Final Ethanol Concentration Research Articles

Evaluation of Probiotic Saccharomyces boulardii Yeast as a Distillery Strain

The probiotic properties of the yeast Saccharomyces boulardii are fairly well recognised, and research into the use of this strain in fermentation processes has been ongoing for several years. In this article, we have described the research results to evaluate the distillery potential of S. boulardii yeast. Compared to Ethanol Red and Thermosacc Dry yeast, the probiotic strain formed slightly different amounts of volatile compounds and fermented the available sugars less vigorously. The final ethanol concentration formed by the probiotic yeast was close to that observed for the distillery strains. Rye distillates with an alcohol content of 40% (v/v) obtained with S. boulardii yeast, according to the sensory panel, were distinguished by their delicately composed flavour and were rated better than distillates after fermentation by distillery yeast. The results are promising for the possibility of production of niche distillates using probiotic yeast.

Effect of Debranning and Process Temperature on the Production of Bioethanol and Distillers’ Dried Grain with Solubles from Triticale

AbstractVery high gravity (VHG) starch to ethanol fermentation with whole and debranned triticale grains using the conventional (warm) and cold (raw starch) conversion methods were compared, with regards to fermentation performance and the quality of the distillers’ dried grains with solubles (DDGS). For both the warm and cold process configurations, debranning increased final ethanol concentration, yield (as % of theoretical maximum) and productivity. Furthermore, debranning decreased the required enzyme dosage of the cold process by 20.7%. The improvements by debranning were achieved by nutrient-recycling from the protease-treated bran and germ hydrolysate to the fermentation slurries of these processes. DDGS produced by the cold debranned process configuration had the highest protein content of 44%, while the neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of 17.8% and 13.8%, respectively, were lower than DDGS from the whole grain, making it the more favourable animal feed ingredient, particularly for monogastric animals.

Ethanol from Bagasse Obtained During Non-centrifuged Sugar Production. A Comprehensive Sustainability Analysis in the Colombian Context

AbstractThe production of biofuels is an alternative to reduce the impacts of the transformation of fossil fuel sources. In this work, the evaluation of ethanol production from the bagasse obtained during non-centrifuged sugar production (BNCS) to determine its sustainability in the Colombian context is proposed. Two pretreatments (i.e., dilute acid and alkaline) are proposed, followed by enzymatic saccharification to release glucose from cellulose. Both liquors rich in C6 sugars were followed by a fermentation stage with Saccharomyces cerevisiae, and the obtained ethanol concentration was measured. The process was simulated and evaluated to obtain metrics in technical, economic, environmental, and social terms. Also, an evaluation of the sustainability index of the process in the Colombian context was proposed. Diluted acid was the best processing pretreatment, reaching glucose and xylose concentrations of 15.13 g/L, and 12.15 g/L respectively, and a final ethanol concentration of 3.45 g/L. The technical analysis yielded results for Process Mass Intensity (PMI) of 38.14 and Renewable Material Index (RMI) of 5.09. The minimum process scale for economic feasibility (MPSEF) was 19.6 Ton/h. In this sense, the payback period and turnover ratio were 12 years and 35.01%, respectively. Values of 1.85 kg CO2 eq/kg ethanol for carbon footprint and 1.02 m3/kg ethanol for water depletion were also obtained. For the social analysis, the minimum-to-living wage ratio (M/L) was 1.03. Finally, the sustainability index was 75.19%, and the social and environmental values were the most influential aspects affecting the sustainability index. The results of this work allows a novelty vision related to the integral analysis of sustainability for one of Colombia’s native raw materials, and to propose viable solutions for its use, without threatening food security. Graphical Abstract

Enhancing bioethanol yield from food waste: Integrating decontamination strategies and enzyme dosage optimization for sustainable biofuel production

