Bottle Storage Research Articles

White wines aged in barrels with controlled tannin potential exhibit correlated long-term oxidative stability in bottle

Chardonnay and Sauvignon blanc wines aged in oak wood barrels with low and medium tannin potentials were discriminated for their abilities to resist against oxidation during bottle storage. The oak wood tannin potential was positively correlated to wines antioxidant capacity after 2 and 4 years of bottle aging. Untargeted molecular analysis revealed that the Sauvignon blanc metabolome was more affected by the tannin potential than the Chardonnay. Supervised statistical analysis highlighted the extensive oak wood contribution to the wine chemical fingerprints. Wines aged in barrel of medium tannin potential were associated with higher concentrations in antioxidant compounds such as dipeptides. Moreover, quantitative differences were observed between oak barrel derived volatile compounds. Sauvignon blanc volatile thiols appeared to decrease during bottle aging, regardless of the oak tannin potential. This study highlights the post bottling positive impact of oak wood barrel aging on wines oxidative stability, related to oak barrel tannin potential.

Influence of Protective Colloids on Calcium Tartrate Stability and the Astringency Perception in a Red Wine.

Calcium tartrate instability in wines has been a neglected topic for many years. However, it seems that this problem is gaining prominence, and the industry welcomes inputs to address this issue. Among the alternatives that winemakers use for tartrate salt stabilization, the addition of authorized protective colloids is one of the best choices because they are easy to apply and have a low energetic cost. In the present study, the same red wine was treated with five different commercially available protective colloids in triplicate. The effectiveness of such colloids on calcium tartrate potential instability was estimated, in addition to their side effects on the phenolic composition of the treated wines and their astringency perception, as assessed by sensory analyses of the treated wine. The results show that, under these trial conditions, carboxymethylcellulose is the best choice for reducing the risk of calcium tartrate precipitation in wine. Moreover, the application of protective colloids to the wines had little effect on their color, phenolic composition, or evolution during one year of bottle storage. Finally, the addition of protective colloids did not impact the astringency intensity, but it influenced the dynamic perception of astringency according to the temporal dominance of sensation analysis.

Enhancing the stability of a red organic wine through hydroxytyrosol supplementation at bottling: A time-dependent analysis

The effect of the addition of hydroxytyrosol (HT) in a red organic wine (Sangiovese 85 % and Cabernet Sauvignon 15 %) was evaluated. After six months of storage in a concrete tank, the wines were spiked with HT in three different amounts (30, 60, 120 mg/750 mL in wine) and compared with a control bottled wine (no HT addition). The bottled wines were stored at room temperature and were opened after a period of one, three, six, nine and twelve months to perform chemical and sensory analyses (T1, T3, T6, T9, and T12, respectively). Storage time was the factor that most influenced all wines parameters with respect to the different treatments. However, wine added with 60 and 120 mg/750 mL HT had a lower amount of acetic acid than the control at T3 and T6. At T6, the measured HT was negatively correlated with acetic acid (R2 = 0.81), thus suggesting that HT preserved the wine from oxidation. Later, this trend was not confirmed. The content of HT spiked was stable over twelve months of bottle storage; only the endogenous HT, which is naturally present in wine, showed a decrease of 44 % after twelve months of bottle storage. Yellowness (b*) was higher in the 30 mg/750 mL at T9 compared to the other samples. Lightness (L*) showed a decrement of 11 %, while a* (redness) increased by 21 % from T1 to T12. After T6, the wine fortified with 120 mg/750 mL was preferred by the sensory panel; however, it was the only sample to be clustered by the panel at T9 and "red fruits," "spicy", and "astringency" sensory attributes played an important role in this separation.

