoted the accumulation of branched-chain esters in Staphylococcus xylosus by promoting growth and facilitating the precursor branched-chain acids transformations but hindered the accumulation of Staphylococcus equorum. Furthermore, fungal-bacterial interactions displayed diversity among S. equorum strains. For bioactive compounds, species and strain diversity of lactic acid bacteria (LAB) also influences the production of indole derivatives. Then, we investigated specific metabolic exchanges under reciprocal interaction. Amino acids, rather than vitamins, were identified as the primary drivers of the bacterial growth promotion. Moreover, precursor transformations by D. hansenii played a significant role in branched-chain esters production. Finally, a synthetic community capable of producing high concentrations of branched-chain esters and indole derivatives was successfully constructed. These results provide valuable insights into understanding and designing synthetic communities for fermented sausages.

Impact of two new non-conventional yeasts, Candidaoleophila and Starmerella lactis-condensi, isolated from sugar-rich substrates, on Frappato wine aroma

The interest of non-Saccharomyces yeasts in wine fermentation increased constantly in last years. This study reports for the first time the enological potential of two strains Starmerella lactis-condensi MN412 and Candida oleophila YS209. In an innovative way, these strains were used in winemaking to improve floral and fruity aroma of Frappato red wine, which has not been explored. The enological performances of the two non-Saccharomyces strains were compared to a wine strain of Starmerella bacillaris, namely Cz3, previously characterized in winemaking conditions. In these three cases, the non-Saccharomyces strain was sequentially inoculated with S. cerevisiae wine strain NF213, used as control. The St. lactis-condensi MN412 was isolated from Sicilian manna, a sugar-rich matrix, extracted from Fraxinus angustifolia trees (Oleaceae). The strain C. oleophila YS209 was isolated from honey by-products. Microbiological counts showed the ability of MN412 and YS209 to maintain high counts up to 6 days of alcoholic fermentation. Regarding chemical parameters, Cz3 showed the highest glycerol production. Analysis of VOCs revealed that the trials with non-Saccharomyces yeasts were characterized by a higher concentration of esters that contributed positively to the fruity aroma of the wines. The sensory analysis confirmed that the use of MN412 and YS209 impacted positively the final wines in terms of fruity and floral intensity, respectively, while did not generate sensory defects. In conclusion, non-conventional yeasts represent strategy to improve floral-fruity freshness of wine aroma and sugar-rich matrices such as manna ash and honey might represent novel ecological niches as source of potential oenological yeast.

Assessment of the impact of unmalted cereals, hops, and yeast strains on volatolomic and olfactory profiles of Blanche craft beers: A chemometric approach.

This study investigated the impact of changes in craft beer formulation, by modifying the unmalted cereal [(durum (Da) and soft (Ri) wheat), emmer (Em)], hops [Cascade (Ca) and Columbus (Co)], and yeast strains [M21 (Wi) - M02 (Ci)], on volatolomic, acidic, and olfactory profiles. Olfactory attributes were evaluated by the trained panel. Volatolomic and acidic profiles were determined by GC-MS. The sensory analysis detected significant differences for 5 attributes, including olfactory intensity and finesse, malty, herbaceous, and floral notes. Multivariate analysis of volatiles data, showed significant differences among the samples (p<0.05). DaCaWi, DaCoWi, and RiCoCi beers differ from the others by their higher concentrations of esters, alcohols, and terpenes. A PLSC analysis was carried out between volatiles and odour attributes. As far as we know, this is the first investigation that shed light on the impact of 3-factors interaction on the sensory-volatolomic profile of craft beers, through a comprehensive multivariate approach.

A multivariate approach to explore the volatolomic and sensory profiles of craft Italian Grape Ale beers produced with novel Saccharomyces cerevisiae strains.

This study investigated the influence of three Saccharomyces cerevisiae strains, selected from different matrices - CHE-3 (cherry), P4 (sourdough) and TA4-10 (grape must) - on characteristics of Italian Grape Ale (IGA) beers obtained at microbrewery scale. A multidisciplinary approach, combining results from analysis of chemical, volatile and organoleptic profiles of the beers, was adopted to underline the relationships between yeast starter and the quality of final products. Detection volatile organic compounds (VOCs) by Gas-Chromatography coupled with Mass Spectrometry (GC-MS) after extraction carried out by head-space micro-extraction (HS-SPME) revealed that the beer obtained by P4 strain differed from the others for its higher concentrations of esters, alcohols, and terpenes as confirmed by PCA (principal component analysis) and Cluster heatmap. Furthermore, sensorial analysis and consumer test showed that this sample differed from others by more pronounced notes of "fruity smell and floral" and "olfactory finesse," and it was the most appreciated beer for smell, taste, and overall quality. Conversely, CHE-3 was the sample with the lowest concentrations of the identified volatiles and, together TA4-10, showed the highest scores for smoked, yeast, malt, and hop notes. As far as we know, these are the first results on the application of indigenous S. cerevisiae strains in the production of craft IGA beers analyzed through a complex multivariate approach.

