scholarly journals Results Concerning the Evolution of Bacterial Population during the Malolactic Fermentation

1970 ◽  
Vol 66 (2) ◽  
Author(s):  
Ionel POPESCU-MITROI ◽  
Marin GHEORGHIŢĂ ◽  
Felicia STOICA
Keyword(s):  
Bacterial Population ◽  
Alcoholic Fermentation ◽  
Malolactic Fermentation ◽  
Bacterial Density ◽  
Red Wines ◽  
Decline Phase ◽  
Population Evolution ◽  
Counting Methods ◽  
Direct Counting ◽  
Lactic Bacteria

During this experiment, the evolution of inner lactic bacteria microflora was monitored, during a spontaneous and conducted malolactic fermentation developed in the fall of the year 2006 at red wines obtained in Minis – Maderat wine yard. Thereby was monitored the bacterial population evolution, immediately after finishing the alcoholic fermentation (before developing the malolactic fermentation), through standard cultural method and through direct counting methods (counting with Thoma board and counting through Breed method). Results show that wines, at the end of alcoholic fermentation present bacterial loads between 102 and 104 cells/ml, after which in the exponential growing phase of the lactic bacteria registered at 5 days after sowing the selected malolactic bacteria, the bacterial density of wines to grow to 106 – 107 cells/ml, and at the end of malolactic fermentation, which matches the decline phase of lactic bacteria, the bacterial density of wines to get back to 105 cells/ml.

scholarly journals The Combined Use of Lachancea thermotolerans and Lactiplantibacillus plantarum (former Lactobacillus plantarum) in Wine Technology

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1356
Author(s):  
Ángel Urbina ◽  
Fernando Calderón ◽  
Santiago Benito
Keyword(s):  
Ethyl Acetate ◽  
Lactobacillus Plantarum ◽  
Alcoholic Fermentation ◽  
Red Wines ◽  
Combined Use ◽  
Saccharomyces Bayanus ◽  
Classical Methodology ◽  
Grape Juices ◽  
Lactic Bacteria ◽  
Lachancea Thermotolerans

Most commercialized red wines are produced through alcoholic fermentation performed by yeasts of the Saccharomyces genus, and a second fermentation performed by lactic bacteria of the Oenococus oeni species once the first is completely finished. However, the classical process can suffer complications, of which the risks can increase in grape juices with high contents of sugar and pH. Due to climate change, these situations are becoming more common in the winemaking industry. The main risks in those scenarios are alcoholic-fermentation stops or sluggish and undesirable bacteria development while alcoholic fermentation is not finished yet and wine still contains residual sugars. The study propose a novel alternative that offers a solution or reduces the risk of those scenarios while increasing acidity, which is another serious problem of warm viticulture regions. The alternative consists of the combined use of Lachancea thermotolerans to reduce the pH of musts that suffer from a lack of acidity, Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) to achieve malic acid stability during the first stages of alcoholic fermentation, and Saccharomyces bayanus to complete the alcoholic fermentation in difficult wines of high potential alcohol degree of over 15% (v/v). The new proposed biotechnology produced wines with higher final concentrations in lactic acid, glycerol, color intensity, ethyl lactate and 2-phenyl ethyl acetate in 2.39 g/L, 0.52 g/L, 21%, 48% and 37% respectively than the classical methodology where Saccharomyces genus performs alcoholic fermentation and later Oenococus oeni performs malolactic fermentation. Additionally, the new alternative produced wines with lower concentration in ethanol, pH, acetic acid, ethyl acetate, diacetyl and 1-propanol in 0.37% (v/v), 0.26, 0.08 g/L, 22%, 69% and 28% respectively than the classic method.

