Search Results (34)

Black tea is widely consumed worldwide, and its characteristic taste and color result from fermentation, where polyphenols are enzymatically oxidized to generate major pigments, including theaflavins (TFs), thearubigins (TRs), and theabrownins (TBs). This study investigated the effects of increased oxygen treatment during fermentation on the flavor attributes and chemical properties of Congou black tea. Fresh tea leaves (variety “Fuyun 6”) were subjected to four oxygen treatments: 0 h (CK), 1 h (TY-1h), 2 h (TY-2h), and 3 h (TY-3h), with oxygen supplied at 8.0 L/min. Sensory evaluation revealed that oxygen-treated samples exhibited tighter and deeper-colored leaves, a redder liquor, fuller taste, and a sweeter fragrance compared with CK. Chromatic analysis showed significant increases in redness (a*) and luminance (L*), alongside reduced yellowness (b*), indicating enhanced liquor color. Chemical analyses demonstrated elevated levels of TFs, TRs, and TBs in oxygen treatments, with TRs showing the most pronounced increase. Non-targeted metabolomics identified 2318 non-volatile and 761 volatile metabolites, highlighting upregulated flavonoids, phenolic acids, and lipids, and downregulated catechins and tannins, which collectively contributed to improved taste and aroma. Optimal results were achieved with 2–3 h of oxygen treatment, balancing pigment formation and sensory quality. These findings can provide a scientific basis for optimizing oxygen conditions in black tea fermentation to improve product quality. Full article

Increasing awareness of protecting the environment from chemically aided naive ecosystem degradation has encouraged the use of eco-friendly (biomass) materials in industrial production globally. This study investigated the application of a natural wine-colored extract from Brazilian plume (BP) leaf, obtained through a microwave-assisted modern aqueous extraction technique, for toxic-free dyeing of mordant-functionalized cotton fabric. Dyeing of mordanted cotton fabric was optimized by varying dyeing parameters, such as dyeing contact time (10 to 90 min), pH (1 to 11), liquor ratio (1:5 to 1:30), and temperature (30 to 90 °C). UV-visible and Fourier transform infrared spectroscopic analyses confirmed that the chemical constituents of the extract were not altered by microwave radiation. The desired color strength ($K/S$) and dye-uptake (Q) were obtained at a dyeing time of 50 min, a pH of 7, a liquor ratio of 1:20, and a dyeing temperature of 60 °C. Varieties of elegant shades with desired colorfastness were developed through the involvement of less-toxic electrolyte and herbal mordants as functionalizing agents. BP extract is established as a potential sustainable and ecological colorant for textile industrial application. Full article

China is the country with the most abundant bamboo resources in the world. Using bamboo as a raw material for pulping and papermaking can save a lot of wood and protect forests. Bamboo pulping enterprises mostly adopt sulfate processes to produce a large amount of black liquor (BL), which contains monosaccharides, polysaccharides, oligosaccharides, pectin, lignin, etc. The utilization of the high-value organic matter is of great economic and environmental significance. In this study, blue-green carbon dots (C-dots) were prepared from bamboo (Lingnania chungii) kraft pulp BL using a hydrothermal method. The changes in carbohydrate content in BL in relation to hydrothermal temperature and hydrothermal time were discussed in detail. Then, a series of characterizations of BL-C-dots, prepared under one of the hydrothermal conditions (180 °C, 6 h), were performed and the BL-C-dots showed an excitation-dependent photoluminescence (PL) spectrum and a quantum yield (QY) of 2.9% in an aqueous solution. Finally, the as-prepared BL-C-dots were successfully used as fluorescent materials to develop an anti-counterfeiting code. The fluorescent code exhibited a clear outline, an excitation-tunable color, good stability, and high security, showing great anti-counterfeiting potential and realizing the high-value utilization of BL. Full article