Biowaxes from Palm Oil as Promising Candidates for Cosmetic Matrices and Pharmaceuticals for Human Use.

The production of waxes from vegetable oils, such as palm oil, for use as a base material in products for human applications is an alternative to those derived from petroleum and animals. Seven palm oil-derived waxes, called biowaxes (BW1-BW7) in this work, were obtained by catalytic hydrotreating of refined and bleached African palm oil and refined palm kernel oil. They were characterized by three properties: compositional, physicochemical (melting point, penetration value, and pH), and biological (sterility, cytotoxicity, phototoxicity, antioxidant, and irritant). Their morphologies and chemical structures were studied by SEM, FTIR, UV-Vis, and 1H NMR. The BWs presented structures and compositions similar to natural biowaxes (beeswax and carnauba). They had a high concentration of waxy esters (17%-36%) with long alkyl chains (C, 19-26) per carbonyl group, which are related to high melting points (<20-47.9 °C) and low penetration values (2.1-3.8 mm). They also proved to be sterile materials with no cytotoxic, phototoxic, antioxidant, or irritant activity. The biowaxes studied could be used in cosmetic and pharmacological products for human use.

The Effect of Mash-In Temperature on the Characteristics and Flavor Stability of Pilsner-Type Beer

Beers were brewed at mash-in temperatures of 35 °C, 50 °C, and 65 °C, and their flavor profiles and stability were examined. Beers with mash-ins at 35 °C and 50 °C exhibited full-bodied taste and estery sensory qualities with higher concentrations of esters and amino acids. Higher extract yields were obtained in wort with mash-ins at 35 °C and 50 °C, the optimal temperatures for enzymes to break down the tissue where starch granules are located. In contrast, the beer with a 65 °C mash-in temperature had a light taste and a toast-like aroma. In terms of providing nutrition for the yeast, the proteolytic process to produce amino acids seemed unnecessary for brewing beer made exclusively from malt. Following a month of storage at 30 °C, cardboard flavors predominated in beers with mash-in temperatures of 35 °C and 50 °C, while honey and sherry-like scents predominated in beers with a mash-in temperature of 65 °C. The concentrations of the 14 components contributing to the stale flavor of Pilsner-type beers, including Strecker aldehydes, did not correlate with mash-in temperature, with the exception of the concentration of (E)-2-nonenal, even though the mash-in temperatures were predicted to affect the formation of Strecker aldehydes during beer storage.

Volatile Profiles and Sensory Characteristics of Cabernet Sauvignon Dry Red Wines in the Sub-Regions of the Eastern Foothills of Ningxia Helan Mountain in China.

To elucidate the effects of the different terroir on wine aroma in six sub-regions of Eastern Foothills of Helan Mountain in Ningxia, a premium wine-producing region in China, 71 Cabernet Sauvignon wines were investigated by gas chromatography-mass spectrometry (GC-MS), check-all-that-apply (CATA), and quantitative descriptive analysis (QDA). The bidirectional orthogonal partial least squares-discriminant analysis (O2PLS-DA) results showed that the Cabernet Sauvignon dry red wines from Xixia (XX) and Yongning (YN) had similar volatile profiles due to their geographical proximity and were characterized by higher concentrations of esters, higher alcohols, and volatile phenols because the similar aromatic profiles were detected in their dry red wines. Shizuishan (SZS) and Hongsipu (HSP) wines showed clear differences compared to the wines of the other four sub-regions, being mainly characterized by relatively higher phenolic aldehydes and volatile phenols. The concentrations of methoxypyrazines and norisoprenoids varied mainly depending on the climate diversity of the sub-regions. The highest 3-isobutyl-2-methoxypyrazine (IBMP) concentration was presented in the Helan (HL) wines. The Qingtongxia (QTX) wines have the highest β-damascenone, which might be influenced by the fact that QTX has the lowest effective accumulated temperature and the highest sunshine duration among the five sub-regions. Esters including ethyl octanoate, ethyl decanoate, ethyl butanoate, ethyl hexanoate, and isoamyl acetate were the highest in HL. Additionally, the herbaceous, black berry, and red berry notes in HL and QTX were the most outstanding.