Amidst the global surge in energy demand, the public’s focus has shifted from fossil fuels to more sustainable and eco-friendly fuels like bioethanol. Thus, the prospect of producing bioethanol from food waste (FW) is gaining traction, offering a sustainable solution to both waste management and energy needs. However, increasing bioethanol yields during food waste fermentation requires an approach that addresses the variability of these heterogeneous feedstocks in terms of chemical composition, microbial contamination, enzyme dosage requirements, and high moisture content. Hence, this study evaluated thermal and chemical decontamination strategies for pre- and post-consumer food waste and minimised the exogenous enzyme dosage by applying an engineered, amylase-producing strain (Saccharomyces cerevisiae ERT12). Results show that thermal sterilisation at an elevated liquefaction temperature significantly improved ethanol yields (from pre-and post-consumer food waste) more than chemical decontamination methods. Also, key findings show that applying the amylase-secreting yeast reduced enzyme dosages by up to 33 %. During fed-batch fermentation with strain ER T12, the highest possible solids loading increased the final ethanol concentrations by 96 % (for pre-consumer FW) and 85 % (for post-consumer FW) compared to batch fermentation. Also, the pre-consumer to post-consumer FW fed-batch fermentation maintained acceptable volumetric production rates of 2.35 to 1.57 g/l.h and yielded 87.6 to 61.2 % of the theoretical maximum. Although the maximum solids loadings, ethanol titres and yields achievable in food waste fermentations were still limited by the inherent moisture contents of the feed, they demonstrated performances that may be appropriate for industrial implementation, considering the negative feedstock costs.

Highly Efficient Production of Cellulosic Ethanol from Poplar Using an Optimal C6/C5 Co-Fermentation Strain of Saccharomyces cerevisiae.

Cellulosic ethanol is the key technology to alleviate the pressure of energy supply and climate change. However, the ethanol production process, which is close to industrial production and has a high saccharification rate and ethanol yield, still needs to be developed. This study demonstrates the effective conversion of poplar wood waste into fuel-grade ethanol. By employing a two-step pretreatment using sodium chlorite (SC)-dilute sulfuric acid (DSA), the raw material achieved a sugar conversion rate exceeding 85% of the theoretical value. Under optimized conditions, brewing yeast co-utilizing C6/C5 enabled a yield of 35 g/L ethanol from 10% solid loading delignified poplar hydrolysate. We increased the solid loading to enhance the final ethanol concentration and optimized both the hydrolysis and fermentation stages. With 20% solid loading delignified poplar hydrolysate, the final ethanol concentration reached 60 g/L, a 71.4% increase from the 10% solid loading. Our work incorporates the pretreatment, enzymatic hydrolysis, and fermentation stages to establish a simple, crude poplar waste fuel ethanol process, expanding the range of feedstocks for second-generation fuel ethanol production.

Pre-adaptation of yeast (Saccharomyces cerevisiae) strains to very high gravity can improve fermentation parameters and reduce osmotic stress

AbstractThis study investigated improvements in sugarcane ethanol production by adapting yeast strains for very high gravity fermentation. Two yeast strains (C22 and Y904) were adapted in eight fermentation cycles with increasing initial sugar content from 56.2 to 296.1 g L−1(Experiment 1). After the last cycle, the “adapted” yeasts were recycled in a wort containing 296.1 g L−1initial sugar and compared with their respective strains that were not subjected to the adaptation process (Experiment 2). Fermentative parameters were analyzed and the osmotic stress on yeast cell morphology was assessed by scanning electron microscopy (SEM). In Experiment 1, along the fermentation cycles, strain Y904 showed a decrease in cell viability after sugar concentration of 223 g L−1. SEM images showed that Y904 cells were wrinkled after this cycle. In the case of strain C22, no differences in cell viability were observed along the cycles. However, for both strains, the residual sugars were relatively high and the ethanol content was below the maximum potential. In Experiment 2, for strain Y904, no differences were observed between adapted and non-adapted yeasts in terms of ethanol content, cell viability, and morphology. In the case of strain C22, cell viability and final ethanol content were significantly higher in the adapted yeast, which had cells less damaged by the osmotic stress. In conclusion, the study supports the importance of yeast strain selection and adaptation for efficient VHG fermentation, by demonstrating the superior performance of yeast strain C22 in response to increasing initial sugar content.