Exploring sources of inaccuracy and irreproducibility in the CDC bottle bioassay through direct insecticide quantification

BackgroundThe Centers for Disease Control and Prevention (CDC) bottle bioassay is a commonly used susceptibility test for measuring insect response to insecticide exposure. However, inconsistencies and high variability in insect response when conducting CDC bottle bioassays have been reported in previous publications. We hypothesized that the CDC bottle bioassay results may be compromised when expected and actual insecticide concentrations in the bottles are not equivalent and that inadequate bottle cleaning and/or loss during insecticide introduction and bottle storage steps could be responsible. We explored this hypothesis by quantifying insecticides using gas chromatography tandem mass spectrometry (GC-MS/MS) in bottles that had been cleaned, prepared, and stored according to the CDC guidelines.MethodsWe investigated the bottle cleaning, preparation, and storage methods outlined in the CDC bottle bioassay procedure to identify sources of irreproducibility. We also investigated the effectiveness of cleaning bottles by autoclaving because this method is commonly used in insecticide assessment laboratories. The two insecticides used in this study were chlorpyrifos and lambda-cyhalothrin (λ-cyhalothrin). Insecticides were removed from glass bioassay bottles by rinsing with ethyl-acetate and n-hexane and then quantified using GC-MS/MS.ResultsThe CDC bottle bioassay cleaning methods did not sufficiently remove both insecticides from the glass bottles. The cleaning methods removed chlorpyrifos, which has higher water solubility, more effectively than λ-cyhalothrin. Chlorpyrifos experienced significant loss during the bottle-coating process whereas λ-cyhalothrin did not. As for bottle storage, no significant decreases in insecticide concentrations were observed for 6 h following the initial drying period for either insecticide.ConclusionsThe CDC bottle bioassay protocol is susceptible to producing inaccurate results since its recommended bottle cleaning method is not sufficient and semi-volatile insecticides can volatilize from the bottle during the coating process. This can lead to the CDC bottle bioassay producing erroneous LC50 values. High levels of random variation were also observed in our experiments, as others have previously reported. We have outlined several steps that CDC bottle bioassay users could consider that would lead to improved accuracy and reproducibility when acquiring toxicity data.Graphical

Evolution of Aroma Profiles in Vitis vinifera L. Marselan and Merlot from Grapes to Wines and Difference between Varieties.

The fermentation process has a significant impact on the aromatic profile of wines, particularly in relation to the difference in fermentation matrix caused by grape varieties. This study investigates the leaching and evolution patterns of aroma compounds in Vitis vinifera L. Marselan and Merlot during an industrial-scale vinification process, including the stages of cold soak, alcohol fermentation, malolactic fermentation, and one-year bottle storage. The emphasis is on the differences between the two varieties. The results indicated that most alcohols were rapidly leached during the cold soak stage. Certain C6 alcohols, terpenes, and norisoprenoids showed faster leaching rates in 'Marselan', compared to 'Merlot'. Some branched chain fatty-acid esters, such as ethyl 3-methylbutyrate, ethyl 2-methylbutyrate, and ethyl lactate, consistently increased during the fermentation and bottling stages, with faster accumulation observed in 'Marselan'. The study combines the Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) model based on odor activity values to elucidate the accumulation of these ethyl esters during bottle storage, compensating for the reduction in fruity aroma resulting from decreased levels of (E)-β-damascenone. The 'Marselan' wine exhibited a more pronounced floral aroma due to its higher level of linalool, compared to the 'Merlot' wine. The study unveils the distinctive variation patterns of aroma compounds from grapes to wine across grape varieties. This provides a theoretical framework for the precise regulation of wine aroma and flavor, and holds significant production value.

Care practices of contact lens solutions and microbial contamination among wearers in Ghana

PurposeThis study sought to assess contact lens solutions care practices, and their microbial contamination among contact lens wearers in Ghana and to profile their antibiotic susceptibility pattern. MethodsThe study employed a biphasic approach which involved a cross-sectional design that investigated participants’ habits related to care for the solutions with a two-part questionnaire and a microbiological analysis of samples of contact lens care solutions of the participants for microbial contamination. A snowball sampling method provided access to 32 different contact lens wearers in four care facilities in Ghana. In most cases, the participants had no pre-existing familial relationship with each other or with the care facilities. ResultsOut of 32 samples of contact lens solutions, 30 were tested for microbial contamination. A total of 23 (76.67 %) samples of contact lens solution were found to be contaminated with Enterobacter sp. (34.80 %), Pseudomonas sp. (21.70 %), Bacilli sp. (21.70 %), Klebsiella sp. (17.20 %), and Escherichia coli (4.60 %). The duration of solution storage in the open bottle and nonadherence to manufacturer instructions for solution storage showed a statistically significant association with microbial contamination (p ≤ 0.05). ConclusionContact lens care solutions have been found to harbour multiple antibiotic-resistant bacteria that are potentially pathogenic to the corneal surface. The contamination is associated with some unhealthy solution-care practices among wearers.