Comparison of potential Wickerhamomyces anomalus to improve the quality of Cabernet Sauvignon wines by mixed fermentation with Saccharomyces cerevisiae

Wine produced by mixed-yeast-starters of non-Saccharomyces strains and Saccharomyces cerevisiae proved to have distinctive aroma. To find more potential mixed-yeast-starters which can enhance sensory characteristics, five Wickerhamomyces anomalus strains were isolated in this paper. They were combined with S. cerevisiae respectively to co-ferment five wines. The aroma diversity and taste characteristics (intensity, astringency, complexity, and persistence) of three co-fermented wines were improved. Sc-WaG5 and Sc-WaG26 wines had higher concentrations of esters (acetate esters, ethyl esters and other esters). Sc-WaG27 wine showed highest contents of titratable acidity, total phenolic, total tannin and total anthocyanin. Additionally, it had higher level of norisoprenoids (ionone and damascenone), carbonyl compounds (2-octanone and nonanal), higher alcohols (isopentanol) and esters. Therefore, Sc-WaG27 wine possessed more complex aroma and highest sensory score. Our results highlighted that co-fermentation of the three W. anomalus strains with S. cerevisiae is a potential strategy to improve wine flavor and aroma, and enrich wine styles.

Aromatic and chemical differences between Msalais wines produced at traditional craft workshops and modern plants

The making of Msalais, a traditional wine fermented in the A′wati production region in Southern Xinjiang (China), currently undergoes a shift from traditional craft workshop (TCW) fermentation to modern plant (MP) production. Major differences in the practices, technology, and microbes used in TCWs and MPs caused the quality of MP wines somewhat deviates from high quality of TCWs wine. Exploring the sensory and chemical differences between TCW wines and MP wines will facilitate a successful shift of Msalais-making from TCWs to MPs. Here, the sensory and chemical characters of 25 TCW and MP Msalais wines were qualitatively and quantitatively analyzed. Laboratory-scale Msalais-making experiments were performed to compare the effect of winemaking conditions on the sensory characters of wine. MP wines had a stronger caramel odor, but a relatively weaker floral and fruity odors than TCW wines, while TCW wines had a significantly stronger fruity odor but a weaker caramel odor than MP wines(p < 0.05). These differences could be ascribed to the higher content of higher alcohols, furans, and methionol in MP wines, and a higher concentration of esters, fatty acids, volatile phenols, terpenes, lactones, and norisoprenoids in TCW wines. Differences in grape residue treatment, grape juice concentration, native microbial community, dissolved oxygen levels, and fermentation temperature resulted in the sensory differences between Msalais wines. These findings will help to improve the quality of MP Msalais to retain the typical sensory features of traditional TCWs wines, and allowing an objective control of the TCW and MP technologies.

Freeze-Dried Powder of Fermented Chili Paste-New Approach to Cured Salami Production.

Fermented chili powders were obtained through the freeze-drying of fermented chili pastes and used as a condiment, acidifier, antioxidant, colorant, and microbial starter carrier in fermented salami production. Fermented chili powders were examined regarding carbohydrates, organic acids, vitamin C, phenolic compounds, carotenoids, and aroma profile. High concentrations of lactic (10.57-12.20%) and acetic acids (3.39-4.10%) were recorded. Vitamin C content was identified in the range of 398-1107 mg/100 g, with maximum values for C. annuum cv. Cayenne chili powder. Phenolic compounds showed values between 302-771 mg/100 g. Total carotenoid content was identified between 544-2462 µg/g, with high concentrations of capsanthin esters. Aroma profile analysis evidenced specific compounds (1-hexanol, 2-hexanol, hexenal, E-2-hexenal) with sensory importance and a more complex spectrum for Capsicum chinense cultivar. Plant-specific lactic acid bacteria showed dominance both in fermented chili paste, chili powder, and salami. Lactic and acetic acids from the fermented chili powder reduced the pH of the filling immediately, having a stabilizing effect on the meat. Nor molds or pathogens were identified in outer limits. Based on these results, fermented chili powders could be used as starter carriers in the production of fermented meat products for exceptional sensory properties and food safety management.

Membrane retrieval after Immediately Releasable Pool (IRP) exocytosis is produced by dynamin-dependent and dynamin-independent/protein kinase C-dependent mechanisms.

