Influence of yeast on the yield of fermentation and volatile profile of ‘Węgierka Zwykła’ plum distillates

The character of plum brandies depends on a unique aroma profile of the plum and the microbiota present on the surface of the fruits, as well as yeast used for fermentation. In this study, an evaluation of the effect of microorganisms applied for the fermentation of W?gierka Zwyk?a var. plum mashes and processing temperature (18 °C, 30 °C) on its efficiency and volatile profile, as well as taste and flavour of distillates obtained was performed. An estimation of the odour activity values (OAVs) of the volatile compounds was also conducted. Regardless of whether the fermentation was carried out using Saccharomyces bayanus wine yeast or by native microflora present on plums as well as raisins, the efficiency of this process was high and ranged between 91.7 and 96.7% of the theoretical efficiency. Especially rich in esters (among others ethyl acetate and isoamyl acetate) was the distillate derived after fermentation with the microflora of plums and raisins, at 18 °C. An evaluation of the individual aromatic effect of chemical compounds present in tested distillates, in terms of their OAVs, revealed that the highest OAVs were reached with isovaleraldehyde. Other compounds that showed aroma values >1 and possibly had an effect on the overall aroma of tested plum distillates were the following: hexanal, benzaldehyde, ethyl acetate, isoamyl acetate, ethyl benzoate, ethyl hexanoate, 1‐propanol, 2‐methyl‐1‐butanol, 3‐methyl‐1‐butanol and 1‐hexanol. The performed sensory ranking showed that the best rated distillate was the one obtained after fermentation with the indigenous microflora of plums and raisins, at 18 °C. Copyright © 2016 The Institute of Brewing & Distilling     

The impact of treatment of cereal mashes with hydrolases of non‐starch polysaccharides and pullulanase on the chemical composition of the obtained distillates

The distilling industry has been looking for more efficient technologies for spirit production. The pressureless starch liberation method (PLS) is an energy‐saving alternative to high‐pressure treatment of starch raw materials. Also, one of the promising solutions is the use of supportive enzymatic preparations during the mashing of starch raw materials. Rye and corn mashes obtained by the PLS method were treated with enzymes (pullulanase, xylanase, cellulases and cellobiase). The composition of volatile compounds in the distillates of the fermentation mashes was determined. Acetaldehyde was the dominant aliphatic carbonyl compound found in the raw distillates. Rye‐based fermentation distillates contained small amounts of propionaldehyde, isobutyraldehyde and isovaleraldehyde, which were not found in any of the corn distillates. The treatment of mashes with cellulolytic preparations caused an increase in the methanol content of the obtained distillates. All of the mashes treated with auxiliary enzymes yielded raw distillates with much higher levels of higher alcohols. The application of hydrolases of non‐starch polysaccharides, or pullulanase preparations, during the mashing of the starch raw materials affects the chemical composition of the distillates. Xylanase and pullulanase can be used in the processing of rye and corn mashes for subsequent use in distilled ethanol beverage production. Copyright © 2014 The Institute of Brewing & Distilling     

Factors affecting the methanol content and yield of plum brandy

This study was conducted to determine the influence of plum cultivar, harvest year, and plum component on the methanol content and the yield of plum brandy. Seven plum cultivars (Geneva Mirabelle, French Damson, Pozegaca, Oblinaya, Early Golden, Lohr, and Rosy Gage) grown in the Finger Lakes fruit region of New York State were processed into mash and juice. The samples of plum mash or juice were fermented with commercial Red Star wine yeast Montrachet (Sachharomyces cerevisiae Davis 522) for 12 d. The fermented samples were distilled, and the distillates were analyzed for methanol, ethanol, and higher alcohols by high-performance liquid chromatography. Duncan's multiple range tests show significant differences in the methanol content and the yield of plum brandy made from 7 plum cultivars. The harvest year also had a significant effect on the methanol content and the yield of plum brandy. Student's t-test results indicate that plum juices gave a lower methanol content of brandy than plum mashes without significantly reducing the brandy yield. The results of the current research can be used by the industry to select the better plum cultivar and to adopt the process to improve the product yield and quality. PRACTICAL APPLICATION: The brandy industry can apply the results of the current research to improve product yield and to reduce the methanol content of plum brandy. The economic benefits to the brandy producers adopting the brandy production process will be significant due to the sales of new products with an acceptable level of methanol.     

