This paper studied the fermentation rules of apple cider vinegar from fruit juice,to provide a theoretical guidance for the production of apple cider vinegar.Using Fuji apples as raw materials,the process parameters(f...This paper studied the fermentation rules of apple cider vinegar from fruit juice,to provide a theoretical guidance for the production of apple cider vinegar.Using Fuji apples as raw materials,the process parameters(fermentation temperature,fermentation time,stirring speed,and inoculation amount)of apple cider vinegar fermentation were optimized through single-factor experiments and response surface analysis.The results indicated that the fermentation temperature had no significant effect on the total acid content of apple cider vinegar fermentation,the fermentation time had an extremely significant effect on the total acid content of apple cider vinegar fermentation,and the stirring speed and inoculation amount had a significant effect on the total acid content of apple cider vinegar fermentation.Through process optimization,the optimal process parameters for apple cider vinegar fermentation are fermentation temperature of 33℃,fermentation time of 39 h,stirring speed of 1500 r/min,and acetic acid bacteria inoculation amount of 7%.Under such conditions,the total acid content of fermented apple cider vinegar is 62.22 g/L,very close to the predicted value of the model,indicating that the process parameters of acetic acid fermentation obtained by response surface methodology(RSM)optimization are reliable and can be used for actual production prediction.展开更多
Vinegars are commonly used as food condiments and preservatives. Apple cider vinegar (ACV) is also used in the Ayurvedic pharmaceutical industry because of its medicinal properties. Since specifically selected starter...Vinegars are commonly used as food condiments and preservatives. Apple cider vinegar (ACV) is also used in the Ayurvedic pharmaceutical industry because of its medicinal properties. Since specifically selected starter cultures for commercial vinegar production are not readily available, apple juice supplemented with sugar is commonly inoculated with a microbiologically undefined culture obtained from the previous batch of ACV. The present work focuses on the isolation of yeasts and acetic acid bacteria from ACV and the preparation of a starter culture. ACV was produced in a bench scale bioreactor using a traditional fermentation process wherein an acetic acid concentration of 3.8% was obtained after three weeks. Several acetic acid bacteria (AAB) were isolated from ACV using selective media. Microscopy revealed the cultures to be gram negative to gram variable short rods. The growth pattern of the isolates on differential media and biochemical tests suggested the presence of Acetobacter and Gluconobacter species. Ten potent isolates were selected for starter culture preparation. Two consortia were formulated with five AAB isolates in each along with a yeast isolate and used for ACV production, wherein an acetic acid concentration of 4.2% - 4.9% was obtained in 10 - 12 days. Thus, these two starter cultures with locally isolated AAB can be used for the commercial production of apple cider vinegar.展开更多
This study was designed to assess the effect to apple cider vinegar (ACV) on oxidative stress biomarkers in male and female Wistar rats exposed to chronic restraint stress. Severe and persistent stress elevates reacti...This study was designed to assess the effect to apple cider vinegar (ACV) on oxidative stress biomarkers in male and female Wistar rats exposed to chronic restraint stress. Severe and persistent stress elevates reactive oxygen species (ROS) production by metabolic and physiological processes;causing cellular damage. Thirty (30) Adult Wistar rats of both sexes weighing about 150 - 200 g were divided into 3 groups each consisting of a male and female subgroup and given the following treatments once a day for 21 days: Normal control group received 0.5 ml distilled water orally, the restraint stress (RS) group was exposed to chronic restraint stress 6 hours daily while the Apple cider vinegar (ACV)-treated group received 4 ml/kg of apple cider vinegar orally in addition to chronic restraint stress 6 hours daily. The rats were sacrificed after the experimental period and blood was collected via cardiac puncture for assessing oxidative stress biomarkers. ACV (4 ml/kg) treatment decreased lipid peroxidation (MDA) and serum catalase (CAT) activity while upregulating endogenous superoxide dismutase (SOD) activity. The findings of this study show that the female Wistar rats are more predisposed to the antioxidant effect of ACV than the males.展开更多
