scholarly journals Use of Lachancea thermotolerans for Biological vs. Chemical Acidification at Pilot-Scale in White Wines from Warm Areas

Fermentation ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 193
Author(s):  
Cristian Vaquero ◽  
Pedro Miguel Izquierdo-Cañas ◽  
Adela Mena-Morales ◽  
L. Marchante-Cuevas ◽  
José María Heras ◽  
...  
Keyword(s):  
Tartaric Acid ◽  
Carbonyl Compounds ◽  
Pilot Scale ◽  
Harvest Time ◽  
Common Procedure ◽  
The Third ◽  
Volatile Metabolites ◽  
Sequential Inoculation ◽  
Normal Feature ◽  
Lachancea Thermotolerans

Climate change is affecting vineyards, resulting in grapes with a low acidity a high pH and sugar at harvest time. The most common procedure so far to improve the acidity and reduce the final pH of wines is to use tartaric acid, but wine can also be acidified microbiologically using Lachancea thermotolerans yeasts, a natural bio-tool that acidifies gradually during the first stage/days of fermentation. Two strains of L. thermotolerans were compared with one Saccharomyces cerevisiae at a pilot-scale under similar fermentation conditions and in duplicate. A sequential inoculation was performed on the third day for the non-Saccharomyces, producing only about 1 g/L of lactic acid, which was suitable for comparison with the Saccharomyces, to which 1.5 g/L of tartaric acid had been added to lower the final pH. The three fermentations ended with a total acidity without significant differences. A significant and normal feature of the L. thermotolerans yeasts is their higher propane-1,2,3-triol production, which was observed in the Laktia yeast, and the acetic acid was <0.3 g/L. The amount of volatile metabolites was generally higher for non-Saccharomyces and the increase was seen in carbonyl compounds, organic acids, lactones, fumaric compounds, and phenols. Finally, the sensory analysis showed that there were hardly any significant differences, even though the non-Saccharomyces had a higher quantity of volatile metabolites, which could lead to a good acceptance of the product, since biological acidification was used, generating a more natural product.

scholarly journals Molecular Characterization and Enological Potential of A High Lactic Acid-Producing Lachancea thermotolerans Vineyard Strain

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 595 ◽  
Author(s):  
Georgios Sgouros ◽  
Athanasios Mallouchos ◽  
Maria-Evangelia Filippousi ◽  
Georgios Banilas ◽  
Aspasia Nisiotou
Keyword(s):  
Climate Change ◽  
Lactic Acid ◽  
Molecular Mechanisms ◽  
Lactic Acid Production ◽  
Adh Genes ◽  
Key Enzyme ◽  
Sequential Inoculation ◽  
High Production ◽  
Grape Wine ◽  
Lachancea Thermotolerans

Lactic acid production is an important feature of the yeast Lachancea thermotolerans that has gained increasing interest in winemaking. In particular, in light of climate change, the biological acidification and ethanol reduction by the use of selected yeast strains may counteract the effect of global warming in wines. Here, the enological potential of a high lactate-producing L. thermotolerans strain (P-HO1) in mixed fermentations with S. cerevisiae was examined. Among the different inoculation schemes evaluated, the most successful implantation of L. thermotolerans was accomplished by sequential inoculation of S. cerevisiae, i.e., at 1% vol. ethanol. P-HO1produced the highest levels of lactic acid ever recorded in mixed fermentations (10.4 g/L), increasing thereby the acidity and reducing ethanol by 1.6% vol. L. thermotolerans was also associated with increases in ethyl isobutyrate (strawberry aroma), free SO2, organoleptically perceived citric nuances and aftertaste. To start uncovering the molecular mechanisms of lactate biosynthesis in L. thermotolerans, the relative expressions of the three lactate dehydrogenase (LDH) paralogous genes, which encode the key enzyme for lactate biosynthesis, along with the alcohol dehydrogenase paralogs (ADHs) were determined. Present results point to the possible implication of LDH2, but not of other LDH or ADH genes, in the high production of lactic acid in certain strains at the expense of ethanol. Taken together, the important enological features of P-HO1 highlighted here, and potentially of other L. thermotolerans strains, indicate its great importance in modern winemaking, particularly in the light of the upcoming climate change and its consequences in the grape/wine system.

scholarly journals Postharvest Losses from Delayed Harvest and during Common Storage of Short-day Onions

HortScience ◽  
1994 ◽  
Vol 29 (7) ◽  
pp. 802-804 ◽  
Author(s):  
Marisa M. Wall ◽  
Joe N. Corgan
Keyword(s):  
Field Study ◽  
Allium Cepa ◽  
Harvest Date ◽  
Harvest Time ◽  
Ambient Conditions ◽  
Fresh Market ◽  
Postharvest Losses ◽  
The Third ◽  
Short Day ◽  
And Storage