The current study proceeded to reduce the environmental hazards spreading worldwide due to synthetic dyes. To overcome these problems, eco-friendly natural dyes are introduced as alternative sources of synthetic dyes. The present study was focused on exploring the bio-colorant of the aqueous and acidic extract of the bark of Melia azedarach L. for the dyeing of both silk and cotton samples. The results of the extraction medium specified that the aqueous extract gave maximum colorant solubility and upon fabric dyeing produced higher color strength in contrast to the acidic medium. The optimization experimentation data showed that excellent color strength of silk fabric was found at 45 min dyeing time duration, in 35:1 mL dye extract, and using 2% salt (NaCl) as an exhausting agent, whereas cotton fabric showed the maximum K/S value at 60 min dyeing time, in a 45:1 mL liquor ratio, and with the use of 2% salt. Bio-mordants produce different shades on both fabrics. Bio-mordanting experiments on silk revealed that pre-mordanting with 2% turmeric and 3% pomegranate, and post-mordanting using 3% turmeric and 2% pomegranate produced a darker shade. In the case of cotton, the pre-mordanted samples with 2% turmeric and 3% pomegranate and the post-mordanted samples with 4% turmeric and 4% pomegranate gave the highest color strengths. All the mordanted samples gave excellent fastness ratings. Overall, it has been found that Bakain bark proved to be an excellent source of tannin. The result of this study showed that it could be a cost-effective and eco-friendly dye source for textile progress. Full article

The impact of pod storage (PS) and two drying temperatures of fermented cocoa beans was investigated in Ecuador. Therefore, four variations were simultaneously carried out three times at two locations, independently: 0, 3, and 5 days of PS, dried at 60 °C and 0 days of PS, dried at 80 °C. Pod weight during storage, pulp content, pH, temperature, microbial counts, total free amino acids, protein profiles, sugars, organic acids, cut-test, fermentation index, and sensory profiles were analyzed. Minor differences in fermentation dynamics and bean quality were found between variations with and without PS. A rather accelerated fermentation with pod-stored beans was observed (e.g., faster color change, slightly lower pH in cotyledon after 48 h), along with a significantly higher maximal temperature during 24–42 h (43.1 ± 3.2 °C compared to 39.2 ± 2.0 °C without PS). More well-fermented beans were reached with PS (52.3 ± 22.6%) than without (62.7 ± 9.2%). Differences during fermentation were observed between the locations (e.g., pH, acids, sugars), but sensory evaluation indicated that the impact of location was mitigated with PS. Drying at 80 °C showed no adverse effects, as evidenced by the results of the cut-test and fermentation index. However, sensory evaluations revealed significant differences between 80 °C and 60 °C, with the former exhibiting more bitter and astringent cocoa liquor. Full article

The EU has approved the usage of gold as a food additive (E175) and it has been applied in numerous foods for coloring and decoration purposes. Different from the general assumption that edible gold is mainly present in the form of flakes or external coating in foods, this work demonstrated that gold nanoparticles (Au NPs) can be released from gold flakes and extracted under optimized conditions. To support future risk assessment associated with the exposure of Au NPs to human health, an effective approach was established in this study for both size characterization and mass determination of Au NPs released in a commercial gold-containing liquor using Asymmetric Flow Field-flow Fractionation (AF4) hyphenated with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Our results showed that no Au NPs were detected in the original liquor product and only after ultrasonication for several minutes did Au NPs occur in the ultrasound-treated liquor. Particularly, Au NPs released in the liquor can be well extracted after 100-fold enrichment of gold flakes and the subsequent ultrasonication for 25 min. Size characterization of Au NPs was conducted by AF4-ICP-MS under calibration with Au NP standards. The gold particle sizes detected ranged from 8.3–398.0 nm and the dominant size of the released Au NPs was around 123.7 nm in the processed liquor. The mass concentration of gold particles determined in the liquor sample with gold flakes concentrated and subsequently sonicated was 48.1 μg L⁻¹ by pre-channel calibration and the overall detection recoveries ranged over 82–95%. For the comparison control samples without ultrasonication, there was no detection of Au NPs. The established method was demonstrated to be useful for monitoring Au NPs in liquor and is possibly applied to other similar foodstuffs. Full article