The importance of the immediately releasable pool (IRP) of vesicles was proposed to reside in the maintenance of chromaffin cell secretion during the firing of action potentials at basal physiological frequencies. To accomplish this duty, IRP should be replenished as a function of time. We have previously reported that an action potential-like stimulus (APls) triggers the release of ~50% IRP, followed by a fast dynamin-dependent endocytosis and an associated rapid replenishment process. In this work, we investigated the endocytosis and IRP replenishment produced after the exocytosis of variable IRP fractions in mice primary chromaffin cell cultures. Exocytosis and endocytosis were estimated by membrane capacitance measurements obtained in patch-clamped cells. In addition to the dynamin-dependent fast endocytosis activated after the application of APls or 5ms squared depolarizations, we found that depolarizations lasting 25-50 ms, which release >80% of IRP, are related with a fast dynamin-independent, Ca2+ - and protein kinase C (PKC)-dependent endocytosis (time constant <1s). PKC inhibitors, such as staurosporine, bisindolylmaleimide XI, PKC 19-31 peptide, and prolonged treatments with high concentrations of phorbol esters, reduced and decelerated this endocytosis. Additionally, we found that the inhibition of PKC also abolished a slow component of replenishment (time constant ~8s) observed after total IRP exocytosis. Therefore, our results suggest that PKC contributes to the coordination of membrane retrieval and vesicle replenishment mechanisms that occur after the complete exocytosis of IRP.

Alcohol acyl transferase genes at a high-flavor intensity locus contribute to ester biosynthesis in kiwifruit.

Volatile esters are key compounds contributing to flavor intensity in commonly consumed fruits including apple (Malus domestica), strawberry (Fragaria spp.), and banana (Musa sapientum). In kiwifruit (Actinidia spp.), ethyl butanoate and other esters have been proposed to contribute fruity, sweet notes to commercial cultivars. Here, we investigated the genetic basis for ester production in Actinidia in an A. chinensis mapping population (AcMPO). A major quantitative trait loci for the production of multiple esters was identified at the high-flavor intensity (HiFI) locus on chromosome 20. This locus co-located with eight tandemly arrayed alcohol acyl transferase genes in the Red5 genome that were expressed in a ripening-specific fashion that corresponded with ester production. Biochemical characterization suggested two genes at the HiFI locus, alcohol acyl transferase 16-b/c (AT16-MPb/c), probably contributed most to the production of ethyl butanoate. A third gene, AT16-MPa, probably contributed more to hexyl butanoate and butyl hexanoate production, two esters that segregated in AcMPO. Sensory analysis of AcMPO indicated that fruit from segregating lines with high ester concentrations were more commonly described as being "fruity" as opposed to "beany". The downregulation of AT16-MPa-c by RNAi reduced ester production in ripe "Hort16A" fruit by >90%. Gas chromatography-olfactometry indicated the loss of the major "fruity" notes contributed by ethyl butanoate. A comparison of unimproved Actinidia germplasm with those of commercial cultivars indicated that the selection of fruit with high concentrations of alkyl esters (but not green note aldehydes) was probably an important selection trait in kiwifruit cultivation. Understanding ester production at the HiFI locus is a critical step toward maintaining and improving flavor intensity in kiwifruit.

Medium chain fatty acids and fatty acid esters as potential markers of alcoholic fermentation of white wines

AbstractAroma components of wines play an important role in the sensory quality of wines. In our paper we investigate the effect of commercially available yeast nutrients under different fermentation parameters. Caproic acid, caprylic acid, capric acid, and different fatty acid esters were used as markers of the alcoholic fermentation process. The optimal temperature for the fermentation of different white wines was at 15–16 °C, in the case of examined wines lower concentrations of fatty acids and fatty acid esters were found at this temperature. At 25–26 °C fermentation temperature very high concentrations of fatty acids and fatty acid esters were detected. Applying different nitrogen-containing wine additives we managed to achieve better aroma profiles for white wines even using musts of lower quality.

Biodegradation of DEHP by a new native consortium An6 (Gordonia sp. and Pseudomonas sp.) adapted with phthalates, isolated from a natural strongly polluted wetland