Optimization of beer mixed fermentation using Saccharomyces cerevisiae and Lactobacillus brevis

Mixed fermentation is one of the methods used in sour beer production. The process requires initialization of the fermentation step by well-planned addition of brewing yeast and lactic acid bacteria to slightly hopped wort. The final product’s properties strictly depend on how the microorganisms are pitched and the initial wort composition. The experiment was performed to evaluate the impact of different initial conditions and pitching methods on the mixed fermentation process and the final product’s characteristics. With the aim of limitation of the number of experiments, the Box–Behnken design was applied. Three independent factors were considered while obtaining the response surface: initial extract, bitterness and order of pitching. The final product’s properties: ethanol and lactic acid concentration, appeared to depend strictly on initial conditions and pitching order. Several important observations have been made; for example, it appeared that the presence of LAB does not significantly impact the final ethanol concentration. Optimal conditions for obtaining the maximum or minimum of each quality were calculated using Matlab. Obtained results might improve the sour beer production process while shortening the duration and reducing the usage of ingredients.

Adapted feeding strategies in fed-batch fermentation improve sugar delivery and ethanol productivity

ABSTRACTBioethanol is a renewable fuel widely used in road transportation and is generally regarded as a clean energy source. Although fermentation is one of the major processes in bioethanol production, studies on improving its efficiency through operational design are limited, especially compared to other steps (pretreatment and hydrolysis/saccharification). In this study, two adapted feeding strategies, in which feed medium addition (sugar delivery) was adjusted to increase the supply of fermentable sugar, were developed to improve ethanol productivity in 5-L fed-batch fermentation by Saccharomyces cerevisiae. Specifically, a linear adapted feeding strategy was established based on changes in cell biomass, and an exponential adapted feeding strategy was developed based on cell biomass accumulation. By implementing these two feeding strategies, the overall ethanol productivity reached 0.88±0.04 and 0.87±0.06 g/L/h, respectively. This corresponded to ~20% increases in ethanol productivity compared to fixed pulsed feeding operations. Additionally, there was no residual glucose at the end of fermentation, and final ethanol content reached 95±3 g/L under the linear adapted operation and 104±3 g/L under the exponential adapted feeding strategy. No statistical difference was observed in the overall ethanol yield (ethanol-to-sugar ratio) between fixed and adapted feeding strategies (~91%). These results demonstrate that sugar delivery controlled by adapted feeding strategies was more efficient than fixed feeding operations, leading to higher ethanol productivity. Overall, this study provides novel adapted feeding strategies to improve sugar delivery and ethanol productivity. Integration into the current practices of the ethanol industry could improve productivity and reduce production costs of fermentation processes.

Cannabis-based biofuels in a biorefinery approach

Cannabis cultivation has been growing worldwide due to the legalization for either or both medicinal and recreational uses. Therefore, the amount of agriculture residues for this crop has the potential to become a promising feedstock for biofuels. This study aimed to demonstrate the complete valorization of cannabis biomass residues for biofuel production. Through the optimization of acid hydrolysis operation parameters (2:1 acid-to-biomass ratio, 60 min of swelling and 60 min of post-hydrolysis), it was possible to keep high glucose yields and low inhibitor formation. The use of CaCO3 to neutralize the cannabis hydrolysate allowed the fermentation with a final ethanol concentration of 30 gEtOH/100 gbiomass. After distillation, the vinasse was used to produce biogas (270 L CH4/kg VS). Therefore, a two-step acid hydrolysis can be considered as an efficient pretreatment for cannabis biomass to be used for the combined production of bioethanol and biogas.

Development of two devices for high-throughput screening of ethanol-producing microorganisms by real-time CO2 production monitoring.

Bioethanol's importance as a renewable energy carrier led to the development of new devices for the high-throughput screening (HTS) of ethanol-producing microorganisms, monitoring ethanol production, and process optimization. This study developed two devices based on measuring CO2 evolution (an equimolar byproduct of microbial ethanol fermentation) to allow for a fast and robust HTS of ethanol-producing microorganisms for industrial purposes. First, a pH-based system for identifying ethanol producers (Ethanol-HTS) was established in a 96-well plate format where CO2 emission is captured by a 3D-printed silicone lid and transferred from the fermentation well to a reagent containing bromothymol blue as a pH indicator. Second, a self-made CO2 flow meter (CFM) was developed as a lab-scale tool for real-time quantification of ethanol production. This CFM contains four chambers to simultaneously apply different fermentation treatments while LCD and serial ports allow fast and easy data transfer. Applying ethanol-HTS with various yeast concentrations and yeast strains displayed different colors, from dark blue to dark and light green, based on the amount of carbonic acid formed. The results of the CFM device revealed a fermentation profile. The curve of CO2 production flow among six replications showed the same pattern in all batches. The comparison of final ethanol concentrations calculated based on CO2 flow by the CFM device with the GC analysis showed 3% difference which is not significant. Data validation of both devices demonstrated their applicability for screening novel bioethanol-producer strains, determining carbohydrate fermentation profiles, and monitoring ethanol production in real time.

