scholarly journals Nutrient Addition to Low pH Base Wines (L. cv. Riesling) during Yeast Acclimatization for Sparkling Wine: Its Influence on Yeast Cell Growth, Sugar Consumption and Nitrogen Usage

Beverages ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 10
Author(s):  
Belinda Kemp ◽  
Jessy Plante ◽  
Debra L. Inglis
Keyword(s):  
Alcoholic Fermentation ◽  
Low Ph ◽  
Nutrient Concentrations ◽  
Sparkling Wine ◽  
Sugar Consumption ◽  
Wine Production ◽  
Nutrient Sources ◽  
Time Required ◽  
The Impact ◽  
Kinetics Of

In traditional method sparkling wine production, to carry out a successful second alcoholic fermentation, yeast are acclimatized to stressful base wine conditions. Base wines typically have low pH, low nutrient concentrations, high acid concentrations, contain sulfur dioxide (SO2), and high ethanol concentrations. Supplementing yeast during the acclimatization stages prior to second alcoholic fermentation with different nutrient sources was assessed to determine the impact on yeast growth, sugar consumption and nitrogen usage. Four treatments were tested with Saccharomyces cerevisiae strain EC1118: the control (T1) with no additives; addition of diammonium phosphate (DAP) during acclimatization, (T2); Go-Ferm® inclusion during yeast rehydration (GF), (T3); and DAP + GF (T4). Results (n = 4) indicated that supplementing with DAP, GF or DAP + GF increased both the rate of sugar consumption and the concentration of viable cells during the yeast acclimatization phase in comparison to the control. Treatments supplemented with DAP + GF or DAP alone resulted in yeast consuming 228 and 220 mg N/L during the acclimatization phase, respectively. Yeast treated only with GF consumed 94 mg N/L in comparison to the control, which consumed 23 mg N/L. The time required to reach the target specific gravity (1.010) during acclimatization was significantly reduced to 57 h for yeast treated with DAP and GF, 69 h for yeast treated with DAP only and 81 h for yeast rehydrated with GF in comparison to 105 h for the control. Our results suggest that nutrients used during yeast acclimatization could have an important impact on the kinetics of second alcoholic fermentation.

scholarly journals The Impact of Non-Saccharomyces Yeast on Traditional Method Sparkling Wine

Fermentation ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 73 ◽  
Author(s):  
Nedret Ivit ◽  
Belinda Kemp
Keyword(s):  
Current Knowledge ◽  
Future Research ◽  
Sparkling Wine ◽  
Wine Production ◽  
Nutrient Supplementation ◽  
Saccharomyces Yeast ◽  
Sensory Profiles ◽  
The Impact ◽  
Saccharomyces Yeasts

The interest in non-Saccharomyces yeast for use in sparkling wine production has increased in recent years. Studies have reported differences in amino acids and ammonia, volatile aroma compounds (VOCs), glycerol, organic acids, proteins and polysaccharides. The aim of this review is to report on our current knowledge concerning the influence of non-Saccharomyces yeast on sparkling wine chemical composition and sensory profiles. Further information regarding the nutritional requirements of each of these yeasts and nutrient supplementation products specifically for non-Saccharomyces yeasts are likely to be produced in the future. Further studies that focus on the long-term aging ability of sparkling wines made from non-Saccharomyces yeast and mixed inoculations including their foam ability and persistence, organic acid levels and mouthfeel properties are recommended as future research topics.