Effect of cattle and horse feces storage methods on Nematode egg viability and sensitivity for egg hatch test

The aim of the present study was to validate methods of stool sample conservation for the egg hatch test (EHT). This study involved the use of a bovine naturally infected predominantly by Cooperia spp. and one equine naturally infected predominantly by cyathostomins characterized as susceptible to benzimidazoles in the EHT. Fecal samples were submitted to three treatments: aerobic methods (anaerobic storage in plastic bottles, anaerobic storage in vacuum-sealed bags or aerobic storage in plastic bags), under two temperature conditions (room temperature and refrigeration) analyzed at four different assessment times (48, 72, 96 and 120 h). As the standard test, an assay was also performed within 3 h. The tests were performed in triplicate for each drug concentration and with three experimental repetitions at one-week intervals. Two criteria were used for the storage methods: hatchability in the negative control group and sensitivity of the eggs to thiabendazole, comparing the EC50 and 95% confidence interval for each treatment to those of the standard test and the other repetitions. Bovine samples can be stored for up to 96 h and refrigerated vacuum storage can be used, ensuring hatchability of the negative control and sensitivity of the eggs to thiabendazole. For equine samples, no forms of storage were indicated due to the variation among the repetitions and the reduction in the sensitivity of the eggs to thiabendazole, which could result in a false positive detection of resistance.

The influence of drying and storage conditions on the volatilome and cannabinoid content of Cannabis sativa L. inflorescences

The increasing interest in hemp and cannabis poses new questions about the influence of drying and storage conditions on the overall aroma and cannabinoids profile of these products. Cannabis inflorescences are subjected to drying shortly after harvest and then to storage in different containers. These steps may cause a process of rapid deterioration with consequent changes in precious secondary metabolite content, negatively impacting on the product quality and potency. In this context, in this work, the investigation of the effects of freeze vs tray drying and three storage conditions on the preservation of cannabis compounds has been performed. A multi-trait approach, combining both solid-phase microextraction (SPME) two-dimensional gas chromatography coupled to mass spectrometry (SPME-GC × GC–MS) and high-performance liquid chromatography (HPLC), is presented for the first time. This approach has permitted to obtain the detailed characterisation of the whole cannabis matrix in terms of volatile compounds and cannabinoids. Moreover, multivariate statistical analyses were performed on the obtained data, helping to show that freeze drying conditions is useful to preserve cannabinoid content, preventing decarboxylation of acid cannabinoids, but leads to a loss of volatile compounds which are responsible for the cannabis aroma. Furthermore, among storage conditions, storage in glass bottle seems more beneficial for the retention of the initial VOC profile compared to open to air dry tray and closed high-density polyethylene box. However, the glass bottle storage condition causes formation of neutral cannabinoids at the expenses of the highly priced acid forms. This work will contribute to help define optimal storage conditions useful to produce highly valuable and high-quality products.Graphical

The effect of pasteurisation and storage on aroma compounds in lager

Why was the work done: To investigate the impact of pasteurisation and storage in bottle on aroma compounds in pale lager beer. How was the work done: Pale lager beer was produced at an industrial scale with 100% pilsner malt and a bottom fermenting yeast. Samples were taken of unpasteurised beer from bright beer tank, after flash pasteurisation and six months after packaging in amber glass bottles. What are the main findings: Post pasteurisation, a marked increase was found in the concentration of 2,3-pentanedione (50%) and diacetyl (33%), presumably reflecting the decomposition by heat of precurser acetohydroxy acids. There was also a marginal increase in dimethyl sulphide (6%) with little or no change in other aroma compounds. Storage for six months in bottle, also resulted in an increase in the level of 2,3-pentanedione, diacetyl and dimethyl sulphide. The linear (Pearson) correlation was > 0.8 for both dimethyl sulphide and diacetyl, and 2,3-pentanedione and diacetyl. Accordingly, it was concluded that the levels in beer of dimethyl sulphide and 2,3-pentanedione are proportionally related to diacetyl. Why is the work important: This work provides an insight into the effects on flavour and aroma of lager of flash pasteurisation and subsequent storage in bottle. The inter-relationship between aroma compounds in beer suggests that such synergies may undermine the sensory perception of threshold levels and identification of specific aromas.