scholarly journals THE ANALYSIS OF BURGUND RED WINES POLYPHENOLS CONTENT OBTAINED IN MINIS AND MURFATLAR VINEYARDS

1970 ◽  
Vol 62 ◽  
Author(s):  
Claudia Muresan
Keyword(s):  
Quality Improvement ◽  
Phenolic Compounds ◽  
Fermentation Process ◽  
Alcoholic Fermentation ◽  
Malolactic Fermentation ◽  
Chemical Analyses ◽  
Red Wines ◽  
Wine Making ◽  
The One ◽  
Physical And Chemical

The researchers that were done regarded the evolution of phenolic compounds at superiors red wines from Burgund variety, obtained in Minis and Murfatlar vineyards during five years period of time. In the purpose to obtain extractive wines and intensely coloured, external enzymatic mixtures was experienced during the maceration and fermentative processes, and for some technological phases improvement for primary wine making process. During the hole period of study physical and chemical analyses were done to superior red wines obtained from Burgund variety, beginning with the end of alcoholic fermentation, malolactic fermentation, at 3 months, 6 months, 9 months, 12 months, 18 months and after that yearly, as for the wines obtained with external enzymatic mixtures used during the maceration – fermentation process, as for the one which weren’t treated with enzymes. Through external enzymatic mixtures utilisation the antocians and total poliphenols to superior red wines obtained is the biggest contribution which contribute the their quality improvement, especially to colours and extractive character.

scholarly journals Observations related to the causes and consequences of stuck fermentation in vinification

OENO One ◽  
1999 ◽  
Vol 33 (1) ◽  
pp. 39
Author(s):  
Pascal Ribéreau-Gayon
Keyword(s):  
Human Error ◽  
Alcoholic Fermentation ◽  
Red Wine ◽  
Nutritional Deficiencies ◽  
Red Wines ◽  
Yeast Growth ◽  
Temperature Variations ◽  
Volatile Acidity ◽  
Lactic Bacteria ◽  
Thermal Shocks

<p style="text-align: justify;">The serious dangers arising if premature arrest of alcoholic fermentation (stuck fermentation) occurs are well known. If sugar is present, bacteria development may increase volatile acidity.</p><p style="text-align: justify;">There are several reasons explaining why such phenomena are more common today : 1) higher levels of alcohol ; 2) the more widespread use of closed vats for red wine where there is no contact with the air ; 3) intensive clarification of white musts ; 4) better management of problems related to difficult ends of fermentation.</p><p style="text-align: justify;">Apart from insufficient yeasting and nutritional deficiencies (nitrogen), the causes of premature arrest are as follows. In red wines : 1) inadequate sulphiting of the harvest leading to early development of lactic bacteria ; 2) poorly controlled or excessive temperature, especially during yeast growth ; 3) insufficient aeration of yeasts during their growth. In white wines : 1) must extraction which is too rapid or excessive clarification ; 2) inadequate aeration ; 3) excessive temperature variations (thermal shocks).</p><p style="text-align: justify;">If difficulties occur despite adequate precautions, the reasons for this may be found in the specific constitution of the must. However, a more likely cause may be human error.</p>

scholarly journals Use of Yeast Mannoproteins by Oenococcus oeni during Malolactic Fermentation under Different Oenological Conditions

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1540
Author(s):  
Aitor Balmaseda ◽  
Laura Aniballi ◽  
Nicolas Rozès ◽  
Albert Bordons ◽  
Cristina Reguant
Keyword(s):  
Energy Source ◽  
Nutrient Medium ◽  
Alcoholic Fermentation ◽  
Hydrolytic Activity ◽  
Malolactic Fermentation ◽  
Oenococcus Oeni ◽  
Consumption Patterns ◽  
Inhibitor Compounds