Impact of varying degrees of powdery mildew infection (Uncinula necator (Schwein.) Burrill) on the volatile compounds of Chardonnay grapes, must and wine

OENO One ◽  
2012 ◽  
Vol 46 (4) ◽  
pp. 305
Author(s):  
Denis Rusjan ◽  
Tjaša Jug ◽  
Mojca Bavcon Kralj
Keyword(s):  
Powdery Mildew ◽  
Volatile Compounds ◽  
Alcoholic Fermentation ◽  
Ethyl Esters ◽  
Wine Production ◽  
Hydroxymethyl Furfural ◽  
Taste Evaluation ◽  
The Impact ◽  
First Time ◽  
Powdery Mildew Infection

<p style="text-align: justify;"><strong>Aims</strong>: The aims of this study are (i) to trace the major components responsible for the unpleasant mushroom, earthy and geranium odour in the transformation from grapes to wine in response to powdery mildew infection intensities, (ii) to determine the impact of an aggressive infection on volatile compounds in grapes and wine, and (iii) to determine their effect on the olfactory-taste evaluation of the resulting Chardonnay wine.</p><p style="text-align: justify;"><strong>Methods and results</strong>: A GC-MS technique was used to investigate the impacts of different degrees of oidium infections (0, 10, 50 and 100% of infected grapes) on the presence of volatiles in grapes, musts and wines. The number of volatiles was higher in oidium-infected grapes than in noninfected grapes, especially for terpenes, aldehydes and alcohols, with 1- octen-3-ol, 2-octen-1-ol, 2-heptanol and 2-octenal, the volatiles reminiscent of mushroom-, geranium-, and earthy-like odours, being detected in oidiuminfected grapes only. After overnight clarification, 1-octen-3-ol and 2- heptanol but also methyl-2-furoate were the only mushroom reminiscent volatiles detected in the musts. The infection also caused higher amounts of acetic acid, furfural and some of its derivates (2,5-furandicarboxaldehyde, 5-hydroxymethyl furfural, furaneol), most ethyl esters (except ethyl caprylate), 1-hexanol, maltol and 1-decanol in musts. After alcoholic fermentation the number of esters in young wines increased, whereas that of aldehydes decreased, especially in the wines produced from severely infected grapes. Though it was not detected by sensory analysis, we assume that the intensification of the odours reminiscent of pineapple, banana and coconut in the aged wines produced from infected grapes was likely a consequence of the increased amount of esters.</p><p style="text-align: justify;"><strong>Conclusion</strong>: Powdery mildew infection statistically decreased the freshness but enhanced the malty, sweet mouthfeel of Chardonnay wine, and neither the mushroom odour nor taste were perceived, which contradict some previously published findings.</p><p style="text-align: justify;"><strong>Significance and impact of the study</strong>: This study gives an answer to the significant problem of wine production from oidium-infected grapes. It reports for the first time the traceability of volatiles highly related to mushroom, earthy and geranium odours from the Chardonnay grapes to the wines. The overnight must clarification decreased the impacts of unpleasant volatiles on must and wine odour. This suggested that the oidium infection of the grapes does not necessarily hinder the production of wine, as no unpleasant odour could be sensory evaluated, not even in the wines made from highly infected grapes.</p>

scholarly journals Progress in Electrochemical (Bio)Sensors for Monitoring Wine Production

Chemosensors ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 66 ◽  
Author(s):  
Alina Vasilescu ◽  
Pablo Fanjul-Bolado ◽  
Ana-Maria Titoiu ◽  
Roxana Porumb ◽  
Petru Epure
Keyword(s):  
Phenolic Compounds ◽  
Method Development ◽  
Alcoholic Fermentation ◽  
Electrochemical Sensors ◽  
Industrial Process ◽  
Quality Parameters ◽  
Critical Parameters ◽  
Wine Quality ◽  
Wine Production ◽  
The Impact

Electrochemical sensors and biosensors have been proposed as fast and cost effective analytical tools, meeting the robustness and performance requirements for industrial process monitoring. In wine production, electrochemical biosensors have proven useful for monitoring critical parameters related to alcoholic fermentation (AF), malolactic fermentation (MLF), determining the impact of the various technological steps and treatments on wine quality, or assessing the differences due to wine age, grape variety, vineyard or geographical region. This review summarizes the current information on the voltamperometric biosensors developed for monitoring wine production with a focus on sensing concepts tested in industry-like settings and on the main quality parameters such as glucose, alcohol, malic and lactic acids, phenolic compounds and allergens. Recent progress featuring nanomaterial-enabled enhancement of sensor performance and applications based on screen-printed electrodes is emphasized. A case study presents the monitoring of alcoholic fermentation based on commercial biosensors adapted with minimal method development for the detection of glucose and phenolic compounds in wine and included in an automated monitoring system. The current challenges and perspectives for the wider application of electrochemical sensors in monitoring industrial processes such as wine production are discussed.