Effects of Phenolic Evolution on Color Characteristics of Single-Cultivar Vitis vinifera L. Marselan and Merlot Wines during Vinification and Aging

The loss of red hue in dry red wine has been a persistent issue for wine enterprises in western China. We investigated the changes in anthocyanins and non-anthocyanin phenols during the industrial-scale fermentation and one-year bottle aging of Vitis vinifera L. Merlot and Vitis vinifera L. Marselan, respectively, using the grapes in the Ningxia region. We also examined their correlation with color characterization. The study found that both anthocyanins and non-anthocyanin phenolics were rapidly extracted from grapes during alcohol fermentation. However, their concentrations decreased rapidly during malolactic fermentation. On the other hand, Vitisin A and Vitisin B were formed during alcoholic fermentation and decreased slowly from malolactic fermentation to storage period. Directly polymerized pigments (F-A and A-F), bridged polymerized pigments (A-e-F), and flavanyl-pyranoanthocyanins (A-v-F) from the reactions of anthocyanins (A) and flavan-3-ols (F), as well as pinotins were generated during the later stages of alcoholic fermentation, and remained at a high level throughout malolactic fermentation and bottle storage. Partial least squares regression and Pearson correlation analyses revealed that the red hue (a* value) of ‘Merlot’ and ‘Marselan’ wines was closely associated with monomeric anthocyanins and F-A type pigments. Furthermore, four pinotin components were positively correlated with the red hue (a* value) of ‘Merlot’ wine. These primary red components of the two varieties had a positive correlation with the level of flavan-3-ols. The data suggest that elevating the flavan-3-ol concentration during fermentation aids in improving the color stability of red wine.

Is Airborne 2,4,6-Trichloroanisole (TCA) a Threat for Bottled Wine?

Background and Aims. This work investigated the TCA permeability of twelve types of commercial bottle closures during 24 months of bottle storage in the d5-TCA-contaminated atmosphere: medium pollution (max. ∼50 ng/L of d5-TCA in the air) and high pollution (max. ∼500 ng/L of d5-TCA in the air). Methods and Results. The d5-TCA content of wine samples and bottle closures was monitored by GC-MS analysis, and the closures of one group (comprising natural corks, agglomerated stoppers, and BVS Tin Saran™ screw caps) were found to be excellent barriers against airborne d5-TCA, i.e., no contaminant was detected in wine under any storage conditions. In contrast, a second group of closures (synthetic stoppers with low OTR, BVS Saranex™, and plastic body screw caps) allowed permeation of d5-TCA, polluting the wine when air contamination was high, albeit no d5-TCA was detected in wines following storage under medium air contamination conditions. A third group of closures (synthetic stoppers with medium and medium + OTR, MCA screw caps, and glass stoppers) allowed d5-TCA to accumulate in wine under both medium and high contamination environments. Conclusions. Some commercial bottle closures were found to permeate airborne d5-TCA, thereby contaminating bottled wine under certain storage conditions. Significance of the Study. This work provides the wine industry with insight into the potential for postbottling contamination of wine by airborne TCA.