发酵型燕麦酸乳饮料的研制

以生牛乳、蔗糖、燕麦为主要原料,以羧甲基纤维素钠、高甲氧基果胶、结冷胶为稳定剂,制成发酵型燕麦酸乳饮料。通过不同稳定剂、蔗糖的配方组合,确定产品最佳配方。结果表明,羧甲基纤维素钠、高甲氧基果胶、结冷胶的最适添加量分别是0.3%、0.2%、0.04%,蔗糖的最适添加量为7%,按照该配方组合制备的发酵型燕麦酸乳饮料的口感和稳定性较好。     

Application of multiple sensory evaluations to produce fermented beverages made from sole whey using Kluyveromyces marxianus

Various fermented whey-based beverages have been developed to reduce waste. However, approaches to increase the preference of whey-based beverages are required because of the low sensory acceptability of whey. Here, we identified the better starting material (whey type), between raw whey (RW) and demineralised whey (DMW), and determined the optimal initial concentration using multiple sensory evaluations to develop acceptable fermented beverages made from sole whey with pure cultured Kluyveromyces marxianus (i.e. without additional ingredients and processing methods). Acceptance tests showed that fermented beverages made from DMW were superior to RW as the starting material. The amounts of ethanol produced were 5.0%, 7.6% and 9.5% v/v from the different initial DMW concentrations of 10%, 15% and 20% w/v, respectively. We observed a significant positive correlation (r_s = 0.32, P < 0.05) between the assessment attributes, strength of taste as alcohol beverage and overall acceptability, indicating that higher concentrations of DMW yielded a more desirable product.     

Evaluation of ethanol fermentation parameters for bioethanol production from sugar beet pulp and juice

The aim of this study was to investigate the efficient utilization of sugar beet pulp, as well as raw, concentrated raw and thick sugar beet juice, for bioethanol production. Different fermentation conditions were examined. The influence of raw material pre‐treatment (pasteurization or sterilization), type of batch culture process (stationary or shaken) as well as the type of Saccharomyces cerevisiae yeast preparation on the yields of the process were studied. Moreover, the fermentation process effectiveness was examined in connection with the quality of the obtained distillates. Sterilization, stationary batch culture and Safdistil C‐70 yeast preparation were identified as the most profitable factors for sugar beet pulp fermentation, providing a high fermentation efficiency and ethanol yield (87.7% of theoretical ethanol yield). Concentrated raw beet juice resulted in a value of 94.2% of theoretical yield, and thick juice a 92.6% yield. The results suggest that bioethanol production from sugar beet pulp and sugar beet juice has promise as an alternative fuel. The raw spirits obtained from the sugar beet juice were characterized as having the lowest quantity of volatile by‐products. Copyright © 2014 The Institute of Brewing & Distilling     

Preparation of an Alcoholic Beverage from Tea Leaves

The preparation of a fermented tea beverage from a Sri Lankan Broken Orange Pekoe (BOP) tea type is reported. The tea beverage was produced using 1–2.5% (w/v) Broken Orange Pekoe and was brewed using boiling sucrose sweetened (5–25°Brix) water (100°C for 3 min), followed by fermentation at 25°C, utilizing an 8.5% (v/v) inoculum of Saccharomyces cerevisiae G. A maximum ethanol of 14.91% (v/v) was obtained from an initial 25°Brix substrate with a 2.67°Brix drop per day. The tea beverage with an initial 15°Brix and 1.5% (w/v) tea yielded the best sensory score and was stable over a test period of 6 weeks at 15°C.     