scholarly journals The effect of cation exchange resin treatment of grape must on the chemical and sensory characteristics of base wines for sparkling wine

2019 ◽  
Vol 34 (2) ◽  
pp. 91-101 ◽  
Author(s):  
Bruno Cisilotto ◽  
Simone Bertazzo Rossato ◽  
Evandro Ficagna ◽  
Luísa Carolina Wetzstein ◽  
Angelo Gava ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Volatile Compounds ◽  
Exchange Resin ◽  
Control Sample ◽  
Cation Exchange Resin ◽  
Sparkling Wine ◽  
Wine Production ◽  
Grape Must ◽  
Organoleptic Characteristics ◽  
The Impact

Ion exchange resins are polymers with high physical and chemical stability, which, upon activation, acquire positive charge (H+) ions which interchange with existing cations during musts or wines treatment. The chemical composition of the grape must, and wines are highly affected by said modifications. This study aimed to evaluate the impact of the cationic resin treatments on the physicochemical and organoleptic characteristics of base white wines for sparkling wine production. Thus for, Chardonnay must was exposed to a cation exchange resin specific for oenological usage, and fermented to obtain wines. Resulting wines included an untreated control sample with pH 3.15 and treated samples with pH 3.08, 3.02 and 2.97. Physicochemical and volatile compounds analyses as well as quantitative sensory evaluations were conducted. The results showed that, on the scenarios tested, treatments with cationic resins before fermentation resulted in wine with higher oxidative stability, with significative variation on the concentration of several volatile compounds that influenced organoleptic perceptions.

scholarly journals Use of Oak and Cherry Wood Chips during Alcoholic Fermentation and the Maturation Process of Rosé Wines: Impact on Phenolic Composition and Sensory Profile

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1236
Author(s):  
Inês Nunes ◽  
Ana C. Correia ◽  
António M. Jordão ◽  
Jorge M. Ricardo-da-Silva
Keyword(s):  
Alcoholic Fermentation ◽  
Wood Chips ◽  
Sensory Profile ◽  
Maturation Process ◽  
Phenolic Composition ◽  
Color Intensity ◽  
Wine Production ◽  
The Impact ◽  
The Rose ◽  
Rosé Wine

There is a lack of knowledge about the use of different wood species on rosé wine production. Thus, this work focused on the impact of the addition of wood chips from oak and cherry trees during the alcoholic fermentation and maturation process on rosé wine characteristics. Therefore, phenolic composition and sensory characteristics were monitored during the rosé wines’ production. The use of wood chips during alcoholic fermentation induced a significant increase of phenolic content in rosé musts. During rosé wine maturation, the wood chip contact induced significantly higher values of colored anthocyanins, color intensity, and polymeric pigments, and significantly lower values of color hue in the corresponding rosé wines. In terms of sensory profile, a tendency for lower scores of “overall appreciation” were attributed to control rosé wine, while significantly higher scores for “color intensity” descriptor were attributed to all rosé wines matured in contact with wood chips. For the majority of phenolic parameters and individual phenolic compounds quantified, a clear and specific influence of the use of oak and cherry wood chips was not detected, except for (+)-catechin, where the rosé wines produced in contact with cherry chips showed the highest values. This study provides relevant information for winemakers about the impact of the use of wood chips on rosé wine quality.