Brewing a Craft Belgian-Style Pale Ale Using Pichia kudriavzevii 4A as a Starter Culture.

There is an expanding market for beer of different flavors. This study aimed to prepare a craft Belgian-style pale ale with a non-Saccharomyces yeast. Pichia kudriavzevii 4A was used as a sole starter culture, and malted barley as the only substrate. The ingredients and brewing process were carefully monitored to ensure the quality and innocuousness of the beverage. During fermentation, the yeast consumed 89.7% of total sugars and produced 13.8% v/v of ethanol. The product was fermented and then aged for 8 days, adjusted to 5% v/v alcohol, and analyzed. There were no traces of mycotoxins, lead, arsenic, methanol, or microbiological contamination that would compromise consumer health. According to the physicochemical analysis, the final ethanol concentration (5.2% v/v) and other characteristics complied with national and international guidelines. The ethyl acetate and isoamyl alcohol present are known to confer sweet and fruity flavors. The sensory test defined the beverage as refreshing and as having an apple and pear flavor, a banana aroma, and a good level of bitterness. The judges preferred it over a commercial reference sample of Belgian-style pale ale made from S. cerevisiae. Hence, P. kudriavzevii 4A has the potential for use in the beer industry.

Effects of Sorghum Grain and Wort Composition on Dry Grind Fermentation Performance: A Model for Baijiu Production

Sorghum grain is the principal raw material for Baijiu production, but the effects of grain and wort composition on fermentation performance are unclear. Ethanol production at laboratory scale using grains of 11 commercial sorghum cultivars from a field trial was investigated using dry grind fermentation. Initial wort glucose content was 141–150 g/L and fermentability (glucose-to-ethanol conversion rate) was 87–90%. Ethanol production rate among sorghum genotypes ranged from 1.18 to 2.04 mL of ethanol per litre wort per hour of fermentation. The cultivars were categorised into four groups according to a fermentation endpoint of 60–69 h, 70–79 h, 80–89 h and >90 h. All but one of the sorghums produced a final ethanol content of 9.47–9.76% v/v. Cultivars with high-starch and low-protein grains were the most suitable for fermentation due to the high final ethanol content and fermentability achieved. Initial wort glucose content and yeast assimilable nitrogen content were not correlated with grain starch content, protein content, ethanol content, fermentability, ethanol production rate or glucose consumption rate. Knowledge of the effects of sorghum grain quality on fermentation performance can pave the way for further research to optimise solid-state fermentation for Baijiu production.

Development of colloidal lignin particles through particle design strategies and screening of their Pickering stabilizing potential

Colloidal lignin particles (CLPs) have increased interest as green and sustainable materials for Pickering stabilizers, with particle design being an important step towards their effective use. In this context, the antisolvent precipitation method was selected to conduct a study aiming at understanding the effect of process variables (initial lignin concentration, antisolvent pH, final ethanol concentration, and antisolvent addition rate) on particle size, zeta potential, color parameters, and contact angle. Moreover, their Pickering stabilizing potential was preliminarily screened. The evaluation using a Fractional Factorial Design revealed that the particle size is significantly influenced by the initial lignin concentration (as it increases, larger particles are obtained) and the final ethanol concentration (as it increases, smaller sizes result). The zeta potential is significantly affected by the antisolvent pH and the initial lignin concentration; the increase in both parameters results in higher negative values. The color is significantly dependent on the used initial lignin concentration (as it increases, particles become lighter and the yellowish accentuates) and the antisolvent pH (as it increases, particles become darker). Both initial lignin concentration and final ethanol concentration increase promote hydrophobicity, whereas increasing the antisolvent pH and its addition rate turns particles more hydrophilic. Through this strategy, it was possible to achieve CLPs with promising Pickering stabilizing potential, putting in evidence the importance of understanding the production process to design effective particles for target applications.

