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This study aims to assess the effect of water variation on bioethanol production from cassava peels (CP) using Saccharomyces cerevisiae yeast as the ethanologenic agent.

The milled CP was divided into three treatment groups in a small-scale flask experiment where each 20 g CP was subjected to two-stage hydrolysis. Different amount of water was added to the fermentation process of CP. The fermented samples were collected every 24 h for various analyses.

The results of the fermentation revealed that the highest ethanol productivity and fermentation efficiency was obtained at 17.38 ± 0.30% and 0.139 ± 0.003 gL⁻¹ h⁻¹. The study affirmed that ethanol production was increased for the addition of water up to 35% for the CP hydrolysate process.

The finding of this study demonstrates that S. cerevisiae is the key player in industrial ethanol production among a variety of yeasts that produce ethanol through sugar fermentation. In order to design truly sustainable processes, it should be expanded to include a thorough analysis and the gradual scaling-up of this process to an industrial level.

This paper is an original research work dealing with bioethanol production from CP using S. cerevisiae microbe.

1. Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

2. Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

3. Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

4. Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

The purpose of this paper is to identify and analyse the fermentative properties of a strain of indigenous Wickerhamomyces anomalus (W. anomalus) from Rosa roxburghii Tratt (R. roxburghii).

Morphological and molecular methods were used to determine the species of the selected strain W. anomalus C11. The physiological tolerances to glucose, ethanol, citric acid and sulphur dioxide (SO₂) were further assessed by checking the growth of cells, and the oenological performances were proved to measure the related fermentative properties of R. roxburghii wines.

The W. anomalus C11 strain could be grown faster than commercial S. cerevisiae X16 in its logarithmic growth period and had preferable tolerances to glucose, ethanol, citric acid and SO₂. Moreover, this strain of native R. roxburghii yeast W. anomalus C11 produced less sulphuretted hydrogen and had a higher β-glucosidase activity. Furthermore, W. anomalus C11 could reduce the volatile acids, reduce the sourness and enhance volatile aroma richness and complexity of R. roxburghii wines including types of aroma and content thereof. Taken together, the R. roxburghii native yeast W. anomalus C11 may have potential for use in R. roxburghii winemaking.

(1) The fermentative properties of a strain of indigenous W. anomalus (named as C11) from R. roxburghii was evaluated. (2) The strain of W. anomalus C11 had preferable tolerances to glucose, ethanol, citric acid and SO₂. (3) This strain of native R. roxburghii yeast W. anomalus C11 produced less sulphuretted hydrogen and had a higher ß-glucosidase activity. (4) W. anomalus C11 could reduce the volatile acids, reduce the sourness and enhance volatile aroma richness and complexity of R. roxburghii wines including types of aroma and content thereof.

Describes the use of the decomposition method for solving the differential system governing the interaction between two species, based on the Lotka‐Volterra model. The Alienor method is applied for identifying the parameters of the model, which are the intrinsic rates of natural increase of the different species and their interaction coefficients.

Spoilage due to yeast and mould growth is a major issue for yoghurt quality and shelf‐life. There is a need to develop natural alternatives to chemical preservation. The purpose of this paper is to determine the effectiveness of mycocinogenic yeast Williopsis saturnus var. saturnus as a biocontrol agent against spoilage yeasts and moulds in plain yoghurt.

Yoghurts were prepared from reconstituted skim milk and were challenged with spoilage yeasts and moulds. The treatment contained the added mycocinogenic yeast and the control without. All yoghurts were incubated at 30^○C. Yeast and mould growth were determined by observing gas formation and mould colony occurrence at regular intervals.

W. saturnus var. saturnus inhibited growth of lactose‐fermenting and galactose‐fermenting yeasts (Candida kefir and Kluvyveromyces marxianus), and lactose non‐fermenting but galactose fermenting yeasts (strains of Saccharomyces cerevisiae and Saccharomyces bayanus). The yeast also inhibited growth of dairy moulds including Byssochlamys, Eurotium and Penicillium.

The inhibition of this mycocinogenic yeast against yeasts and moulds was dependent upon the concentration of the latter. Thus, hygiene and good manufacturing practice are essential in order to keep the contaminant load down and to ensure the effectiveness of the mycocinogenic yeast.

The use of mycocinogenic yeast to control spoilage yeasts and moulds in yoghurt is a novel approach with a potential to minimise yoghurt spoilage and extend the shelf‐life of yoghurt.

The purpose of this paper is to analyse data from routine quality control samples of beer over a ten year period to provide comparisons with a previous study in 2006 and apply interpretations to the contemporary beer market.