Prothrombin Evaluation as Obtained by Kinetics Studies of Antigen-Antibody Reaction in a Laser Nephelometer

1984 ◽  
Vol 52 (01) ◽  
pp. 015-018 ◽  
Author(s):  
A Girolami ◽  
A Sticchi ◽  
R Melizzi ◽  
L Saggin ◽  
G Ruzza
Keyword(s):  
Liver Cirrhosis ◽  
Cirrhotic Patient ◽  
Maximum Rate ◽  
Serum Proteins ◽  
Clotting Factors ◽  
Kinetics Studies ◽  
Maximum Value ◽  
Time Required ◽  
Antigen Antibody ◽  
Kinetics Of

SummaryLaser nephelometry is a technique which allows the evaluation of the concentration of several serum proteins and clotting factors. By means of this technique it is also possible to study the kinetics of the reaction between antigen and antibody. We studied the kinetics of the reaction between prothrombin and an antiprothrombin antiserum using several prothrombins namely: Prothrombin Padua, prothrombin Molise, which are two congenital dysprothrombinemias, cirrhotic, coumarin or normal prothrombins. Different behaviors in the kinetics of the reactions were shown even when the concentration of prothrombins was about the same in all plasma tested. These differences were analyzed by means of a computer (Apple II 48 RAM) programmed to solve four unknown equations (Rodbard’s equation). From the data so obtained one can see that when voltages at the beginning and at the end of the reaction are in all cases about the same, a clear difference in the time required to reach half the maximum value of the voltage can still be demonstrated. This parameter, which is expressed in minutes, is longer in coumarin and prothrombin Molise than in controls. On the contrary it is shorter in prothrombin Padua and has about the same value of controls in the cirrhotic patient. Moreover the time at which the maximum rate is obtained is longer in coumarin and prothrombin Molise than in controls and shorter in liver cirrhosis and prothrombin Padua. In conclusion data obtained show that coumarin prothrombin behaves in a different way from cirrhotic prothrombin and also that there is a different behaviour between the two congenital dysprothrombinemias.

scholarly journals Ice Coverage Induced by Depositing a Water Drop onto the Supercooled Substrate at Extreme Low Vapor Pressure

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 691
Author(s):  
Yugang Zhao ◽  
Zichao Zuo ◽  
Haibo Tang ◽  
Xin Zhang
Keyword(s):  
Vapor Pressure ◽  
Substrate Temperature ◽  
Water Drop ◽  
Industrial Processes ◽  
Aircraft Icing ◽  
Ice Coverage ◽  
Fundamental Understanding ◽  
Order Of Magnitude ◽  
The Impact ◽  
Kinetics Of

Icing/snowing/frosting is ubiquitous in nature and industrial processes, and the accretion of ice mostly leads to catastrophic consequences. The existing understanding of icing is still limited, particularly for aircraft icing, where direct observation of the freezing dynamics is inaccessible. In this work, we investigate experimentally the impact and freezing of a water drop onto the supercooled substrate at extremely low vapor pressure, to mimic an aircraft passing through clouds at a relatively high altitude, engendering icing upon collisions with pendant drops. Special attention is focused on the ice coverage induced by an impinging drop, from the perimeter pointing outward along the radial direction. We observed two freezing regimes: (I) spread-recoil-freeze at the substrate temperature of Ts = −15.4 ± 0.2 °C and (II) spread (incomplete)-freeze at the substrate temperature of Ts = −22.1 ± 0.2 °C. The ice coverage is approximately one order of magnitude larger than the frozen drop itself, and counterintuitively, larger supercooling yields smaller ice coverage in the range of interest. We attribute the variation of ice coverage to the kinetics of vapor diffusion in the two regimes. This fundamental understanding benefits the design of new anti-icing technologies for aircraft.

scholarly journals Morphology and crystallization kinetics of Rubber-modified Nylon 6 Prepared by Anionic In-situ Polymerization

2020 ◽  
Vol 27 (1) ◽  
pp. 204-215
Author(s):  
Hongkai Zhao ◽  
Dengchao Zhang ◽  
Yingshuang Li
Keyword(s):  
Crystallization Kinetics ◽  
In Situ Polymerization ◽  
Good Description ◽  
Nylon 6 ◽  
Avrami Equation ◽  
Infrared Analysis ◽  
Chain Segment ◽  
The Impact ◽  
Kinetics Of

AbstractIn this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.

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