Effects of cofermentation and sequential inoculation of Saccharomyces bayanus and Torulaspora delbruckii on durian wine composition

This work investigated the effects of cofermentation and sequential inoculation of Torulaspora delbrueckiiBiodiva and Saccharomyces bayanusEC‐1118 on chemical and volatile components of durian wines. Cofermentation and sequential inoculation resulted in higher production of ethanol (6.2% and 7.7% v/v, respectively) relative to the control (5.3% for S. bayanus and 5.8% for T. delbrueckii). Further, cofermentation and sequential inoculation produced higher amounts of acetyl esters and higher alcohols especially isoamyl alcohol and 2‐phenylethyl alcohol than monoculture fermentation. Most endogenous sulphur volatiles, especially disulphides that impart a character‐impact durian odour, declined to trace levels, but new ones such as thioesters were formed. Sulphur volatiles in the durian wines fermented by cofermentation and sequential inoculation accounted for 0.03% and 0.05% of total peak area. The study suggests that the use of S. bayanus in conjunction with non‐Saccharomyces such as T. delbrueckii may improve the aromatic intensity and complexity of durian wine.     

Characterisation of wines and distilled spirits from melon (Cucumis melo L.)

Melon fermentation and distillation was studied with a view to produce melon spirits. Three different substrates were obtained from melon (Cucumis melo L.). Sugar concentration was around 60–70 g L^?1 and the pH between 4.6 and 5.2. The substrates were clarified and then fermented at one of two pH levels at 20 °C. A commercial Saccharomyces cerevisiae starter culture was used to obtain melon wines with an alcohol concentration of 3.8–5.8% (v/v). The melon wines were distilled in a distillation column to yield distillates with an alcohol content of 33–60% (v/v). The major volatiles in the melon wines and in the distillates were analysed by gas chromatography (GC). The results demonstrated that melon could be a good substrate of fermentation and distillation but also yielded significant differences in the volatiles analysed in the different melon wines and distillates obtained from the different substrates in the different conditions of the experiment. Fermentation pH greatly affected the methanol, acetaldehyde, and butanol contents and thus the final quality of the spirits produced.     

The analysis of raw spirits – a review of methodology

Agricultural distillates (raw spirits) are alcoholic liquids obtained through distillation (preceded by alcoholic fermentation) of specific agricultural products that do not have the properties of ethyl alcohol or a spirit, but still retain the aroma and taste of the raw ingredients used. This review is a brief overview of agricultural distillates and of some methods commonly used (GC‐MS, GC‐FID, GC‐O, electronic nose) for performing quality assessments and for determining the composition and botanical origins of the raw spirits. Copyright © 2016 The Institute of Brewing & Distilling     

Chemical characteristics of Śliwowica Łącka and other plum brandies

BACKGROUND: ?liwowica ??cka is a strong, distilled, home‐made plum brandy produced in a submontane region of Poland. The aim of the present study was to determine the chemical composition of this alcoholic beverage (samples from the years 2001–2004) and compare it with that of other plum brandies. Gas chromatography and spectrophotometry methods were used to detect major volatile components. RESULTS: Home‐made Polish plum brandies generally contained more ethanol (64.7–72.5% v/v), methanol (5.59–8.74 g L^?1100°) and butanol (32–335 mg L^?1100°) and less isobutanol (406–491 mg L^?1100°), pentanol (4.3–14.9 mg L^?1100°) and 2‐phenylethanol (61–68 mg L^?1100°) than other samples. The amyl alcohols/1‐propanol and isobutanol/1‐propanol ratios might be used as indices to distinguish spontaneously fermented plum brandies from those produced by monoculture. Statistically significant differences (P < 0.01) were found in the plum brandy sensory characteristics examined. Total sensory scores of Polish plum brandies ranged between 12.0 and 14.3, while Slovakian Slivovica received the highest score (16.7). CONCLUSION: The results showed that plum brandies produced in the ??cko area are characterised by a similar and original chemical composition that results mainly from spontaneous fermentation as well as traditional production technology. Copyright © 2007 Society of Chemical Industry     