Lignin has emerged as a promising eco-friendly multifunctional ingredient for cosmetic applications, due to its ability to protect against ultraviolet radiation and its antioxidant and antimicrobial properties. However, its typical dark color and low water solubility limit its application in cosmetics. This study presents a simple process for obtaining light-colored lignin (LCLig) from sugarcane bagasse (SCB) alkaline black liquor, involving an oxidation treatment with hydrogen peroxide, followed by precipitation with sulfuric acid. The physico-chemical characterization, antioxidant and emulsifying potential of LCLig, and determination of its safety and stability in an oil-in-water emulsion were performed. A high-purity lignin (81.6%) with improved water solubility was obtained, as a result of the balance between the total aromatic phenolic units and the carboxylic acids. In addition, the antioxidant and emulsifying capacities of the obtained LCLig were demonstrated. The color reduction treatment did not compromise the safety of lignin for topical cosmetic applications. The emulsion was stable in terms of organoleptic properties (color, pH, and viscosity) and antioxidant activity over 3 months at 4, 25, and 40 °C. Full article

Huangjin green tea (HJC) is one of the most famous regional green teas in China, and has gained attention for its unique flavor. Research on HJC has focused mainly on the synthesis of L-theanine, with fewer studies concentrating on sensory characteristics. In this study, molecular sensory science techniques, including color analysis, gas chromatography–ion mobility spectrometry, and E-tongue, were used to characterize the sensory properties of HJC, with Fuding Dabai and Anji Baicha teas used as conventional and high amino acid controls, respectively. The sensory characteristics and main quality components of HJC lie somewhere between these two other teas, and somewhat closer to the conventional control. They were difficult to distinguish by color, but significant differences exist in terms of volatile organic compounds (VOCs), E-tongue values on bitterness and astringency, and their contents of major taste components. VOCs such as (E)-2-octenal, linalool, ethyl acrylate, ethyl acetate, and 2-methyl-3-furanethiol were found to be the main differential components that contributed to aroma, significantly influencing the tender chestnut aroma of HJC. Free amino acids, tea polyphenols, and ester catechins were the main differential components responsible for taste, and its harmonious phenol-to-ammonia ratio was found to affect the fresh, mellow, heavy, and brisk taste of HJC. Full article

Tea’s biochemical compounds and flavor quality vary depending on its grade ranking. Dianhong Congou black tea (DCT) is a unique tea category produced using the large-leaf tea varieties from Yunnan, China. To date, the flavor characteristics and critical components of two grades of high-quality DCT, single-bud-grade DCT (BDCT), and special-grade DCT (SDCT) manufactured mainly with single buds and buds with one leaf, respectively, are far from clear. Herein, comparisons of two grades were performed by the integration of human sensory evaluation, an electronic tongue, chromatic differences, the quantification of major components, and metabolomics. The BDCT possessed a brisk, umami taste and a brighter infusion color, while the SDCT presented a comprehensive taste and redder liquor color. Quantification analysis showed that the levels of total polyphenols, catechins, and theaflavins (TFs) were significantly higher in the BDCT. Fifty-six different key compounds were screened by metabolomics, including catechins, flavone/flavonol glycosides, amino acids, phenolic acids, etc. Correlation analysis revealed that the sensory features of the BDCT and SDCT were attributed to their higher contents of catechins, TFs, theogallin, digalloylglucose, and accumulations of thearubigins (TRs), flavone/flavonol glycosides, and soluble sugars, respectively. This report is the first to focus on the comprehensive evaluation of the biochemical compositions and sensory characteristics of two grades of high-quality DCT, advancing the understanding of DCT from a multi-dimensional perspective. Full article