Data from laboratory analysis of 1,469 beers submitted for due diligence quality assurance from commercial microbreweries were analysed. Additional commercial samples were taken for analysis of sour beers and cask conditioned beers as examples of niche product areas.

Style characteristics were summarized as a reference for industry evaluation and as a basis for comparisons. Differences were noted between the characteristics found and those of a similar study in 2006. Average alcohol by volume increased by 1.2 per cent, bitterness levels increased by 6.1 per cent while colour decreased by 22 per cent. These differences suggest that standard UK beers are undergoing change. A study of sour beers indicated specific features in this recently popular style and confirmed the use of a different microbiology. Analysis of cask ales indicated some variability in quality suggesting the need for greater quality control.

The comparison with the previous study has limitations as the samples were not individually comparable but were from major established microbreweries and so representative of the industry. The work analysed UK beers only but will act as a base line for comparison to other markets. Moreover, the data may be relevant to other forms of market analysis seeking to identify factors associated to consumer preferences.

The data presented have relevance to breweries looking to develop their portfolios and product descriptions, to the drinking public and to regulatory bodies in providing a benchmark for comparisons and for assisting in defining the recently promoted term “craft beer”.

The findings are relevant to beverage development and consumer education of alcoholic beverages by allowing discrimination between styles with different characteristics affecting consumer choice and when assessing styles for industrial, legislative and health research. Beers today appear to be more varied than in past decades but show lower colour and higher bitterness characteristics. As these features particularly relate to ingredients they may have implications in their contributions to diet and health.

The work has value in replicating the previous study to illustrate changes and trends. It presents novel data on recently popular sour beers and assesses traditional cask beer with implications for product quality.

Mixed fermentation with Saccharomyces cerevisiae and non-Saccharomyces yeasts has become an oenlogical tool to improve wines’ organoleptic properties. However, the maximum utilization of this method is dependent upon understanding the influence of mixed cultures on the physiology of S.cerevisiae and non-Saccharomyces yeasts.

In this study, the supernatants from 48 h mixed-culture fermentation were added to the pure cultures of Issatchenkia orientalis and Saccharomyces, respectively. And the authors used RNA sequencing to determine the transcriptome change of I.orientalis and S.cerevisiae in a mixed culture.

The results showed that multiple genes associated with cell growth and death were differentially expressed. Genes related to biosynthesis of amino acids were enriched among those upregulated in the mixed-fermentation supernatant. Meanwhile, the differential expression level of genes encoding enzymes essential for formation of aroma compounds was found in the single and in the mixed fermentation. The high expression level of molecular chaperones Hsp70, Hsp90 and Hsp110 suggests that metabolites of mixed-culture fermentation may lead to aggregation of misfolded proteins. Moreover, upregulation of ethanol dehydrogenase I ADH1 in the mixed-culture fermentations was highlighted.

This is the first time that RNA-seq was used to analyze changes in the transcriptome of mixed cultures. According to the results the authors’ manuscript provided, an integrated view into the adaptive responses of S.cerevisiae and non-Saccharomyces yeasts to the mixed-culture fermentation is benefit for the potential application of S.cerevisiae and non-Saccharomyces yeasts in fruit wine brewing.

The aim of this study is to find out the appropriate fermentation conditions of Jerusalem artichoke powder (JAP) based media to obtain light beverage containing inulin.

JAP water suspension or filtrate were used for preparation of growth media with or without enzymatic hydrolysis of inulin for fermentation by Zymomonas mobilis 113 “S” or Saccharomyces cerevisiae.

If enzymatic hydrolysis of inulin was not used significantly higher amount of inulin (7.42 per cent) was unconverted by Z. mobilis than by S. cerevisiae (2.22 per cent) while the ethanol concentration was much higher (2.86 per cent) after S. cerevisiae fermentation than after Z. mobilis fermentation (1.21 per cent). Considerably more ethanol was produced by Z. mobilis during co‐fermentation with Fructozyme L of JAP suspension filtrate (5.98 per cent) and suspension (4.96 per cent). Analyses of volatile components of fermentation broths showed that for production of inulin containing light beverages the best was Z. mobilis fermentation of JAP water suspension or filtrate without enzymatic treatment. FT–IR spectroscopy can be used as a quick semi‐quantitative method for evaluation of inulin content.

JAP – containing not only inulin but all tuber ingredients, was used as a media for ethanol fermentations by Z. mobilis 113 “S” or S. cerevisiae with or without hydrolysis of inulin. It was shown that Z. mobilis fermentation broths containing 7.42 per cent of inulin can be used as beverage with prebiotic‐dietary fibre benefits. The taste of this product can be regulated by appropriate fermentation conditions and the concentration of fructose and ethanol.