Alcoholic beverage from the egg yolk aqueous fraction

The development of new techniques for egg yolk fractionation gives new ovoproducts and also new by‐products and wastes. In particular, when the lipidic fraction from egg yolk plasma is obtained, an aqueous fraction, which still contains proteins, lipids and fermentable sugars, is generated. In this work, it is proposed to use this by‐product as substrate to produce a new alcoholic beverage. Fermentations employing Saccharomyces cerevisiae were carried out using this aqueous fraction, native or supplemented with glucose or molasses. The products obtained from supplemented media had ethanol concentrations similar to those found in commercial beverages (2.5–4.5% v/v). The highest ethanol production yield (91%) was obtained with the medium supplemented with molasses after three days of fermentation at 30°C. Results showed that a suitable fermented brew can be obtained to elaborate a beverage with adequate organoleptic characteristics. Copyright © 2016 The Institute of Brewing & Distilling     

Sensory Threshold Studies of Picrocrocin,the Major Bitter Compound of Saffron

This study is part of a wider project on the bitter taste of saffron and its preparations. A deeper knowledge on the taste perception of picrocrocin is necessary in order to develop products that satisfy consumer senses and provide them with adequate amounts of saffron major constituents, also appreciated for bioactivity. A systematic approach on the bitterness of picrocrocin, the major responsible compound, was conducted. A panel was trained specifically for the determination of taste detection and recognition thresholds of picrocrocin, which were found to be 5.34 and 7.26 mg/L, respectively, using the Ascending Forced Choice of Limits methodology. The threshold values were examined in water in absence and presence of other saffron constituents and ethanol and were found to decrease when served hot (61 ± 4 °C). Bitterness was enhanced in 40% (v/v) aqueous ethanol. In both aqueous and ethanol extracts, the presence of saffron volatiles improved bitterness perception. The usefulness of the study was tested in the case of commercial saffron based infusions.     

Proteolysis During the Fermentation of Ethanol-Supplemented Miso

ABSTRACT: Steam-cooked soybeans mixed with rice koji (2:1, w/w) were ground into a fine paste, combined with NaCl (0 to 12.5%) or sucrose (0 to 25%), and supplemented with 15% ethanol for fermentation. The proteolytic activities decreased with NaCl or sucrose; the dose-response effect of NaCl was much more effective than that of sucrose. When fermented with 15% ethanol and 12.5% sucrose at various moisture contents from 30.6 to 53.0%, proteolysis increased proportionally to the increase of moisture content. Mechanical agitation enhanced proteolysis. After 4 w of fermentation, free amino acid contents were higher in products fermented without pH control than in products fermented with pH control.     

Grappa quality from the Chianti and Montepulciano areas (Tuscany,Italy): monitoring the leaching of copper from distillation columns

The main aim of this work was to evaluate the leaching of copper in grappa from distillation plant that treats Cabernet and Sangiovese marcs (Montepulciano and Chianti, Tuscany). Copper content (determined by atomic absorption spectrometry, AAS) was 1.05 ± 0.03 mg L^?1 in industrial distillates (Cabernet marc, 82.3% alcohol, v/v), and 3.7 ± 0.2 μg L^?1 in artificial grappa (62.0%, Cabernet) obtained by distilling marc in a laboratory‐scale glassware plant. The artificial grappa distillate was refluxed over copper shavings, and copper content, C_Cu, was analysed in relation to reflux time and wear of the copper bell. The results showed that C_Cu trend was almost linear with increasing alcohol concentration and constant reflux time, and vice versa. The ratios of selected volatile components were not influenced by reflux on the shavings.     

玫瑰香槟啤酒的研制

采用瓶内二次发酵的方法,以玫瑰和麦芽为原料研制出一种具有特殊风格的玫瑰香槟啤酒。研究了玫瑰浸提的技术参数,探讨了玫瑰香槟啤酒的酿造工艺条件。结果表明:玫瑰花的最佳浸提条件为:料水比1∶60,浸提温度80℃,浸提时间1.5 h。玫瑰香槟啤酒的酿造条件为:玫瑰浸提液与啤酒原酒以40∶60的比例配比,接入2%的香槟酵母,加4%的糖,进行低温二次发酵,发酵6 d,得到的产品气泡含量丰富、残糖少、香气协调柔和,风味品质俱佳。     