This paper describes the synthesis and characterization of seven different copper(II) coordination compounds, as well as the formation of a protonated ligand involving all compounds from the same reaction. Their synthesis required hydrothermal conditions, causing the partial in situ transformation of 5-fluoro uracil-1-acetic acid (5-FUA) into an oxalate ion (ox), as well as the protonation of the 4,4′-bipyridine (bipy) ligand through a catalytic process resulting from the presence of Cu(II) within the reaction. These initial conditions allowed obtaining the new coordination compounds [Cu₂(5-FUA)₂(ox)(bipy)]_n·2n H₂O (CP2), [Cu(5-FUA)₂(H₂O)(bipy)]_n·2n H₂O (CP3), as well as the ionic pair [(H₂bipy)⁺² 2NO₃⁻] (1). The mother liquor evolved rapidly at room temperature and atmospheric pressure, due to the change in concentration of the initial reagents and the presence of the new chemical species generated in the reaction process, yielding CPs [Cu(5-FUA)₂(bipy)]_n·3.5n H₂O, [Cu₃(ox)₃(bipy)₄]_n and [Cu(ox)(bipy)]_n. The molecular compound [Cu(5-FUA)₂(H₂O)₄]·4H₂O (more thermodynamically stable) ended up in the mother liquor after filtration at longer reaction times at 25 °C and 1 atm., cohabiting in the medium with the other crystalline solids in different proportions. In addition, the evaporation of H₂O caused the single-crystal to single-crystal transformation (SCSC) of [Cu(5-FUA)₂(H₂O)(bipy)]_n·2n H₂O (CP3) into [Cu(5-FUA)₂(bipy)]_n·2n H₂O (CP4). A theoretical study was performed to analyze the thermodynamic stability of the phases. The observed SCSC transformation also involved a perceptible color change, highlighting this compound as a possible water sensor. Full article

Large amounts of water, synthetic dyestuffs and chemicals are used in the wet processes of textile finishing, and at the end of these processes, liquors containing chemical substances create a waste load. For this reason, it is of great importance to develop new wet-finishing processes that use less water, dyestuffs and chemicals. For this purpose, the layer-by-layer deposition method (LbL) was used in this research as an environmentally friendly, sustainable method that can be used in wet-finishing processes to minimize chemical, water and energy consumption. The dyeing and functional finishing of cotton fabrics were carried out in one process by the LbL method. Cotton fabrics were pre-treated with a commercial cationic dye fixation agent and cationic charges were produced on the fabric surfaces. Reactive and direct dyestuff groups were used in the dyeing process of cotton fabrics and fluorocarbon was used in the functional finishing process. Eight and 12 dye/fluorocarbon layered structures were obtained by LbL deposition using a laboratory-type padder. Cotton fabrics were dyed and finished with the same dyes and fluorocarbon via the padding method and both samples were compared. The washing, rubbing and light color fastness properties, color strength and color difference of the dyed samples were tested. Tensile strength, air permeability, SEM graphs, contact angle, water and oil repellency analyses were performed for the treated fabrics. Full article

The purpose of this study is to propose a fully sustainable dyeing process for nylon 6. In order to achieve this goal, Rhubarb flower parts were used to produce a brown hue on nylon 6 fabric. The effects of dyeing parameters such as dyeing time, temperature, dyebath pH, M:L, salt addition, dispersing agent, and dye concentration on color strength were investigated. Using 100%owf dye in an acidic medium at boil and the material to liquor ratio of 1:30 for 75 min was determined to be the optimal condition for dyeing nylon 6 with rhubarb flower. In order to achieve acceptable color fastness, four natural mordants were applied, including walnut husks, pistachio hulls, pine cones, and green coffee. Colorimetric measurements revealed that mordanting did not affect the hue of the color compared to the non-mordant sample. In addition, diverse natural mordants produced the same color (i.e., brown) with varying color strengths, of which 10%owf walnut husk generated the strongest color. Bio-mordanted samples were also found to have excellent color fastness, thereby providing an effective substitute for metal mordants. Full article

The selection of base liquor plays a crucial role in the flavor of soaked greengage wine. This study aimed to investigate the effects of different base liquor treatments on the physicochemical characteristics and aroma composition of greengage wine. We carried out a comprehensive analysis using HPLC for the determination of organic acids and GC-MS for the determination of volatile aroma compounds, combined with sensory evaluation. The results showed that the red and yellow colors were the darkest in the high-alcohol group, while the citric acid content was the highest in the sake group (21.95 ± 2.19 g/L). In addition, the greengage wine steeped in 50% edible alcohol had more terpenes, a significantly higher concentration of acid–lipid compounds, and a more intense aroma compared to that of the low-alcohol group, whose typical aroma compounds were greatly reduced. The sensory results showed that the greengage wine treated with baijiu had a distinct alcoholic flavor, while almond flavors were more intense in the greengage wine treated with 15% edible alcohol. In this study, base liquor was used as the main influencing factor to provide new research ideas for the flavor optimization of soaked greengage wine. Full article