Considering the high concentration of phthalic acid esters (PAEs) in Anzali international wetland, up to 40 times higher than the environmental risk limit, the aim of this study was to obtain an effective consortium and native bacteria in the degradation of diethyl hexyl phthalate (DEHP) from sediments of this ecosystem. For this purpose, sediments of 9 stations of Anzali wetland were enriched with PAEs in waterlogged conditions at 30 °C. The results showed that the consortium An6 (containing two cultivable bacteria with phthalate degradation ability, Pseudomonas putida strain ShA (MN298858), and Gordonia alkanivorans strain Sh6 (MK460262.1)) could biodegrade 100, 100, 90.57, and 58.73% of a mixture of DMP, DEP, DBP, and DEHP at high concentration (2000 mg/L each), respectively. The separate DEHP biodegradation by the above consortium showed that it could degrade 97% of 500 mg/L of DEHP in less than 3 days. Additionally, phthalic acid (PA) and monoethyl hexyl phthalate (MEHP) as intermediate products of DEHP biodegradation were identified by UPLC-Q-TOF-MS. Phthalate consumption patterns of strains ShA and Sh6 indicate that there is a possible complementary effect among these bacteria in PAEs biodegradation. The ability of consortium An6 belonging to the most polluted area (20–43 mg/Kg DEHP) of this wetland to degrade DEHP could be caused by the exposure of the microbial community of this area to PAEs over time that gives rise to a possible adaptation. Based on the findings, consortium An6 (with novel composition) and isolated bacteria can be suggested for the efficient remediating of PAEs in the different ecosystems. • Anzali international wetland has biopotential to self-purification of high concentration of phthalates. • The microbial community of the most polluted area of the lagoon has become more compatible with PAEs and is more efficient in phthalates degradation. • The consortium An6 could degrade phthalates at 2000 mg/L in waterlogged conditions. • Gordonia alkanivorans and Pseudomonas putida together cover the biodegradation of a broader spectrum of different PAEs. • Consortium An6 efficiently degraded 500 mg/L of DEHP in less than 3 days.

Exploring the influence of grape tissues on the concentration of wine volatile compounds

Background and Aims Knowledge of varietal wine flavour and aroma compounds has improved, but gaps exist concerning how grape composition impacts wine style. This work aimed to explore the influence that different grape tissues can have on the volatile profiles of wines. Methods and Results Riesling and Cabernet Sauvignon berries were separated into skin, flesh and seeds. Two sets of fermentations were performed using separated tissues: one using an equal mass of each tissue and another where the amount of each tissue in 25 g of berries was fermented. When an equal mass of tissue was used, the seed-derived wines had a higher concentration of esters than that produced from other grape tissues. Those produced using skins had the highest concentration of lipoxygenase pathway-derived compounds, and, for Riesling, a higher concentration of monoterpenes. When the proportional amounts of each tissue found per berry were used, the flesh-derived wines generally had a higher concentration of many wine volatiles compared to the other tissues. This reflects the greater proportion of flesh tissue in the berry compared to skin and seeds. Conclusions Seed-derived compounds can enhance ester biosynthesis during fermentation and skins appear to have high lipoxygenase pathway activity. Nevertheless, the flesh makes up such a large proportion of the whole berry that it has the major influence on volatile profiles of whole berry fermentations. Significance of the Study Different berry tissues can alter wine composition in unique ways, and this can inform strategies to alter wine composition through vineyard management or the selection of new germplasm.

Respiratory quotient level variation during storage: Critical period for low oxygen tolerance, metabolism, and quality of ‘Galaxy’ apples

New technologies for apple preservation include storage under dynamic controlled atmosphere (DCA) with respiratory quotient (RQ) monitoring or chlorophyll fluorescence (CF). Therefore, this study aimed to evaluate the effects of RQ variation on the metabolism, overall quality, and volatile organic compound concentration of ‘Galaxy’ apples after long-term storage and compare them to fixed RQ levels, controlled atmosphere (CA), and DCA-CF. We also aimed to identify the period during storage in which apples are more susceptible to low oxygen damage. Fruit were evaluated after nine months of storage plus 7 d of shelf life at 20 °C. Higher RQ (1.5 and 2.0) levels throughout the storage period or the first three months resulted in higher anaerobic metabolism, increasing the internal disorders and reducing overall fruit quality, healthy fruit and flesh firmness. The results evidenced that the critical period for low oxygen damage is the first three months of storage. Overall fruit quality is better maintained when fruit were stored under DCA-CF, DCA-RQ 1.1, DCA-RQ 1.3, and changing RQ from 1.1; 1.3; 1.5, being three months at each RQ level. Moreover, more healthy fruit, higher flesh firmness, and lower physiological disorders were observed under these storage conditions, although the main ester accumulation was reduced. In general, higher 2-methylbutyl acetate and butyl acetate were observed in fruit stored under CA and high RQ levels (1.5 and 2.0). This demonstrates that even with RQ level variations during storage, it was not possible to obtain apples with high overall quality and ester concentrations under the same storage condition.