Blueberry Wine Aging: Influence of Bottle Storage Time on Color, Anthocyanin Monomers, and Antioxidant Activity

In this paper, the influence of bottle storage time on different blueberry wines has been studied. Four blueberry wines with different fruit weight/sugar solution volume ratios and different fermentation times were stored. The storage was conducted for 12 months in darkness and at a constant temperature of 4°C. All the wines showed a similar behavior during the 12-month study period. The concentration of anthocyanins decreased significantly after the storage period. Wines obtained through partial fermentation showed a low concentration of anthocyanin monomers, and in the case of wines from total fermentation, no anthocyanin monomers could be identified. However, the wines at 12 months of storage exhibited a significant contribution to red color. The color intensity experienced a sharp decrease from 0 to 4 months, remaining unchanged until 12 months. Moreover, antioxidant activity increased during the storage process from 0 to 4 months and then remained relatively stable up to 12 months.

A Novel Technique of Extracting UCN Decay Lifetime from Storage Chamber Measurements Dominated by Scattering Losses

The neutron’s lifetime is a critical parameter in the standard model. Its measurements, particularly measurements using both beamline and ultracold neutron storage techniques, have revealed significant tension. In this work, we review the status of the tension between various measurements, especially in light of the insights provided by the β-decay correlation measurements. We revisit the lifetime measurement in a material storage chamber, dominated by losses from scattering off the walls of the storage chamber. The neutron energy spectra and associated uncertainties were, for the first time, well-characterized using storage data alone. Such models have applications in the extraction of the mean time between wall bounces, which is a key parameter for neutron storage disappearance experiments in search of neutron oscillation. A comparison between the loss model and the number of neutrons stored in a single chamber allowed us to extract a neutron lifetime of τn*=880(+158/−78)stat.(+230/−114)sys.s (68.3% C.I.). Though the uncertainty of this lifetime is not competitive with currently available measurements, the highlight of this work is that we precisely identified the systematic sources of uncertainty that contribute to the neutron lifetime measurements in material storage bottles, namely from the uncertainty in the energy spectra, as well as from the storage chamber surface parameters of the Fermi potential and loss per bounce. In doing so, we highlight the underestimation of the uncertainties in the previous Monte Carlo simulations of experiments using the technique of ultracold neutron storage in material bottles.

Effect of postharvest grape dehydration on the phenolic composition of ‘Marselan’ rose wine during aging

This study aimed to determine the effect of grape dehydration on the phenolic composition of ‘Marselan’ rose wines during aging. ‘Marselan’ grapes dehydrated for various times (9, 18, 27 days) under controlled conditions were used to produce rose wines as well as the wines were aged in bottle for 24 months. The phenolic composition of wines was determined through high-performance liquid chromatography (HPLC). It has been observed that wines obtained from dehydrated grapes were rich in phenolic compounds, with an increase in peonidin-3-O-glucoside, malvidin-3-O-glucoside, malvidin-3-O-(6-O-acetyl)-glucoside, vanillic, syringic, (E)-ferulic acids and epicatechin. Besides, the dehydration process promoted the increase of hydroxycinnamic acids and slowed down the loss of flavanols compared to the control wine during bottle storage. Through the orthogonal partial least squares discriminant analysis (OPLS-DA), the evolution of phenolic compounds in wine samples during bottle storage was facilitated by the dehydration of grapes.

Effect of Filtration Process on Oxidative Stability and Minor Compounds of the Cold-Pressed Hempseed Oil during Storage.

Cold-pressed hempseed oil (HO) has been increasingly exploited in the human diet for its excellent nutritional and healthy properties. However, it has a high content of polyunsaturated fatty acids (PUFAs) and chlorophylls, which inevitably accelerate its oxidative deterioration, especially in the presence of light. In this scenario, the filtration technology may ameliorate the oxidative stability of the oil, with positive effects on its nutritional quality and shelf life. Therefore, in this study, the oxidative stability and minor compounds of non-filtered and filtered HO (NF-HO and F-HO) were monitored over 12 weeks of storage in transparent glass bottles. F-HO showed a better hydrolytic and oxidative status than NF-HO during storage. As a result, F-HO also displayed better preservation of total MUFAs and PUFAs in the autoxidation process. Filtration consistently reduced chlorophylls, thus causing a variation in the natural color of HO. Accordingly, F-HO not only revealed an increased resistance to photooxidation but it was also suitable for storage in clear bottles within 12 weeks. F-HO predictably showed lower carotenoids, tocopherols, polyphenols, and squalene compared to NF-HO. However, filtration appeared to play a "protective role" toward these antioxidants, which had lower degradation rates in F-HO than NF-HO for 12 weeks. Interestingly, the element profile of HO was not affected by filtration and remained stable during the study period. Overall, this study may be of practical use to both producers and marketers of cold-pressed HO.