A 2-year field study was conducted to evaluate the effects of maturity and storage on fresh-market onion (Allium cepa L.) quality. Four short-day onion cultivars (`NuMex BR1', `NuMex Sunlite', `NuMex Starlite', and `Buffalo') were seeded in early October each year. Bulbs were harvested at five times; the first and second harvests were when 20% and 80 %, respectively, of the bulbs in a plot had mature necks; the third, fourth, and fifth harvests were at 5,10, and 15 days after the second harvest date, respectively. After curing for 3 days, bulb firmness, weight, and incidence of disease were evaluated for all harvests. Bulbs were re-evaluated after 10 and 20 days storage in a shed under ambient conditions. `Buffalo' and `NuMex Surdite' bulbs had the lowest incidence of disease before storage. For all cultivars, average bulb weight increased and firmness decreased with delayed harvest. Percent diseased bulbs increased for all cultivars as harvest was delayed in 1991 but not in 1992. The optimum harvest time was at 80% maturity. In storage, average bulb weight and firmness decreased, and the incidence of bulb diseases increased.

scholarly journals Quality Indices and Sensory Scores Support Early Harvest of Pecans

1995 ◽  
Vol 5 (3) ◽  
pp. 208-211
Author(s):  
Juan L. Silva ◽  
Frank B. Matta ◽  
Esteban A. Herrera
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Shear Force ◽  
Carya Illinoinensis ◽  
Sensory Properties ◽  
Harvest Time ◽  
Quality Indices ◽  
The Third ◽  
Hue Angle ◽  
Early Harvest

Pecans [Carya illinoinensis (Wangenh. C.) Koch] were harvested weekly for 9 and 7 weeks until normal harvest time during 1986 and 1987, respectively. Kernels were tested for chemical, physical, and sensory properties. Moisture decreased from 13% at initial harvest time to 4% to 6% by normal harvest. Free fatty acids decreased from 0.5% to 0.2% by the third week before normal harvest. Tannins fluctuated, but averaged about 0.8%. Hue angle remained constant from the fourth week to normal harvest. Shear force increased from 90 to 135 N by the second week before normal harvest. Pecans can be harvested about 2 weeks before normal harvest without significant quality deficiencies.

scholarly journals Modulating Fermentative, Varietal and Aging Aromas of Wine Using non-Saccharomyces Yeasts in a Sequential Inoculation Approach

2019 ◽  
Vol 7 (6) ◽  
pp. 164 ◽  
Author(s):  
Inês Oliveira ◽  
Vicente Ferreira
Keyword(s):  
Isoamyl Alcohol ◽  
Ethyl Esters ◽  
Wine Aroma ◽  
Torulaspora Delbrueckii ◽  
Sequential Experiments ◽  
Sequential Inoculation ◽  
Aroma Precursors ◽  
Pichia Kluyveri ◽  
Saccharomyces Yeasts ◽  
Lachancea Thermotolerans

The goal of this study is to assess to what extent non-Saccharomyces yeasts can introduce aromatic changes of industrial interest in fermentative, varietal and aged aromas of wine. Aroma precursors from Riesling and Garnacha grapes were extracted and used in two independent sequential experiments. Synthetic musts were inoculated, either with Saccharomyces cerevisiae (Sc) or with Pichia kluyveri (Pk), Torulaspora delbrueckii (Td) or Lachancea thermotolerans (Lt), followed by Sc. The fermented samples were subjected to anoxic aging at 50 °C for 0, 1, 2 or 5 weeks before an aroma analysis. The fermentative aroma profiles were consistently changed by non-Saccharomyces: all strains induced smaller levels of isoamyl alcohol; Pk produced huge levels of aromatic acetates and can induce high levels of fatty acids (FA) and their ethyl esters (EE); Td produced large levels of branched acids and of their EE after aging, and induced smaller levels of FA and their EE; Lt produced reduced levels of FA and their EE. The varietal aroma was also deeply affected: TDN (1,1,6-trimethyl-1,2- dihydronaphthalene) levels in aged wines were reduced by Pk and enhanced by Lt in Garnacha; the levels of vinylphenols can be much reduced, particularly by Lt and Pk. TD and Lt can increase linalool and geraniol in young, but not in aged wines.