Response surface methodology (RSM) was applied to provide predictive models for optimisation of extraction of selected polyphenolic compounds from cider apple pomace under aqueous acetone. The design of experiment (Do...Response surface methodology (RSM) was applied to provide predictive models for optimisation of extraction of selected polyphenolic compounds from cider apple pomace under aqueous acetone. The design of experiment (DoE) was conducted to evaluate the influence of acetone concentration % (v/v), solid-to solvent ratio % (w/v), temperature (˚C) and extraction time (min) and their interaction on phenolic contents, using the Central Composite Rotatable Design (CCRD). The experimental data were analysed to fit statistical models for recovery of phenolic compounds. The selected models were significant (P 0.05), except for Chlorogenic acid and Quercetin 3-glucoside which had significant lack of fits (P R2 > 0.9000 and adjusted? ?reasonable agrees with predicted . Coefficient of variation < 5% for each determination at the 95% confidence interval. These models could be relied upon to achieve optimal concentrations of polyphenolic compounds for applications in nutraceutical, pharmaceutical and cosmetic industries.展开更多
As a practicing physician and professor of medicine, I am asked about the benefits of drinking apple cider vinegar (苹果醋)all the time.I 1 those moments, because we can talk with delight about the history of vinegar,...As a practicing physician and professor of medicine, I am asked about the benefits of drinking apple cider vinegar (苹果醋)all the time.I 1 those moments, because we can talk with delight about the history of vinegar, and 2 it can possibly benefit them.Historically, vinegar has been used for many 3. A few examples are that of the famous Greek physician Hippocrates, who recommended vinegar for the 4 of cough and colds.展开更多
This study investigated the impact of two yeast strains,Saccharomyces cerevisiae(SC)and Torulaspora delbrueckii(TD),on the chemical composition of ciders prepared from the juices of six traditional apple cultivars gro...This study investigated the impact of two yeast strains,Saccharomyces cerevisiae(SC)and Torulaspora delbrueckii(TD),on the chemical composition of ciders prepared from the juices of six traditional apple cultivars grown in Finland,aiming to evaluate the potential of these underutilized local cultivars for cider production.Sugars,organic acids and ethanol contents were analyzed using gas chromatography coupled with a flame ionization detector(GC-FID),while volatile compounds were identified and semi-quantified using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-CG-MS).Apple cultivar se-lection had a stronger impact than yeast strain on the sugars and organic acids in ciders,whereas both factors shaped the volatile compound profiles.Among the cultivars,‘Rambo’demonstrated the greatest potential for cider aroma development.Specifically,fermentation of‘Rambo’juice with TD yielded the highest ester pro-duction among all TD-fermented ciders.Volatile profiling further revealed that TD favored the formation of fruity esters while reducing higher alcohol and acetic acid levels,resulting in potentially more complex and fruity aroma,compared to SC.Other cultivar-yeast combinations,such as‘Aleksanteri’,‘Antonovka’,or‘Mustialan Iso Ven¨al¨ainen’with SC,could also enhance cider aroma complexity.These findings highlight the potential of underutilized apple cultivars,when combined with tailored yeast selection,to diversify cider profiles and to enhance sensory quality.展开更多
During the natural fermentation of fruit wine,different yeast strains with specific fermentation characteristics and metabolic processes have an important influence on the quality and flavor complexity of fruit wines....During the natural fermentation of fruit wine,different yeast strains with specific fermentation characteristics and metabolic processes have an important influence on the quality and flavor complexity of fruit wines.Rhodotorula mucilaginosa is a non-Saccharomyces yeast species with low fermentation activity.It is typically involved in the first stage of fruit wine fermentation and is commonly isolated from apple and grape orchards.This investigation evaluated the effect of simultaneous and sequential fermentations of Saccharomyces cerevisiae CGMCC 2.3854 and two selected indigenous R.mucilaginosa strains on the fermentation process,quality,and flavor profile of ciders.Results showed that mixed fermentation enhanced the brightness,altered the organic acids content,and improved the clarity and flavor complexity of the ciders.Compared to Sc cider,Rh-Sc cider showed significantly higher ABTS and DPPH free radical scavenging activities.In particular,Rh-Sc cider had the highest acetate esters content,in which both isoamyl acetate(313.69±29.56μg/L)and phenethyl acetate(115.82±9.02μg/L)were significantly higher than those of other ciders,which enhanced the fruity and floral notes.Moreover,Rh-Sc cider showed the highest overall sensory quality.This investigation provides an effective strategy for enhancing the sensory and flavor complexity of cider through the simultaneous fermentation of Rh and Sc.展开更多
Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and l...Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and lipase activities that release aroma precursors,yet its interaction with Saccharomyces cerevisiae has not been well characterized.This study evaluated sequential inoculation of M.koreensis and S.cerevisiae with 0 h,24 h,and 48 h delays.A 48-h delay(SM48)extended M.koreensis viability to 9 days,increased ethanol production,and produced sensory attributes characterized by lower sourness and astringency and higher umami and richness.The SM48 group produced the most abundant and diverse volatile compounds,with key fruity and floral esters elevated.OPLS-DA identified these esters as major discriminant contributors,whereas compounds commonly associated with off-flavors such as acetic acid and hexanal were reduced.Metabolic pathway analysis indicated enhanced Ehrlich and esterification pathways with reduced acetate production.Multi-method validation supported that SM48 cider exhibits more complex volatile profiles,stronger fruity and floral notes,and improved color.These results demonstrate that controlled sequential inoculation is an effective approach for improving cider aroma complexity and overall product quality.展开更多
In this study,the first fermentation of Fuji apple juice was carried out using Saccharomyces cerevisiae WLS21 and continued a second fermentation using S.cerevisiae HYJ1,HYJ2,PE2,and Y41 in sealed bottles after adjust...In this study,the first fermentation of Fuji apple juice was carried out using Saccharomyces cerevisiae WLS21 and continued a second fermentation using S.cerevisiae HYJ1,HYJ2,PE2,and Y41 in sealed bottles after adjusting the sugar level.The physicochemical indexes,aromas,and sensory characteristics of four sparkling ciders were analyzed.The results revealed that HYJ2 produced the highest amount of ethanol and Y41 had the highest pressure in the bottle at the end of fermentation.Y41 produced the highest citric and succinic acids and HYJ1 produced higher fumaric acid and total volatiles.HYJ1 cider had an obvious herbaceous odor,and Y41 cider had a fruity character.Sixty-seven volatiles were detected from four sparkling ciders(55 fermentative and 12 non-fermentative aromas).Esters(EEFAs and HAAs)were the main volatile aroma family produced during secondary fermentation,and terpenes contributed the most to fruity odor.Based on univariate(ANOVA)and multivariate analysis of variance(PLS-DA)screening of four cider significant variables,13 volatiles with variable predictive importance(VIP)≥1 were identified.PLSR analysis revealed that 2-methylbutyl acetate,ethyl heptanoate,2-methyl-1-butanol,nonanal,2-nonanone,β-damascenone,and linalool were potential volatile markers for OAV>1.展开更多
The production of sparkling cider could intercept the needs of non-habitual consumers of this alcoholic-beverage.This investigation was aimed to develop procedures for the production of sparkling ciders using the Ital...The production of sparkling cider could intercept the needs of non-habitual consumers of this alcoholic-beverage.This investigation was aimed to develop procedures for the production of sparkling ciders using the Italian apple variety‘Limoncella’by application of both Champenoise and Charmat methods.First of all,the authors apply a chemometric approach to evaluate the effects of duration of the pectolytic treatment carried out on crushed apples and of the sugar added before refermentation on physicochemical,and sensory characteristics of the Champenoise sparkling ciders.The pectolytic treatment was able to influence colour,alcohol,pH,bitterness(higher when the treatment was shorter),titratable and volatile acidity,soluble solids,CO_(2),total phenolics,sweetness,saltiness,bitterness,and volatile alcohols(higher when the treatment was longer).The addition of sugar increased alcohol,soluble solids,and CO_(2),and decreased the production of volatile compounds.Then,the effects of the refermentation methods(Champenoise or Charmat)on the same parameters were evaluated.Charmat and Champenoise sparkling ciders differed for parameters showing higher values in the second type,i.e.colour(9.982 and 14.296 SRM),organic acid concentrations,CO_(2)(6.35 and 7.55 g/L),phenolic(313 and 424 mg/L)and volatile content,foam persistence(2.2 and 3.8),and saltiness(2.1 and 3.2)--and for some sensory attributes such as taste quality and harmony that received higher scores in Charmat sparkling ciders(4.9±0.7 and 4.9±0.0,respectively)than the Champenoise ciders(3.7±0.5 and 3.7±0.4,respectively).Several esters,alcohols,terpenes,acids,phenols,and norisoprenoids had odour activity values>1.Principal Component Analysis(PCA)was able to homogeneously group Champenoise ciders based on the duration of the pectolytic treatment and the addition of sugar before fermentation.PCA was also able to distinguish sparkling ciders by refermentation methods.The results indicated that the chemometric approach is a sensitive tool to monitor the quality and authenticity of local sparkling cider productions.The reduction of the pectolytic treatment time was critical to avoid dramatic increases of lactic acid content.The Champenoise method preserved the cider phenolic content but negatively affected their sensory quality.展开更多
基金Supported by Industrial Promotion Project of Shandong Science and Technology Park in 2017(2017YQ016).
文摘This paper studied the fermentation rules of apple cider vinegar from fruit juice,to provide a theoretical guidance for the production of apple cider vinegar.Using Fuji apples as raw materials,the process parameters(fermentation temperature,fermentation time,stirring speed,and inoculation amount)of apple cider vinegar fermentation were optimized through single-factor experiments and response surface analysis.The results indicated that the fermentation temperature had no significant effect on the total acid content of apple cider vinegar fermentation,the fermentation time had an extremely significant effect on the total acid content of apple cider vinegar fermentation,and the stirring speed and inoculation amount had a significant effect on the total acid content of apple cider vinegar fermentation.Through process optimization,the optimal process parameters for apple cider vinegar fermentation are fermentation temperature of 33℃,fermentation time of 39 h,stirring speed of 1500 r/min,and acetic acid bacteria inoculation amount of 7%.Under such conditions,the total acid content of fermented apple cider vinegar is 62.22 g/L,very close to the predicted value of the model,indicating that the process parameters of acetic acid fermentation obtained by response surface methodology(RSM)optimization are reliable and can be used for actual production prediction.
文摘Vinegars are commonly used as food condiments and preservatives. Apple cider vinegar (ACV) is also used in the Ayurvedic pharmaceutical industry because of its medicinal properties. Since specifically selected starter cultures for commercial vinegar production are not readily available, apple juice supplemented with sugar is commonly inoculated with a microbiologically undefined culture obtained from the previous batch of ACV. The present work focuses on the isolation of yeasts and acetic acid bacteria from ACV and the preparation of a starter culture. ACV was produced in a bench scale bioreactor using a traditional fermentation process wherein an acetic acid concentration of 3.8% was obtained after three weeks. Several acetic acid bacteria (AAB) were isolated from ACV using selective media. Microscopy revealed the cultures to be gram negative to gram variable short rods. The growth pattern of the isolates on differential media and biochemical tests suggested the presence of Acetobacter and Gluconobacter species. Ten potent isolates were selected for starter culture preparation. Two consortia were formulated with five AAB isolates in each along with a yeast isolate and used for ACV production, wherein an acetic acid concentration of 4.2% - 4.9% was obtained in 10 - 12 days. Thus, these two starter cultures with locally isolated AAB can be used for the commercial production of apple cider vinegar.
文摘This study was designed to assess the effect to apple cider vinegar (ACV) on oxidative stress biomarkers in male and female Wistar rats exposed to chronic restraint stress. Severe and persistent stress elevates reactive oxygen species (ROS) production by metabolic and physiological processes;causing cellular damage. Thirty (30) Adult Wistar rats of both sexes weighing about 150 - 200 g were divided into 3 groups each consisting of a male and female subgroup and given the following treatments once a day for 21 days: Normal control group received 0.5 ml distilled water orally, the restraint stress (RS) group was exposed to chronic restraint stress 6 hours daily while the Apple cider vinegar (ACV)-treated group received 4 ml/kg of apple cider vinegar orally in addition to chronic restraint stress 6 hours daily. The rats were sacrificed after the experimental period and blood was collected via cardiac puncture for assessing oxidative stress biomarkers. ACV (4 ml/kg) treatment decreased lipid peroxidation (MDA) and serum catalase (CAT) activity while upregulating endogenous superoxide dismutase (SOD) activity. The findings of this study show that the female Wistar rats are more predisposed to the antioxidant effect of ACV than the males.
文摘Response surface methodology (RSM) was applied to provide predictive models for optimisation of extraction of selected polyphenolic compounds from cider apple pomace under aqueous acetone. The design of experiment (DoE) was conducted to evaluate the influence of acetone concentration % (v/v), solid-to solvent ratio % (w/v), temperature (˚C) and extraction time (min) and their interaction on phenolic contents, using the Central Composite Rotatable Design (CCRD). The experimental data were analysed to fit statistical models for recovery of phenolic compounds. The selected models were significant (P 0.05), except for Chlorogenic acid and Quercetin 3-glucoside which had significant lack of fits (P R2 > 0.9000 and adjusted? ?reasonable agrees with predicted . Coefficient of variation < 5% for each determination at the 95% confidence interval. These models could be relied upon to achieve optimal concentrations of polyphenolic compounds for applications in nutraceutical, pharmaceutical and cosmetic industries.
文摘As a practicing physician and professor of medicine, I am asked about the benefits of drinking apple cider vinegar (苹果醋)all the time.I 1 those moments, because we can talk with delight about the history of vinegar, and 2 it can possibly benefit them.Historically, vinegar has been used for many 3. A few examples are that of the famous Greek physician Hippocrates, who recommended vinegar for the 4 of cough and colds.
基金supported by the Niemi Foundation(award number:20240015)the Lieto Savings Bank Foundation(award number:20240396)+3 种基金Research Council of Finland's research infrastructure funding(Decision No.337980)the European Union-NextGenerationEU instrument funding for the FOODNUTRI National Infrastructure Network(Decision No.345916)the Finland-China Food and Health Network,the China Scholarship Councilthe First division Alar City Science and Technology Project(2024SP01).
文摘This study investigated the impact of two yeast strains,Saccharomyces cerevisiae(SC)and Torulaspora delbrueckii(TD),on the chemical composition of ciders prepared from the juices of six traditional apple cultivars grown in Finland,aiming to evaluate the potential of these underutilized local cultivars for cider production.Sugars,organic acids and ethanol contents were analyzed using gas chromatography coupled with a flame ionization detector(GC-FID),while volatile compounds were identified and semi-quantified using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-CG-MS).Apple cultivar se-lection had a stronger impact than yeast strain on the sugars and organic acids in ciders,whereas both factors shaped the volatile compound profiles.Among the cultivars,‘Rambo’demonstrated the greatest potential for cider aroma development.Specifically,fermentation of‘Rambo’juice with TD yielded the highest ester pro-duction among all TD-fermented ciders.Volatile profiling further revealed that TD favored the formation of fruity esters while reducing higher alcohol and acetic acid levels,resulting in potentially more complex and fruity aroma,compared to SC.Other cultivar-yeast combinations,such as‘Aleksanteri’,‘Antonovka’,or‘Mustialan Iso Ven¨al¨ainen’with SC,could also enhance cider aroma complexity.These findings highlight the potential of underutilized apple cultivars,when combined with tailored yeast selection,to diversify cider profiles and to enhance sensory quality.
基金supported by the Natural Science Foundation of Liaoning Province of China(2023-MS-277).
文摘During the natural fermentation of fruit wine,different yeast strains with specific fermentation characteristics and metabolic processes have an important influence on the quality and flavor complexity of fruit wines.Rhodotorula mucilaginosa is a non-Saccharomyces yeast species with low fermentation activity.It is typically involved in the first stage of fruit wine fermentation and is commonly isolated from apple and grape orchards.This investigation evaluated the effect of simultaneous and sequential fermentations of Saccharomyces cerevisiae CGMCC 2.3854 and two selected indigenous R.mucilaginosa strains on the fermentation process,quality,and flavor profile of ciders.Results showed that mixed fermentation enhanced the brightness,altered the organic acids content,and improved the clarity and flavor complexity of the ciders.Compared to Sc cider,Rh-Sc cider showed significantly higher ABTS and DPPH free radical scavenging activities.In particular,Rh-Sc cider had the highest acetate esters content,in which both isoamyl acetate(313.69±29.56μg/L)and phenethyl acetate(115.82±9.02μg/L)were significantly higher than those of other ciders,which enhanced the fruity and floral notes.Moreover,Rh-Sc cider showed the highest overall sensory quality.This investigation provides an effective strategy for enhancing the sensory and flavor complexity of cider through the simultaneous fermentation of Rh and Sc.
基金financially supported by the National Key Research and Development Project of China[grant number 2023YFD2100304]the Solid-state Fermentation Resources Utilization Key Laboratory of Sichuan Province[grant number 2023GTYY01].
文摘Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and lipase activities that release aroma precursors,yet its interaction with Saccharomyces cerevisiae has not been well characterized.This study evaluated sequential inoculation of M.koreensis and S.cerevisiae with 0 h,24 h,and 48 h delays.A 48-h delay(SM48)extended M.koreensis viability to 9 days,increased ethanol production,and produced sensory attributes characterized by lower sourness and astringency and higher umami and richness.The SM48 group produced the most abundant and diverse volatile compounds,with key fruity and floral esters elevated.OPLS-DA identified these esters as major discriminant contributors,whereas compounds commonly associated with off-flavors such as acetic acid and hexanal were reduced.Metabolic pathway analysis indicated enhanced Ehrlich and esterification pathways with reduced acetate production.Multi-method validation supported that SM48 cider exhibits more complex volatile profiles,stronger fruity and floral notes,and improved color.These results demonstrate that controlled sequential inoculation is an effective approach for improving cider aroma complexity and overall product quality.