Oenococcus oeni is the main agent of malolactic fermentation in wine. This fermentation takes place after alcoholic fermentation, in a low nutrient medium where ethanol and other inhibitor compounds are present. In addition, some yeast-derived compounds such as mannoproteins can be stimulatory for O. oeni. The mannoprotein concentration in wine depends on the fermenting yeasts, and non-Saccharomyces in particular can increase it. As a result of the hydrolytic activity of O. oeni, these macromolecules can be degraded, and the released mannose can be taken up and used as an energy source by the bacterium. Here we look at mannoprotein consumption and the expression of four O. oeni genes related to mannose uptake (manA, manB, ptsI, and ptsH) in a wine-like medium supplemented with mannoproteins and in natural wines fermented with different yeasts. We observe a general gene upregulation in response to wine-like conditions and different consumption patterns in the studied media. O. oeni was able to consume mannoproteins in all the wines. This consumption was notably higher in natural wines, especially in T. delbrueckii and S. cerevisiae 3D wines, which presented the highest mannoprotein levels. Regardless of the general upregulation, it seems that mannoprotein degradation is more closely related to the fermenting medium.

scholarly journals Torulaspora delbrueckii promotes malolactic fermentation in high polyphenolic red wines

LWT ◽  
2021 ◽  
pp. 111777
Author(s):  
Aitor Balmaseda ◽  
Nicolas Rozès ◽  
Albert Bordons ◽  
Cristina Reguant
Keyword(s):  
Malolactic Fermentation ◽  
Red Wines ◽  
Torulaspora Delbrueckii

Patagonian red wines: selection of Lactobacillus plantarum isolates as potential starter cultures for malolactic fermentation

2013 ◽  
Vol 29 (9) ◽  
pp. 1537-1549 ◽  
Author(s):  
Bárbara Mercedes Bravo-Ferrada ◽  
Axel Hollmann ◽  
Lucrecia Delfederico ◽  
Danay Valdés La Hens ◽  
Adriana Caballero ◽  
...  
Keyword(s):  
Lactobacillus Plantarum ◽  
Malolactic Fermentation ◽  
Starter Cultures ◽  
Red Wines ◽  
Selection Of

scholarly journals Efficacy of Clarithromycin Depends on the Bacterial Density in Clarithromycin-Heteroresistant Helicobacter pylori Infections: An In Situ Detected Susceptibility and Quantitative Morphometry-Based Retrospective Study

2021 ◽  
Vol 27 ◽  
Author(s):  
Jewel Ju Ea Kim ◽  
Ildikó Kocsmár ◽  
György Miklós Buzás ◽  
Ildikó Szirtes ◽  
Orsolya Rusz ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Retrospective Study ◽  
Bacterial Population ◽  
Tissue Sample ◽  
Bacterial Density ◽  
Resistant Bacteria ◽  
Hybridization Technique ◽  
Predictive Role

The global rise in clarithromycin (Cla) resistance is considered to be the main contributor of Helicobacter pylori (Hp) eradication failures. In nearly half of the Cla-resistant Hp infections, Cla-susceptible bacteria are simultaneously present with the Cla-resistant ones (Cla-heteroresistance). The proportion of resistant bacteria in the bacterial population (R-fraction) and its predictive role for the use of Cla-based therapies in Cla-heteroresistant infections has not yet been investigated. Our retrospective study analyzed gastric biopsy samples of 62 Hp-positive patients with Cla-heteroresistant infection. Fluorescence In Situ Hybridization technique was used to visualize the coexistence of resistant and susceptible bacteria within one tissue sample. R-fraction was quantified on multichannel microimages by digital morphometry. Resistant bacteria had a patchy distribution within the whole bacterial population causing high diversity among the investigated areas. Patients were subdivided into two major groups according to whether a Cla-based eradication attempt was conducted before or after the biopsy sampling. R-fraction was significantly lower among cases having only one previous Cla-based eradication attempt vs. those that had multiple previous eradications, including at least one Cla-containing therapy (0.41 vs. 0.89, p = 0.0308). Majority of the patients without previous eradication attempt had successful eradication with Cla-containing regimen (59.26%), verified by a negative 13C-urea breath test or control biopsy. Multivariable model indicated that the therapeutic outcome using Cla-based regimens depended on the bacterial density rather than the R-fraction. Our study raises the potential use of Cla-containing eradication therapies in certain Cla-heteroresistant Hp infections, taking into account the possible predictive role of bacterial density.