Investigation of molecular changes in wine during storage in refrigerated cabinets

Investigation of molecular changes in wine during storage in refrigerated cabinets

Susceptibility of Candida albicans, Staphylococcus aureus and Escherichia coli to Extracts of Mango (Magnifera indica)

Aim: This study was carried out to investigate the Susceptibility of Candida albicans, Staphylococcus aureus and Escherichia coli to extracts from young and mature mango (Magnifera indica) leaves and stem-bark of the same plant. 
 Study Design: The study employed statistical analysis of the data and interpretation. 
 Place and Duration of Study: Young and mature mango leaves and stem-barks were collected from the Botanical Garden, Kenule Beeson Saro-Wiwa Polytechnic, Bori, Nigeria, and taken to the laboratory for analyses. 
 Methodology: The samples were dried in an oven at 80oC for 3 days. Thereafter, 50 g of each ground mango leaves and stem-bark (young and mature of the same plant) were soaked separately in 500 ml of water, ethanol (95% v/v), and acetic acid (99.9% v/v) for another 3 days. The soaked materials were filtered through Whatman No. 1 filter paper into sterile beakers and evaporated to dryness in a water-bath at 80oC. The dried extracts obtained were reconstituted with water at concentrations of 100, 75, 50 and 25 mg/ml. Test organisms, Candida albicans, Staphylococcus aureus and Escherichia coli were obtained after proper laboratory screening of isolates from the diagnostic laboratory of the Rivers State University Teaching Hospital, Port Harcourt, Nigeria, for confirmation of identity and storage in universal bottles in a refrigerator. Sensitivity tests were carried out with the agar well diffusion method against the test organisms, using tetracycline as standard control drug (for bacteria) and fluconazole (for Candida), with cultures incubated accordingly. The measured zones of inhibition were compared with the controls and interpreted as resistant, intermediate, or susceptible to mango extracts in accordance with the interpretive guidelines published by the National Committee for Clinical Laboratory Standards (NCCLS). Assays for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also carried out.
 Results: Results obtained showed that Escherichia coli was completely susceptible to acetic acid young leaf and young bark extracts at 100 mg/ml concentrations. Staphylococcus aureus was susceptible only to Acetic acid young leaf extract at 100 mg/ml. For Candida albicans complete susceptibility was with acetic acid young bark at 100 mg/ml. mature leaf extract (100 mg/ml ), acetic acid young bark extract (100 to 50 mg/ml ), aqueous young bark extract (100 mg/ml) and acetic acid mature Candida albicans was susceptible to acetic acid young and mature bark extract at 100 mg/ml concentration. Minimum inhibitory concentration (MIC) values of acetic acid young leaf extract for all three organisms were 12.5 mg/ml. MIC of ethanolic young leaf extract for E. coli was 12.5 mg/ml whereas that for C. albicans was 50 mg/ml. Minimum bacteriocidal concentration values were same as MIC.
 Conclusion: E. coli and S.aureus were found to be most susceptible to acetic acid young leaf and stem-bark mango extracts. For C. albicans susceptibility profiles were best with aceti acid young and mature stem-bark extracts. It was also found that mango phytochemicals have broad-spectrum antibacterial activity as well as antifungal properties. The study also reveals that young mango parts contain higher bioactive substances than mature parts. Finally, it was concluded that acetic acid extracts produced the highest antimicrobial effects whereas aqueous extracts produced the least.