Fermentation of Sweet Sorghum (Sorghum bicolor L. Moench) Using Immobilized Yeast (Saccharomyces cerevisiae) Entrapped in Calcium Alginate Beads

As the population grows, there is a need to address the continuous depletion of non-renewable energy sources and their negative effects on the environment. This led to a substantial assessment of possible innovations and raw materials to increase the volumetric productivity of alternative fuels to supply the energy needed worldwide. In addition to its environment-friendly properties, a biofuel derived from plant-based sources is also a sustainable material. For high ethanol production from plant-based biofuel, several techniques have been developed, including cell or enzyme immobilization. The key purposes of utilizing immobilized cells or enzymes are to improve bioreactor yield with upgraded enzyme establishment and to increase enzyme utilization. The fermentation of sweet sorghum extract to produce ethanol was conducted in this study, and it was found that the optimum sodium alginate concentration for immobilizing yeast is 3% w/v. It was also found that the free yeast has a shorter optimum fermentation period which is four days (96 h), in comparison with the immobilized yeast, which is five days (120 h). The immobilized yeast has a higher ethanol concentration produced and percent conversion compared to the free yeast. The immobilized yeast entrapped in calcium alginate beads permitted ten five-day (120 h) reuse cycles which are still in stable final ethanol concentration and percent conversion. Due to a lack of experimental support in the necessary condition (optimum level of the number of fermentation days and the concentration of sodium alginate) for the optimal ethanol yield from the extract of sweet sorghum, this study was conducted. This study also tried to address the global demand for ethanol by specifying the optimum conditions necessary for efficient fermentation, specifically for ethanol production using an extract from sweet sorghum. Furthermore, this experimental work serves as a basis for further investigations concerning ethanol production from Agri-based materials, such as sweet sorghum.

Combined Use of Schizosaccharomyces pombe and a Lachancea thermotolerans Strain with a High Malic Acid Consumption Ability for Wine Production

The development of new fermentative strategies exploiting the potential of different wine-related species is of great interest for new winemaking conditions and consumer preferences. One of the most promising non-conventional approaches to wine fermentation is the combined use of deacidifying and acidifying yeasts. Lachancea thermotolerans shows several other properties besides lactic acid production; among them, high malic acid consumption is of great interest in the production of red wines for avoiding undesirable refermentations once bottled. The combination of a L. thermotolerans strain that is able to consume malic acid with a Schizosaccharomyces pombe strain helps to ensure malic acid elimination during alcoholic fermentation while increasing the final acidity by lactic acid production. To properly assess the influence of this alternative strategy, we developed combined fermentations between specific strains of L. thermotolerans and S. pombe under sequential inoculation. Both species showed a great performance under the studied conditions, influencing not only the acidity but also the aromatic compound profiles of the resulting wines. The new proposed biotechnological strategy reduced the final concentrations of ethanol, malic acid and succinic acid, while it increased the concentrations of lactic acid and esters.

Impacts of Reduced (Vacuum) Pressure on Yeast Fermentation as Assessed Using Standard Methods and Automated Image Analysis

In this study the combinatory effect of several extrinsic factors on reduced (vacuum) pressure fermentations was explored. Specifically, the pressure, temperature, and FAN levels of high gravity Saccharomyces cerevisiae fermentations were manipulated, while yeast morphology was assessed using automated multivariate image analysis. Fermentation attributes including yeast growth, viability, and ethanol production were monitored using standard methods. Across all FAN and temperature levels, reduced pressure (vacuum pressure) fermentations resulted in a greater than or equal number of cells in suspension, higher average viability, and greater ethanol production in comparison to atmospheric pressure fermentations; however, the magnitude of the effect varied with extrinsic factors. The image analysis revealed that while yeast size was extremely variable across all fermentations, the ratio of vacuole to cell area consistently decreased over each fermentation and could be used to predict the point where the yeast experienced a sharp decline in viability ending the fermentation. This study showed that a combination of traditional measurements and novel automated analyses can be used by brewers to anticipate performance and endpoints of their fermentations, and that reduced pressure can have significant effects upon the rate and final ethanol concentration of variable industrial fermentations.