scholarly journals Development of organic acids and volatile compounds in cider during malolactic fermentation

2014 ◽  
Vol 32 (No. 1) ◽  
pp. 69-76 ◽  
Author(s):  
H. Zhao ◽  
F. Zhou ◽  
P. Dziugan ◽  
Y. Yao ◽  
J. Zhang ◽  
...  
Keyword(s):  
Organic Acids ◽  
Volatile Compounds ◽  
Carbonyl Compounds ◽  
Alcoholic Fermentation ◽  
Total Concentration ◽  
Malolactic Fermentation ◽  
High Concentration ◽  
Volatile Acidity ◽  
Organoleptic Characteristics

The effect of malolactic fermentation (MLF) on the flavour quality of cider was examined. Leuconostoc mesenteroides subsp. mesenteroides Z25 was used to start MLF taking place at 25&deg;C for 12 days after the completion of alcoholic fermentation (AF) by Saccharomyces cerevisiae. Strain Z25 showed good activity in starting MLF of cider with 10% alcoholic concentration. The content of malic acid, whose high concentration gives negative organoleptic characteristics to the cider, dropped significantly from 4.0 g/l to 0.25 g/l via MLF. The concentration of lactic acid increased significantly from 0.99 g/l to 3.50 g/l, contributing to volatile acidity. The acetic acid content of the ciders was 0.74 g/l. Among 51 volatile compounds detected by GC-MS, higher alcohols, esters, and carbonyl compounds were formed in ciders through MLF. The total concentration of aromatic substances doubled compared to the controls. The occurrence of MLF started by strain Z25 enabled the cider containing more volatile compounds and an acceptable adjustment of organic acids. This is the first report on using L. mesenteroides subsp. mesenteroides strain Z25 to start the MLF of apple wine improving the flavour quality of the cider produced. &nbsp;

Formation of Biogenic Amines throughout the Industrial Manufacture of Red Wine

2006 ◽  
Vol 69 (2) ◽  
pp. 397-404 ◽  
Author(s):  
Á. MARCOBAL ◽  
P. J. MARTÍN-ÁLVAREZ ◽  
M. C. POLO ◽  
R. MUÑOZ ◽  
M. V. MORENO-ARRIBAS
Keyword(s):  
Amino Acids ◽  
Sulfur Dioxide ◽  
Biogenic Amines ◽  
Biogenic Amine ◽  
Alcoholic Fermentation ◽  
Red Wine ◽  
Malolactic Fermentation ◽  
Industrial Manufacture ◽  
Amino Acid Precursors ◽  
Wine Aging

Changes in biogenic amines (histamine, methylamine, ethylamine, tyramine, phenylethylamine, putrescine, and cadaver-ine) were monitored during the industrial manufacture of 55 batches of red wine. The origin of these amines in relation to must, alcoholic fermentation, malolactic fermentation, sulfur dioxide addition, and wine aging and the interactions between amines and their corresponding amino acids and pH were statistically evaluated in samples from the same batches throughout the elaboration process. Some amines can be produced in the grape or the musts (e.g., putrescine, cadaverine, and phenylethylamine) or can be formed by yeast during alcoholic fermentation (e.g., ethylamine and phenylethylamine), although quantitatively only very low concentrations are reached in these stages (less than 3 mg/liter). Malolactic fermentation was the main mechanism of biogenic amine formation, especially of histamine, tyramine, and putrescine. During this stage, the increase in these amines was accompanied by a significant decline in their amino acid precursors. Significant correlations between biogenic amine formation and the disappearance of their corresponding amino acids were observed, which clearly supports the hypothesis that malolactic bacteria are responsible for accumulation of these amines in wines. No increase in the concentration of biogenic amines was observed after SO2 addition and during wine aging, indicating that sulfur dioxide prevents amine formation in subsequent stages.

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