Membrane fouling and mineral scaling remain major drawbacks for MBR technology. Membrane fouling reduces the filtration ability in MBR systems by increasing transmembrane pressure (TMP) and thus increases the operational cost. This study focused on the application of commercially available antiscalant in a pilot MBR system and the effect of diffuser perforation diameter for the treatment of high mineral scaling propensity wastewater. Submerged flat sheet membranes (Kubota, nominal pore size: 0.4 µm) were used in the pilot-scale test unit operated in the wastewater treatment plant of ITOB Organized Industrial Zone, Izmir, Turkey. The commercially available antiscalants employed were coded AS-1 and AS-2 for antiscalant study. Long term effect of the two antiscalants employed was investigated under high mixed liquor suspended solid (MLSS) concentration (17–21 g/L) for two months of MBR operation. The effect of low MLSS concentration (10–13 g/L) was also studied without changing the concentration of antiscalant type and concentration. AS-1 was found to be more effective in terms of mineral scale control. The effect of diffuser perforation diameter (1, 3 and 5 mm) on mineral scaling minimization in MBR pilot system was also studied. The best performance with respect to membrane fouling control was found with an air diffuser having 3 mm of diffuser perforated diameter. Some quality analyses of the product water were also carried out to assess the effect of antiscalant addition on microbial activities in the MBR unit. The findings in this study reveal that the use of antiscalants has not affected biological treatment performance of MBR pilot system. The removal ranges obtained during all MBR studies were 98.47–99.9%, 84.62–99.4%, 89.5–98.5%, 86.90–99.9%, 67.01–99.2%, 75.03–93.9%, and 20.36–71.5% for total suspended solid (TSS), color, chemical oxygen demand (COD), NH4-N, PO4-P, NO₂-N, and total nitrogen (TN) respectively. Full article

Sorghum (Sorghum bicolor (L.) Moench) is a raw material that can be used as food, feed, bioenergy, and wine; it is also a gramineous crop with drought, salt, waterlogging, and high temperature resistance. However, liquor-making sorghum faces the disadvantages of having a narrow genetic basis, poor resources, and few high-quality varieties. Ethyl methane sulfonate (EMS) is a common alkylating agent that can react with one or more bases to alkylate and cause changes in the molecular structure of DNA, thereby causing mutations. It has a minimum effect on organisms and the highest efficiency. The obtained mutant populations are of great significance for cultivating new plant varieties and enriching plant germplasm resources. Therefore, in this study, ‘Hongyingzi’ a liquor-making sorghum variety, was studied using seeds treated with 0.5% EMS and 415 M3 generation plants were obtained. (1) Investigation and statistical analysis of agronomic traits in mutant libraries showed that in the M3 generation, nine important phenotypic mutant lines were obtained, including plant type, leaf blade, spike, glume, growth period, fertility, plant height, and drought resistance. The variation frequency from high to low was as follows: glume color (75.42%) > spike type (54.70%) > spike shape (47.23%) > chaff coating degree (28%) > plant growth period (23.86%) > plant height (23.61%) > absorption degree (16.14%) > branchiness (10.84%) > leaf color (4.58%) > tillering (2.16%). (2) The PCR sequencing of SbGA2ox3 from 415 sorghum M3 plants revealed that the mutation frequency of SbGA2ox3 was 1/99.02 kb. Eight plants underwent mutations, but only one line experienced missense mutations of different amino acid types, changing Ser/Ala/Val/Leu/Gln/Ser/Pro/Ala to Asn/Thr/Gly/Val/Gln/Ala/Ser. The mutant line also had shorter plant height, reduced glume coating degree, and enhanced drought resistance. The constructions of the sorghum mutant library widened the sorghum germplasm library and provided a method for sorghum breeding with a molecular basis for the functional verification of related genes and the analysis of related regulatory networks. Full article