Characterization of Nero Antico di Pretalucente Wine and Grape Fungal Microbiota: An Expression of Abruzzo Region Cultivar Heritage

The aim of this study was to characterize the ampelographic and genetic profiles of Vitis vinifera L. cv. Nero Antico di Pretalucente and to describe the grape-borne fungal communities. The oenological characteristics and the aroma profile of wine obtained by spontaneous fermentation were also investigated. Microsatellite profiles and ampelographic traits indicated that this cultivar presented a unique profile, and therefore it can be considered a cultivar in its own right and autochthonous of Gessopalena village. Next-generation sequencing analysis revealed that Aureobasidium spp. was the main genus detected on grapes. At the species level, Aureobasidium pullulans was the main species, followed by Alternaria alternata. Wines were characterized by a final ethanol content of 12.75% (v/v), a pH of 3.4, a volatile acidity lower than 0.6 g/L, a content of glycerol of 8.56 g/L, and a concentration of polyphenols and anthocyanins of 977 GAE/L and 266 mg/L, respectively. The intensity and tonality of the wine as well as the active odor compounds found were described. The results obtained could improve the knowledge concerning the agronomic traits and the wine obtained from this ancient and autochthonous grapevine variety cultivated in a foothill area, in order to offer consumers a wine with unique traits.

Rheological behaviors of ethanol-fractional polysaccharides from Dendrobium officinale in aqueous solution: Effects of concentration, temperature, pH, and metal ions

Ethanol fractional precipitation is an important technology to classify polysaccharides at different molecular weights. In this study, polysaccharides of Dendrobium officinale were step-precipitated by final ethanol concentrations of 40%, 60% and 80%, named as EPDO-40, EPDO-60 and EPDO-80, respectively. Chemical composition, molecule weights and monosaccharides were identified. Effects of concentration, temperature, pH and metal ions on rheological properties were investigated. Results showed that all EPDOs behaved as non-Newtonian fluid in a certain shear rate range of 0.1–1000 s−1 which is affected by their different chemical characteristics. Viscosities of all polysaccharides showed a concentration dependent manner, and they decreased with the increased temperatures from 10 to 90 °C. Viscosities of EPDO-40 and EPDO-80 increased at a range of lower pH significantly, while that of EPDO-60 decreased. Na+, K+, Mg2+ and Ca2+ could all affect the viscosity of EPDOs but in different patterns. Accordingly, it demonstrated that EPDOs with different chemical characteristics had different rheological properties, which could be applied more accurately in foods industry.

Preparation of nanocellulose crystal from bleached pulp with an engineering cellulase and co-production of ethanol

The study investigated the feasibility of co-production of nanocellulose crystal (CNC) and ethanol using the bleached pine kraft pulp (BPKP) as a substrate by enzymatic hydrolysis. An engineering strain Penicillum oxalicum cEES-XM was constructed to produce suitable cellulase used in enzymatic hydrolysis of BPKP for preparing CNC. The cellulase from Trichoderma reesei SCB18 was used for simultaneous saccharification and fermentation of residues and hydrolysates from enzymatic hydrolysis for producing ethanol. The result showed that the CNC yield reached 7.35 % (w/w) by hydrolysis at 10 % solid content, and the final ethanol concentration was 13.27 mg/mL in fermentation liquor. Using SEM, XRD, TGA, and DLS methods, the characteristics of CNC including, morphology, crystallinity, thermal stability and particle size distribution, were also examined. This work provided a reference for realizing high-efficient application of cellulose in the pulp.

Ethanol-lactate transition of Lachancea thermotolerans is linked to nitrogen metabolism

Climate change increases sugar content in grapes, resulting in unwanted increase in ethanol content of wine. Lachancea thermotolerans ferments glucose and fructose into both ethanol and lactate, decreasing final ethanol content and positively affecting wine acidity. Reported Lachancea thermotolerans strains show big variation in lactate production during fermentation. However, a mechanistic understanding of this lactate producing phenotype is currently lacking. Through a combination of metabolomics, transcriptomics, genomics and computational methods we show that the lactate production is induced by amino acid limitation in a high lactate producing strain. We found in fermentations in synthetic grape juice media that lactate production starts in the last stages of growth, marked by decreased growth rate and increased expression levels of stress related genes. This onset of lactate production is specific for the high lactate producing strain and independent of oxygen availability. The onset of lactate production was changed by increased amino acid content of the media, and it is shown by both computational methods and amino acid measurements that at the onset of lactate production amino acids become limiting for growth. This study shows that lactate production of Lachancea thermotolerans is directly linked to nitrogen availability in the media, an insight that can further aid in the improvement of wine quality.