Effect of SO<sub>2</sub>, glutathione and gallotannins on the shelf-life of a Cortese white wine bottled with different oxygen intakes

The work aimed to study the effect of adding reduced glutathione (GSH) and/or gallotannins at bottling on the shelf-life of a Cortese white wine to limit the use of SO2.The experimental trial was carried out following a full factorial plan consisting of 8 experimental trials that differed for the content of free SO2 (2 levels: 20 and 40 mg/L), the absence/presence of gallotannins (0 and 40 mg/L) and GSH (0 and 20 mg/L). The wines of the eight trials were oxygenated respectively at 5.5 ppm and 4.0 ppm of O2. The wines oxygenated at 5.5 ppm were bottled in 135 mL bottles and monitored during 12 months of storage (colour, polyphenolic composition, GSH, free and total SO2); the wines oxygenated at 4.0 ppm of O2 were bottled in 750 mL bottles, then analysed and tasted after 15 months. The oxygen consumption rate (OCR) was measured with a luminescence-based technology. The OCR followed a first-order kinetic in all the wines, and a significant OCR acceleration was observed when increasing the concentration of free SO2. A significant increase in OCR was also observed in the samples with GSH, albeit to a lesser extent than with SO2, while the addition of gallotannins caused a decrease in the OCR. It is possible that similar mechanisms are at the basis of the acceleration of OCR observed with GSH and SO2. However, unlike SO2, GSH showed poor antioxidant efficacy in the protection of both the colour and the aromatic component, probably also due to its lower molar concentration.The presence of GSH limited the oxidative losses of SO2, mostly in wines with higher SO2 levels. However, the effect of GSH decreased over time, since after 8 months, GSH was only present in traces. The resistance to oxidative browning of wines during bottle storage depends on the concentration of free SO2 present in the medium (> 10 mg/L), therefore, higher GSH intakes, such as to ensure sufficient preservation of the free SO2 content during storage, will have to be tested to evaluate the possibility of prolonging the shelf-life of wines.

Alternative method of maize grain quality maintenance for small farmers through hermetic storage

In many countries, small corn producers generally have technological limitations during storage. hermetic storage with use of PET bottles stands out as an alternative. The objective of this study was to evaluate the hermetic storage of corn in polyethylene silo bags and PET bottles as an alternative for small producers. Maize grains were stored in polyethylene silo bags, polyethylene terephthalate (PET) bottles and glass recipients for 0, 15, 30, 45, and 60 days. Were used four repetitions for each treatment. Were evaluated the traits: infestation by insect pests (%); water content (% bu.); bulk density (kg 100 L-1); electrical conductivity (µS cm-1 g-1); percentage of germination (%). The insect species that infested the corn kernels under hermetic and non-hermetic conditions was only Sitophilus zeamais. PET bottles presented the lowest percentage of infestation among the storage containers, followed by silo bags, both presented the maximum percentages of 0.65% and 30%, respectively. Water content, bulk density, electrical conductivity e percentage of germination of the maize were preserved in both hermetic storage systems that were tested for 60 days. The use of PET bottles control S. zeamais and preserve the quality of maize for at least 60 days of storage. Our study concludes that hermetic storage in PET bottles can be particularly useful and important for small farmers.

Sedimentation Stability of Magnetorheological Fluids: The State of the Art and Challenging Issues.

Among the many factors causing particle sedimentation, three principal ingredients are heavily involved: magnetic particles, a carrier liquid (base oil), and additives (surfactant). Therefore, many works have been carried out to improve the sedimentation stability of magnetorheological fluids (MRFs) by adopting the three methods. In the particle modification stage, the weight concentration, size distribution, particle shape, coated materials, and combinations of different sizes of the particles have been proposed, while for the modification of the carrier liquid, several works on the density increment, wettability control, and the use of natural oils, lubricant oil, grease, and ethyl- and butyl-acetate oils have been undertaken. Recently, in certain recipes to improve sedimentation stability, some additives such as aluminum stearate were used to increase the redispersibility of the aggregated particles. In addition, several works using more than two recipes modifying both the particles and base oils are being actively carried out to achieve higher sedimentation stability. This review article comprehensively introduces and discuses the recipes to improve sedimentation stability from the aspects of the three ingredients. A few conceptual methodologies to prevent the sedimentation occurring via a bottle's storage on the shelves of the application systems are also presented, since, to the author's knowledge, there has not been a report on this issue. These are challenging works to be explored and developed for successful application systems' MRFs.