Preparation of novel distinct highly aromatic liquors using fruit distillates

This work describes the preparation of aromatised liquors using deodorised and concentrated fruit distillates. The raw spirits were improved by making a partial deodorisation, using activated charcoal, followed by concentration, using a distiller. The liquors were prepared by a maceration process. The procedure is exemplified using fig distillates to prepare myrtle berry liquors. The acidity, copper, polyphenol and anthocyanin indexes and volatile and anthocyanin profiles were monitored in each preparation step. The concentration process increased the ethanol proof to 75% v/v and decreased the acidity and the copper content. The partial deodorisation decreased the levels of high molecular weight volatiles, while the content of lower molecular weight compounds that contribute to flavour was maintained. Delphinidin‐3‐O‐glucoside, cyanidin‐3‐O‐glucoside, petunidin‐3‐O‐glucoside and malvidin‐3‐O‐glucoside were the major anthocyanins.     

Influence of indigenous yeasts on the fermentation and volatile profile of plum brandies

The aim of this study was to determine the influence of different yeasts isolated from fresh blue plum fruits (Aureobasidium sp.) and spontaneously fermenting plum musts (Kloeckera apiculata and Saccharomyces cerevisiae), as well as commercial wine and distillery strains, on the fermentation and chemical composition of plum brandies. Gas chromatography methods were used to detect major volatile components. The most rapid fermentation occurred in musts inoculated with S. cerevisiae. However, the highest concentration of ethanol was detected in samples after spontaneous fermentation (8.40% v/v). Plum brandies obtained after distillation contained from 66.3 (K. apiculata) up to 74.3% v/v ethanol (spontaneous fermentation). The samples after spontaneous fermentation were distinguished by a high content of acetoin, ethyl acetate and total esters, accompanied by a low level of methanol and fusel alcohols. Non-Saccharomyces yeasts were responsible for higher concentrations of esters and methanol, while S. cerevisiae strains resulted in increased levels of higher alcohols. It was also found that isolated indigenous strains of S. cerevisiae synthesized relatively low amounts of higher alcohols compared to commercial cultures. Samples obtained using the distillery strain of S. cerevisiae received the highest score (18.2) during sensory analysis and were characterized by a well-harmonised taste and aroma.     

Application of Lactobacillus plantarum in Functional Products Based on Fermented Buckwheat

In this work, 12 plant‐based potential probiotic mashes were produced by fermenting buckwheat with lactic acid cocci of the Fresco DVS 1010 culture and the human‐derived isolate Lactobacillus plantarum HM1. The effect of single and coculture fermentation was studied at 30 and 37 ± 0.5 °C for 8 hr (5% CO₂), followed by a storage period of 21 days (6 ± 0.5 °C). Although milk is the typical growth medium for lactic acid bacteria (LAB), presumably viable counts of Fresco reached levels of 10⁸ to 10⁹ CFU/mL (specific growth rates ranging from 1.07 to 1.40 hr^?1) with higher counts in coculture fermentation (13%) that differed statistically significantly (P < 0.05). After storage, 194 to 4700 mg/kg lactic acid was found in the mashes, with significantly higher contents after cocultivation (11% to 96%). Based on the overall acceptance of the designed products, milk‐based mashes right after the fermentation were evaluated as the most satisfactory (3.3 to 3.6). Those after the storage period (21 days) exhibited an attractive sensory acceptability (2.2 to 3.2).     

饮用型苹果风味发酵乳的研制

以生牛乳和浓缩苹果汁为原料,以蔗糖为调味剂,添加一定量的水,经保加利亚乳杆菌和嗜热链球菌的混合乳酸菌发酵后均质,制得饮用型苹果酸奶。以发酵时间、发酵温度、苹果汁的添加量及菌种接种量为因素,以感官评价和理化检测为评价标准,通过单因素试验和正交试验,确定最佳发酵工艺条件:发酵温度42℃、苹果汁添加量4%、发酵菌种接种量0.2%、发酵时间9 h。以此发酵条件制成的饮用型酸奶色泽诱人,组织状态均匀稳定,风味醇厚,口感细腻爽滑,且理化指标均符合国家标准,为饮用型果汁酸奶的生产提供了一定的理论依据。