•Different treatments during aging can impact outcomes of micro-oxygenation.•Intensity of phenolic changes depends on SO2, Fe with Cu and gelatin fining.•High concentrations of SO2 delay phenolic ...changes, impact color and astringency.•High levels of Fe and Cu can accelerate phenolic changes and affect color.•Gelatin fining reduces wine astringency and color intensity after long-term aging.
This work aimed to study long-term impact of micro-oxygenation and/or different aging treatments: (i) high SO2, (ii) high Fe with Cu and (iii) gelatin fining on Plavac mali red wine phenolic and in-mouthfeel sensory development in barrels and furthermore in bottles. Results showed that outcomes of micro-oxygenation strongly depend on aging treatments. High SO2 concentration during aging in barrels and bottles delayed typical phenolic changes and slightly contributed to astringency and lower color intensity, particularly in wine that was not micro-oxygenated. High metal concentrations and gelatin fining promoted intensive polymerization of proanthocyanins and a lower percentage of prodelphinidins after long-term aging in barrels. Also, flavan-3-ol and anthocyanins transformation rates in micro-oxygenated wines of both treatments significantly differed from their controls. Gelatin fining proved to be a very effective treatment for astringency reduction, particularly when combined with micro-oxygenation, but fined wines after long term aging in bottles showed lower color intensity.
In the present study phenolic grape skin extracts were prepared by using five choline chloride based natural deep eutectic solvents (NADESs) containing glucose, fructose, xylose, glycerol, malic acid ...and valorised by testing their biological activity in vitro using two human tumour cell lines (HeLa and MCF-7). Initially, used NADESs were investigated regard to their toxicity and low cytotoxicity of solvents was observed toward HeLa and MCF-7 cells (EC50 values > 2000 mg/L). Among used choline chloride based NADESs, the one containing malic acid showed the best performance concerning extraction efficiency (total phenolic and total anthocyanin were 91 and 24 mg/g dw), as well as antioxidant (ORAC values were 371 μmol TE/g dw) and antiproliferative activity (percentage of cell viability were about 20%). Herein, for the first time it was showed that NADES components could be chosen not only to fine-tune solvent physicochemical characteristics but also to enhance biological activity of extracts prepared in NADESs. Therefore, our research confirmed that NADESs are excellent and promising choice of solvents for sustainable and green extraction, which will lead to its novel application in food and pharmaceutical industry.
•Grape skin phenolics were successfully extracted with deep eutectic solvents.•Deep eutectic solvents are more effective as extraction solvents than methanol.•Applied deep eutectic solvents possesses low cytotoxicity toward tumour cell lines.•Proper choice of extraction solvent could enhance plant extract bioactivity.
The effect of different extraction conditions and storage time of prepared infusions on the content of bioactive compounds of green teas and their antioxidant capacity were investigated. The content ...of total phenols, total flavonoids and total non-flavonoids in green teas was determined spectrophotometrically, while 7 flavan-3-ols, 6 phenolic acids and 3 methylxanthines were identified and quantified by using high performance liquid chromatography (HPLC–PDA). Among the tested green teas bagged green tea
Twinings of London was recognized as the richest source of phenolic compounds (3585
mg/L GAE of total phenols). The most abundant phenolic constituents of green tea were flavan-3-ols, of which EGCG was prevailing in all teas (94.54–357.07
mg/L). The highest content of caffeine, as the most abundant methylxanthine, was determined in powdered green tea. The findings of this investigation suggest that extraction efficiency of studied bioactive compounds from green tea depends on the extraction conditions and that maximum extraction efficiency is achieved during aqueous extraction at 80
°C, for 5′ (powder), 15′ (bagged) and 30′ (loose leaf). In order to determine the antioxidant capacity of teas the DPPH, ABTS and FRAP assays were applied. Regardless of the extraction conditions all green teas exhibited significant antioxidant capacity
in vitro, which was in correlation with their phenolic content, confirming that green tea is one of the best dietary sources of antioxidants.