Illusory Conjunctions of Color and Motion With Shape Following Bilateral Parietal Lesions

1998 ◽  
Vol 9 (3) ◽  
pp. 167-175 ◽  
Author(s):  
Lori J. Bernstein ◽  
Lynn C. Robertson
Keyword(s):  
Parietal Lobe ◽  
The Other ◽  
Feature Integration ◽  
Supporting Evidence ◽  
Spatial Representations ◽  
Brain Areas ◽  
Feature Representations ◽  
The Third ◽  
Illusory Conjunctions ◽  
Normal Feature

The primate visual system responds to shapes, colors, and various other features more strongly in some brain areas than others. However, it remains unclear how these features are bound together so that an object with all its attributes is perceived. A patient (R.M.) with bilateral parietal-occipital lesions has been shown previously to mis-combine the shape and color of items, making errors known as illusory conjunctions (ICs). In this study, we examined the effects of a third feature (motion) on this patient's IC rates. R.M. was presented with two letters that moved in different ways. He often reported seeing the shape of one of the letters with the other letter's motion. His performance on the same task with three features shows that correctly combining two features did not necessarily lead to correctly binding the third. These data support modularity of feature representations in the human brain and provide supporting evidence that spatial representations associated with the parietal lobe are necessary for normal feature integration.

scholarly journals The Effect of Non-Saccharomyces and Saccharomyces Non-Cerevisiae Yeasts on Ethanol and Glycerol Levels in Wine

Fermentation ◽  
2020 ◽  
Vol 6 (3) ◽  
pp. 77 ◽  
Author(s):  
Nedret Neslihan Ivit ◽  
Rocco Longo ◽  
Belinda Kemp
Keyword(s):  
Climate Change ◽  
Saccharomyces Cerevisiae ◽  
Chemical Composition ◽  
Flow Rate ◽  
Consumer Preferences ◽  
Harvest Time ◽  
Glycerol Content ◽  
Sequential Inoculation ◽  
The Impact

Non-Saccharomyces and Saccharomyces non-cerevisiae studies have increased in recent years due to an interest in uninoculated fermentations, consumer preferences, wine technology, and the effect of climate change on the chemical composition of grapes, juice, and wine. The use of these yeasts to reduce alcohol levels in wines has garnered the attention of researchers and winemakers alike. This review critically analyses recent studies concerning the impact of non-Saccharomyces and Saccharomyces non-cerevisiae on two important parameters in wine: ethanol and glycerol. The influence they have in sequential, co-fermentations, and solo fermentations on ethanol and glycerol content is examined. This review highlights the need for further studies concerning inoculum rates, aeration techniques (amount and flow rate), and the length of time before Saccharomyces cerevisiae sequential inoculation occurs. Challenges include the application of such sequential inoculations in commercial wineries during harvest time.

Nitrogen removal by an irrigated wooded buffer area

2011 ◽  
Vol 6 (3) ◽  
Author(s):  
Bruna Gumiero ◽  
Paolo Cornelio ◽  
Bruno Boz
Keyword(s):  
Organic Nitrogen ◽  
Nitrate Removal ◽  
Nitrogen Retention ◽  
Experimental System ◽  
Pilot Scale ◽  
Ammonia Nitrogen ◽  
First Year ◽  
Retention Capacity ◽  
The Third ◽  
Surface Water Flow

To demonstrate the efficiency of the wooded riparian soil in removing the exceeding nitrogen from the river water, a pilot-scale experimental system (0,8 ha) was planned and built on an area previously used to grow arable crops. It was constructed to allow the precise management of the system hydrology, because the water is electrically pumped from the adjacent Zero River into the irrigation ditches (ridges). The particular structure, characterized by ridges and furrows, facilitates sub-surface water flow through the woodland area and the creation of a suspended artificial aquifer seldom in contact with the groundwater. A grid of 36 piezometers was used to collect water samples. The results indicated that the nitrates retention capacity increased strongly from about 40 to 85% from the first to the third year. Ammonia nitrogen showed the highest annual variability, with the outputs in some cases exceeding the inputs. Organic nitrogen outputs were always higher than the inputs, but with a progressive reduction from the first to the third year. Overall, total nitrogen retention increased from 26% in the first year, to 62% in the third year. A monitoring campaign conducted after 8 year confirmed the long term efficiency of the site in nitrate removal with an increase also in organic nitrogen reduction.

scholarly journals Influence of Hanseniasporauvarum AS27 on Chemical and Sensorial Characteristics of Aglianico Wine

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 326
Author(s):  
Bruno Testa ◽  
Francesca Coppola ◽  
Silvia Jane Lombardi ◽  
Massimo Iorizzo ◽  
Francesco Letizia ◽  
...  
Keyword(s):  
Red Wine ◽  
Pilot Scale ◽  
Wine Production ◽  
Hanseniaspora Uvarum ◽  
Physical Chemical ◽  
Wine Composition ◽  
Sequential Inoculation ◽  
Aglianico Wine ