Impact of two Williopsis yeast strains on the volatile composition of mango wine

The aim of the research was to study the volatile composition of mango wine fermented with two Williopsis yeast strains: Williopsis saturnus var. mrakii NCYC500 and W. staurnus var. suaveolens NCYC2586. Thirty terpenoids, twenty‐six esters, ten alcohols, nine acids, seven aldehydes and ketones, two ethers, two phenols and one sulphur compound were identified in the mango wine fermented with strain NCYC500, while twenty‐seven terpenoids, thirty esters, eleven alcohols, eight acids, eight aldehydes and ketones, three ethers, two phenols, one sulphur compound and one furan were detected in the mango wine fermented with the strain NCYC2586. The kinetic changes, final concentrations and odour activity values of major volatiles were compared between the two Williopsis yeast strains and also with other yeast reported in the literature. The results showed that Williopsis yeast strains NCYC500 and NCYC2586 were high producers of acetic acid and acetate esters, but low producers of medium‐ to long‐chain fatty acids and their corresponding ethyl esters. Unlike mango wine fermented with Saccharomyces cerevisiae, most terpenoids derived from mango juice were retained in the resultant mango wine fermented with the two Williopsis yeast strains, suggesting the mango wine could retain the aromatic hints of fresh mango.     

Effects of branched‐chain amino acid addition on chemical constituents in lychee wine fermented with Saccharomyces cerevisiae

This study investigated the impact of single branched‐chain amino acid addition (L‐valine, L‐leucine, L‐isoleucine) on nonvolatile and volatile constituents in lychee wine fermented with Saccharomyces cerevisiae MERIT.ferm. The individual addition of branched‐chain amino acids decreased the consumption of proline with significantly different rates. The lychee wine with added L‐leucine and L‐isoleucine had higher odour activity values (OAVs) of isoamyl alcohol, active amyl alcohol and isoamyl acetate. The lychee wine with added L‐valine had higher OAVs of isobutyric acid and isobutyl alcohol (5.55 and 2.98, respectively), which were lower in the wine with added L‐leucine (2.91 and 1.02, respectively) or L‐isoleucine (3.43 and 1.73, respectively) relative to the control wine (4.18 and 1.77, respectively), suggesting interactive effects among the amino acids. These findings demonstrated that lychee wine aroma can potentially be manipulated via the addition of selected branched‐chain amino acids.     

不同酿酒酵母菌发酵树莓果酒的理化特性

该研究以秋福树莓为原料,采用五种商业酿酒酵母菌（71B、CECA、VP5、BV818、Montrachet）酿制树莓果酒。实验测定分析了各树莓果酒样品的发酵曲线、理化指标、有机酸及非花色苷单体酚类物质含量,并进行了感官评价。结果表明,菌株VP5启动最为缓慢,菌株71B无明显降酸效果,菌株CECA和BV818感官评分略低,而酿酒酵母Montrachet发酵启动快速,发酵速率平缓,发酵彻底,酒样酒精度高,为9.77%vol;甘油生成能力强,为8.22 g/L;具有较强的降低柠檬酸和苹果酸的能力,且酿酒酵母Montrachet酒样感官评分最高,为43分。单体酚检测结果表明,其总酚含量最高,为21.39 mg/L,其中鞣花酸、没食子酸含量高,黄烷醇类含量居中,这有助于形成树莓果酒鲜艳的色泽,且避免强烈的苦涩感。故酿酒酵母Montrachet适合树莓果酒酿造的优良菌株。     

浅谈冰荔枝酒的生产工艺

介绍了以广东省郁南县成熟荔枝为原料,将鲜荔枝破碎后,经酶解浸渍、果汁澄清、冷冻浓缩、低温发酵、陈酿、调配等工艺酿造出甘甜醇厚、酸甜协调、回味悠长,酒体丰满具有浓郁荔枝果香优质冰荔枝酒。最佳的工艺参数为：酵母加入量为1.5g/L,发酵温度13℃,酒度15%vol～16%vol,总糖260～280g/L,总酸4g/L。     

The effects of grape must fermentation conditions on volatile alcohols and esters formed by Saccharomyces cerevisiae

Changes in aroma compounds synthesised from grape must during fermentation carried out by Saccharomyces cerevisiae, in semi-aerobic, anaerobic, short aeration conditions and after adding ergosterol and oleic acid to the must were studied. The biosynthesis of these aroma compounds was strongly dependent on the fermentation conditions and on the growth of the yeast. Ethanol, isoamyl alcohols, isobutyl alcohol, phenethyl alcohol and isoamyl, butyl and hexyl acetates were produced in greater concentrations in semiaerobic conditions, mainly during cellular growth. 1-Butanol and 1-pentanol were produced in greater levels in anaerobic conditions, when cellular growth was lower. Ergosterol and oleic acid added to the musts generally increased the levels of the aroma compounds in wine compared to those obtained in anaerobic conditions. © 1997 SCI.     

The aromatic volatile composition of Lonicera edulis wines produced with three different strains of Saccharomyces cerevisiae

Three different strains of Saccharomyces cerevisiae – D₁₅, Dibosh and 71B – were evaluated in the fermentation of Lonicera edulis wines. Volatile aromatic components were analysed by gas chromatography–mass spectrometry coupled with headspace solid‐phase microextraction. In all, 81 volatile compounds were identified in L. edulis wines, including 43, 48 and 38 individually found in wines fermented with D₁₅, Dibosh and 71B. There were 17 common volatile aromatic components found in all the three L. edulis wines. The main volatile compounds in wines fermented with D₁₅ and Dibosh yeasts were 2‐methyl‐1‐butanol (24.8%) and hexane (20.6%). Pentanol was the primary volatile aromatic compound in wines produced with S. cerevisiae 71B, accounting for 40.8% of total volatile aromatic compounds. Combining the sensory analysis, S. cerevisiae D₁₅ was suggested to be the most suitable strain for producing L. edulis wine. © 2018 The Institute of Brewing & Distilling     

不同果酒酵母发酵血橙果酒的发酵规律及香气成分的比较

以血橙为原料,比较了两种酵母的发酵规律和发酵的血橙果酒的香气成分,并建立两种酵母的发酵动力模型。结果表明:果酒干酵母起酵时间比果酒酵母1383短;发酵过程中残糖及花色苷逐渐降低,酸度呈先上升后下降的趋势;果酒干酵母及果酒酵母1383酿造的血橙果酒中分别检测出36、39种香气成分,其中相同的香气成分有26种;果酒干酵母和果酒酵母1383的酒精发酵动力方程分别为X=9.3511+26.322e-0.993t和X=9.7201+41.109e-0.093t。      

野生酵母和商品酵母发酵葡萄酒中挥发性成分差异研究

采用顶空固相微萃取（HS-SPME）和气相色谱-质谱联用（GC-MS）技术对5株商品酿酒酵母和7株野生酿酒酵母所酿葡萄酒中的挥发性物质进行分析。结果表明,各葡萄酒中挥发性物质的组成成分相差不大,但在含量上存在差异,野生酿酒酵母所酿造的葡萄酒中主要挥发性物质的总含量要高于商品酿酒酵母。对于葡萄酒中主要由酵母代谢产生的3类挥发性物质—酯类、醇类和酸类,其含量最高的均为用野生酿酒酵母酿造的葡萄酒,其中以W2和W7最为突出。感官分析结果表明,C1、C2和W2的果香、花香较为突出,C4和W2具有明显的草本味,C2和W1的胡椒味较强。      

Evaluation of the volatile profile of wax apple (Syzygium samarangense) wines fermented with different commercial Saccharomyces cerevisiae strains

Food Science and Biotechnology - The effect of four commercial Saccharomyces cerevisiae strains (D254, VIC, BV818, and RV100) on the volatile profile of wax apple (Syzygium samarangense) wine was...     

Evolution of volatile compounds in papaya wine fermented with three Williopsis saturnus yeasts

The changes in volatile compounds during papaya juice fermentation with three Williopsis saturnus yeasts were investigated in this study. Time‐course papaya juice fermentations were carried out using three Williopsis saturnus yeasts: W. saturnus var. mrakii NCYC2251, W. saturnus var. saturnus NCYC22 and W. saturnus var. sargentensis NCYC2727. Changes in yeast cell population, Brix and pH were similar among the three yeasts, which preferentially utilised glucose over fructose while partially degrading l ‐malic acid. A range of volatile compounds were produced during fermentation including fatty acids, alcohols and esters with esters being the most abundant volatile compounds produced. Benzyl isothiocyanate, butyric acid, 2‐ethylhexanol, benzaldehyde and β‐damascenone present in the papaya juice were metabolised to trace levels during fermentation. There were significant variations among the three yeasts in their ability to produce and metabolise volatile compounds during fermentation. The study suggests that papaya juice fermentation with W. saturnus yeasts is able to result in the formation of a more complex aroma compounds.     

Co-inoculation of different Saccharomyces cerevisiae strains and influence on volatile composition of wines

Wine is the result of the performance of different yeast strains throughout the fermentation in both spontaneous and inoculated processes. 22 Saccharomyces cerevisiae strains were characterized by microsatellite fingerprinting, selecting 6 of them to formulate S. cerevisiae mixed cultures. The aim of this study was to ascertain a potential benefit to use mixed cultures to improve wine quality. For this purpose yeasts behavior was studied during co-inoculated fermentations. Aromatic composition of the wines obtained was analyzed, and despite the fact that only one strain dominated at the end of the process, co-cultures released different concentrations of major volatile compounds than single strains, especially higher alcohols and acetaldehydes. Nevertheless, no significant differences were found in the type and quantity of the amino acids assimilated. This study demonstrates that the final wine composition may be modulated and enhanced by using suitable combinations of yeast strains.     

Effects of seven yeast strains on the volatile composition of Palomino wines

The must obtained from Palomino grapes was inoculated with seven different commercial yeast strains (three Saccharomyces cerevisiae cerevisiae– MO5, CEG and IOC BR 8000 and four Saccharomyces cerevisiae bayanus– ALB, KD, REIMS and IOC 2007) and fermented under identical conditions. Standard chemical analyses were done on the final industrial wines and the major volatile compounds extracted and analysed by gas chromatography coupled to mass spectrometry. No differences were found in gross chemical composition, but the wines had significantly different volatile characteristics and the results demonstrated that large sensory differences were generated by the different yeast strain that had been used in the vinification. The major constituents that contributed to the volatile composition in this wine were the higher alcohols, ethyl esters, acetates, fatty acids and volatile phenols. In terms of floral and fruity odours, the best results were obtained for the wines inoculated with IOC 2007, ALB and REIMS S. cer. bayanus strain.     

Growth and fermentation kinetics of a mixed culture of Saccharomyces cerevisiae var. bayanus and Williopsis saturnus var. saturnus at different ratios in longan juice (Dimocarpus longan Lour.)

Cofermentation of longan juice by mixed cultures of Saccharomyces cerevisiae var. bayanus EC‐1118 and Williopsis saturnus var. saturnus CBS254 at two inoculation ratios (EC‐1118:CBS254 = 1:100 and 1:1000 cfu mL^?1) was performed to ascertain their impact on longan wine aroma compound formation. The results showed improved aroma compound profiles in the longan wine fermented with mixed yeasts in comparison with the longan wines fermented with single yeasts in terms of increased production of acetate esters, fatty acid ethyl esters, alcohols and carboxylic acids. The impact of cofermentation on longan wine aroma formation was affected by the ratio of S. cerevisiae EC‐1118 to W. saturnus CBS254 with 1:100 cfu mL^?1 being more effective. This research suggests that the inoculation ratio of mixed yeasts may be used as an effective means of manipulating longan wine aroma.     

3种酵母发酵橄榄酒的发酵规律及香气分析

以橄榄为原料,分别利用三种酵母对橄榄酒进行发酵,研究橄榄酒整个发酵过程中酒精度、还原糖及酸度的变化规律;采取顶空固相微萃取和气相色谱质谱联用法对橄榄酒的香气成分进行分析比较。结果表明:三种酵母发酵过程中橄榄酒酒精度均逐渐上升,还原糖含量逐渐降低,酸度先上升后下降;果酒干酵母发酵周期最短,最终果酒酵母1383所酿橄榄酒酒精度最高,残留还原糖含量最低,酸度最低;同时果酒酵母1383、果酒干酵母和果酒酵母1596发酵的橄榄酒分别检出50、49、52种香气成分,其中相同的有35种,三种酒样的主要香气成分均为异戊醇。初步确定果酒酵母1383酿制的橄榄酒最优。      

Raspberry wine fermentation with suspended and immobilized yeast cells of two strains of Saccharomyces cerevisiae

The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 °C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602 g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212. Copyright © 2014 John Wiley & Sons, Ltd.     

Effects of sugar concentration on mango wine composition fermented by Saccharomyces cerevisiae MERIT.ferm

This study investigated the effect of initial sugar concentrations (^°Brix of 17, 23 and 30) on mango wine composition fermented by Saccharomyces cerevisiae MERIT.ferm. It was found that growth rate and maximum cell population were inversely correlated with initial sugar levels with the fastest growth rate and largest cell population in the low sugar fermentation. However, the cell population in the low and medium sugar fermentation declined significantly (from 8.7 and 8.2 log to 2 and 2.8 log, respectively) relative to the high sugar fermentation in which cell populations remained stable upon reaching the stationary phase (7.7 log). Glycerol production increased with increasing sugar content in low (13.4 g L^?1), medium (14.5 g L^?1) and high (15.9 g L^?1) sugar fermentation. In addition, high sugar fermentation had a negative impact on volatile production with significantly lower amounts of acetate esters (1.5 mg L^?1) but more acetic acid (0.54 g L^?1) compared to the low (5.0 mg L^?1 and 0.44 g L^?1, respectively) and medium (3.7 mg L^?1 and 0.49 g L^?1, respectively) sugar fermentations. Furthermore, volatiles especially terpene hydrocarbons (α‐caryophyllene was released) present in mango juice were significantly metabolised after fermentation, while numerous new volatile compounds (such as isobutyl alcohol, isoamyl alcohol, ethyl and acetate esters) were produced. Some terpene alcohols were released and converted into corresponding acetyl esters. This may indicate that the mango wines fermented with different levels of sugars would have different flavour aromas.