Research into non-thermal wine processing technologies is constantly evolving due to the increasing trend towards high-quality, minimally processed, and preservative-free wines. Technologies such as ...high-power ultrasound, high hydrostatic pressure, pulsed electric field, ultra-high pressure homogenization, and, more recently, cold plasma are some of the best examples currently being explored. This article provides an overview of the latest scientific research into these five non-thermal technologies and their current status in relation to winemaking. By exploring the potential applications of these technologies, it becomes possible to enhance extraction, shorten maceration time, inactivate microorganisms and oxidative enzymes, reduce the addition of chemical additives, accelerate aging, improve wine quality, and much more. However, further experiments are necessary to better comprehend the short- and long-term impacts on the overall quality of the wines produced, especially in terms of sensory characteristics and consumer acceptance. Optimizing processing conditions and scaling up are also of paramount importance to ensure better performance of these technologies at the various stages of winemaking. Additionally, a combined technologies approach has been highlighted as one of the future directions to overcome the limitations of processing with a single technology.
The aim of this work is to develop an industrially suitable process for the sustainable waste disposal in wine production. The proposed process involves the development of an environmentally friendly ...method for the isolation of biologically active compounds from Graševina grape pomace according to the green extraction principles, in order to obtain a ready-to-use extract. In this process, deep eutectic solvents (DES) were used as extraction solvents. Aiming to save time in selecting the optimal DES that would provide the most efficient Graševina pomace polyphenols extraction, the user-friendly software COSMOtherm was used and 45 DES were screened. Moreover, the prepared extracts were chemically and biologically characterized to confirm their safety for human application. Computational and experimental results proved the applicability of COSMOtherm in the selection of the optimal DES for the environmentally friendly preparation of the ready-to-use extract from Graševina grape pomace with expected application in the cosmetic industry.
The aim of this study was to evaluate the effects of mechanical (pigeage, délestage and remontage) and oxygenation treatments on the phenolic and aromatic compounds and sensory characteristics of ...Teran wines. The experiment included a 20-day maceration period, during which the above-mentioned treatments were applied, as well as the post-fermentation processes of pressing and first rack. The analysis of phenolic, chromatic and aroma compounds and the sensory characterization of the wines were used to describe the effects of the treatments investigated. After the observed maceration period, remontage resulted in wines with the highest total phenols (2682.0 ± 14.8 mg GAE/L). In contrast, délestage resulted in the lowest total phenols (2499.1 ± 17.6 mg GAE/L) and total anthocyanins (530.1 ± 2.8 mg/L) and had the strongest effects on chromatic characteristics. The post-fermentation processes (pressing, racking) showed similar trends and resulted in higher phenolic concentrations in the remontage wine, while the délestage was again characterized by lower total phenol and anthocyanin concentrations. In addition, the délestage wine contained a higher concentration of almost all analyzed esters and two higher alcohols (2-methylpropan-1-ol and 1-hexanol), while the remontage wine had the highest concentration of 2-phenylethanol and 3-methylbutyl acetate. Finally, maceration proved to be a key factor in defining the wines’ sensory characteristics, with the remontage-treated wine showing the best overall quality.
In this study, eight different types of imidazolium-based ionic liquids (ILs) were applied as new solvents in the extraction of flavonoids from grape skin, and compared to the conventional organic ...solvent extraction that was not reported earlier. The structure of anions, cations and concentration of ILs significantly affected extraction yields. The highest mass fractions of proanthocyanidins and anthocyanins were obtained with 2.5 mol/L of 1-butyl-3-methylimidazolium bromide C
mimBr and 2.5 mol/L of 1-ethyl-3-methylimidazolium bromide C
mimBr, respectively. The studied ILs provided an excellent preliminary result in the extraction of anthocyanins. Significantly higher mass fractions of total and all free anthocyanins were extracted with 2.5 mol/L of C
mimBr and 2.5 mol/L of 1-methylimidazolium hydrogen sulfate mimHSO
than with conventional solvent with the exception of anthocyanin-3-O-acetylmonoglucosides in the latter. On the other hand, 2.5 mol/L of C
mimBr and 2.5 mol/L of 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate sC
mimHSO
showed significantly higher selectivity towards anthocyanin-3-O-acetylmonoglucosides and anthocyanin-3-(6-O-
-coumaroyl)monoglucosides.