基金supported by key agricultural Science and Technology project of Shaanxi Provincial(NYKJ-2019-XA),China.
文摘In this study,the first fermentation of Fuji apple juice was carried out using Saccharomyces cerevisiae WLS21 and continued a second fermentation using S.cerevisiae HYJ1,HYJ2,PE2,and Y41 in sealed bottles after adjusting the sugar level.The physicochemical indexes,aromas,and sensory characteristics of four sparkling ciders were analyzed.The results revealed that HYJ2 produced the highest amount of ethanol and Y41 had the highest pressure in the bottle at the end of fermentation.Y41 produced the highest citric and succinic acids and HYJ1 produced higher fumaric acid and total volatiles.HYJ1 cider had an obvious herbaceous odor,and Y41 cider had a fruity character.Sixty-seven volatiles were detected from four sparkling ciders(55 fermentative and 12 non-fermentative aromas).Esters(EEFAs and HAAs)were the main volatile aroma family produced during secondary fermentation,and terpenes contributed the most to fruity odor.Based on univariate(ANOVA)and multivariate analysis of variance(PLS-DA)screening of four cider significant variables,13 volatiles with variable predictive importance(VIP)≥1 were identified.PLSR analysis revealed that 2-methylbutyl acetate,ethyl heptanoate,2-methyl-1-butanol,nonanal,2-nonanone,β-damascenone,and linalool were potential volatile markers for OAV>1.
基金The manuscript includes results obtained within the project entitled“Valorizzazione della mela Limoncella e melicoltura sostenibile nelle aree rurali dei Monti Dauni”acr.VALMELA funded by PSR PUGLIA 2014/2020-Misura 16-Cooperazione-Sottomisura 16.2-“Sostegno a progetti pilota e allo sviluppo di nuovi prodotti,pratiche,processi e tecnologie”.
文摘The production of sparkling cider could intercept the needs of non-habitual consumers of this alcoholic-beverage.This investigation was aimed to develop procedures for the production of sparkling ciders using the Italian apple variety‘Limoncella’by application of both Champenoise and Charmat methods.First of all,the authors apply a chemometric approach to evaluate the effects of duration of the pectolytic treatment carried out on crushed apples and of the sugar added before refermentation on physicochemical,and sensory characteristics of the Champenoise sparkling ciders.The pectolytic treatment was able to influence colour,alcohol,pH,bitterness(higher when the treatment was shorter),titratable and volatile acidity,soluble solids,CO_(2),total phenolics,sweetness,saltiness,bitterness,and volatile alcohols(higher when the treatment was longer).The addition of sugar increased alcohol,soluble solids,and CO_(2),and decreased the production of volatile compounds.Then,the effects of the refermentation methods(Champenoise or Charmat)on the same parameters were evaluated.Charmat and Champenoise sparkling ciders differed for parameters showing higher values in the second type,i.e.colour(9.982 and 14.296 SRM),organic acid concentrations,CO_(2)(6.35 and 7.55 g/L),phenolic(313 and 424 mg/L)and volatile content,foam persistence(2.2 and 3.8),and saltiness(2.1 and 3.2)--and for some sensory attributes such as taste quality and harmony that received higher scores in Charmat sparkling ciders(4.9±0.7 and 4.9±0.0,respectively)than the Champenoise ciders(3.7±0.5 and 3.7±0.4,respectively).Several esters,alcohols,terpenes,acids,phenols,and norisoprenoids had odour activity values>1.Principal Component Analysis(PCA)was able to homogeneously group Champenoise ciders based on the duration of the pectolytic treatment and the addition of sugar before fermentation.PCA was also able to distinguish sparkling ciders by refermentation methods.The results indicated that the chemometric approach is a sensitive tool to monitor the quality and authenticity of local sparkling cider productions.The reduction of the pectolytic treatment time was critical to avoid dramatic increases of lactic acid content.The Champenoise method preserved the cider phenolic content but negatively affected their sensory quality.