The purpose of this paper is to evaluate the protective effects of Persian gum and gum Arabic on the survival of Lactobacillus plantarum subsp. plantarum PTCC 1896, Escherichia coli, Xanthomonas axonopodis, and Saccharomyces cerevisiae during freeze drying.

Cultures were harvested from the early stationary phase and enumerated after dilution according to the Milse Misra method. Bacterial suspensions were mixed with protective agents and frozen at –80°C before drying in a freeze dryer. Survival rates were determined both immediately during freeze drying and after 14 days of cold storage (at 4°C).

Compared to gum Arabic 5 and 10 percent (W/V) or skim milk 10 percent (W/V), Persian gum 1 percent (W/V) showed no significantly different effects on the survival of Lactobacillus plantarum subsp. plantarum PTCC 1896 (p<0.05). Similarly, no significant differences (p<0.05) were observed between Persian gum 6 percent (W/V), gum Arabic 6 percent (W/V), the combination of Persian gum 3 percent (W/V) and gum Arabic 3 percent (W/V), and skim milk 10 percent (W/V) in terms of their effects on the survival of Escherichia coli. Skim milk 10 percent (W/V) was, however, found to have significant (p<0.05) effects on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. Statistically significant (p<0.05) effects were observed after 14 days of cold storage (4°C) by Persian gum 6 percent (W/V) on the survival of Escherichia coli and by gum Arabic 6 percent (W/V) on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. It was concluded that protective agents could be replaced by Persian gum for its effect on the survival rate of Escherichia coli and by skim milk for its effects on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. Persian gum 6 percent (W/V) seemed to be the best protective agent for Escherichia coli during 14 days of its storage as gum Arabic 6 percent (W/V) seemed to have the same performance for Xanthomonas axonopodis and Saccharomyces cerevisiae. Persian gum 1 percent (W/V) was also found an alternative protective agent for the freeze drying of Lactobacillus plantarum subsp. plantarum PTCC 1896.

As Iranian Persian gum is cheap due to its wide availability and seems to have effects similar to those of gum Arabic and skim milk at low concentrations, it may be considered a good candidate for industrial applications.

Bales of cotton run through the gins and textile mill instruments, stick to them and make it cumbersome for the ginning mill workers. This is so because more time and money have to be invested in cleaning these instruments. The stickiness of cotton causes health hazards to the workers, decreases the yarn quality and economic loss to the textile industry. The effect of cotton stickiness on textile ginning, various methods for cotton stickiness detection and the steps for reduction are discussed.

The different methods that are available for detecting and measuring cotton stickiness are described. The sugars that cause stickiness are either of plant origin (physiological sugars) or from the feeding insects (entomological origin). The methods for stickiness detection and reduction are discussed under physical, chemical and biological categories.

This review suggests possible ways to mitigate cotton stickiness.

One of the major issues of the textile industry is honeydew-contaminated cotton stickiness. However, there are few papers on detection methods for analyzing honeydew cotton stickiness along with the approaches to reduce stickiness. This paper summarizes different methods along with a study for detection as well as reduction of cotton stickiness.

The purpose of this paper is to assess the potential of papaya juice fermentation and to evaluate the kinetic changes of volatile organic compounds (VOCs) produced during fermentation by three commercial wine yeasts.

Laboratory‐scale fermentations were carried out in papaya juice using three commercial wine yeasts Saccharomyces cerevisiae var. bayanus strains EC‐1118 and R2, and S. cerevisiae MERIT.ferm. Brix, pH, optical density and yeast cell count were determined during fermentation. VOCs were analysed by headspace‐solid phase microextraction with gas chromatography‐mass spectrometry‐flame ionization detector (HS‐SPME‐GC‐MS/FID).

During fermentation, the three wine yeasts grew actively and showed similar growth patterns. Changes in Brix and pH were similar among the three yeasts. A range of VOCs were produced during fermentation including fatty acids, alcohols, acetaldehyde, esters and acetoin. Esters were the most abundant VOCs produced. Some VOCs indigenous to the papaya juice such as benzaldehyde, β‐damascenone and benzyl isothiocyanate were consumed during fermentation. Some VOCs increased initially, and then decreased during fermentation. Overall, the profiles of VOC changes during fermentation were similar among the three yeasts with some differences observed.

The paper suggests that papaya fermentation with S. cerevisiae yeasts are likely to result in papaya wine with similar flavours. New approaches are required to produce papaya wine with distinct flavours and to enable differentiation of papaya wines by exploiting non‐Saccharomyces yeasts in conjunction with Saccharomyces yeasts and/or by adding selected nitrogen sources.