The aim of this study was to investigate use of high hydrostatic pressure (HHP) along with different antioxidants (glutathione and SO
) as an alternative method for wine preservation and production ...of low-SO
wines. In the first phase of the study, low-SO
young red and white wines were pressurized at three pressure levels (200, 400 and 600 MPa) for 5, 15 and 25 min at room temperature, and analyzed immediately after treatments. Additionally, for the wine aging experiment, red and white wines with standard-SO
, low-SO
+glutathione and low-SO
content were treated with HHP treatment (200 MPa/5 min) and stored for 12 months in bottles. Color parameters, phenolic and aroma compounds were determined. The sensory evaluation was also conducted. HHP showed very slight, but statistically significant changes in the chemical composition of both red and white wine right after the treatment, and the main variations observed were related to the different pressures applied. Furthermore, during aging, most of the differences observed in chemical composition of pressurized wines, both red and white, were statistically significant, and greater in wines with a lower content of antioxidants. However, after 12 months of aging, some differences between unpressurized and pressurized samples with standard SO
content were lost, primarily in aroma compounds for red wine and in color and phenolics for white wine. Additionally, similar values were obtained for mentioned characteristics of red and white wines in pressurized samples with standard SO
and low SO
+glutathione, indicating that HHP in combination with glutathione and lower doses of SO
might potentially preserve wine. The sensory analysis confirmed less pronounced changes in the sensory attributes of pressurized wines with higher concentration of antioxidants. Furthermore, the treatments applied had a slightly higher effect on the sensory properties of white wine.
The aim of this research was to investigate the short- and long-term effects of thermosonication and different physicochemical properties of wine on culturability, viability, and metabolic activity ...of Brettanomyces bruxellensis yeast. Thermosonication was conducted at 43 °C during 1, 2, and 3 min, while wine variations included several pH, alcohol, and sugar levels. Cell culturability and viability were determined immediately after treatment and during 90 days of storage, while metabolic activity was determined after 90 days of storage. Results showed that, although culturability was not confirmed in dry wines immediately after 3 min of treatment, thermosonication did not result in complete inactivation of the B. bruxellensis population. Herein, the first evidence of a viable but not culturable (VBNC) state of B. bruxellensis after thermosonication exposure was observed. Moreover, thermosonication reduced the production of volatile phenols. Obtained results suggest application of thermosonication for reduction of the B. bruxellensis population only in early stages of wine contamination.
Pretreatment of grape pomace seeds with a pulsed electric field (PEF) was applied to improve the extraction yield of cold-pressed grape seed oil. The effects of different PEF conditions, electric ...field intensities (12.5, 14.0 and 15.6 kV/cm), and durations (15 and 30 min) on the oil chemical composition were also studied. All PEF pretreatments significantly increased the oil yield, flow rate and concentration of total sterols (p < 0.05). In addition, similar trends were observed for total tocochromanols and phenolic compounds, except for PEF pretreatment under the mildest conditions (12.5 kV/cm, 15 min) (p < 0.05). Notably, the application of 15.6 kV/cm for 30 min resulted in the highest relative increase in oil yield and flow rate (29.6% and 56.5%, respectively) and in the concentrations of total tocochromanols, nonflavonoids, and flavonoids (22.1%, 60.2% and 81.5%, respectively). In addition, the highest relative increase in the concentration of total sterols (25.4%) was achieved by applying 12.5 kV/cm for 30 min. The fatty acid composition of the grape seed oil remained largely unaffected by the PEF pretreatments. These results show that PEF pretreatment effectively improves both the yield and the bioactive properties of cold-pressed grape seed oil.
PDF
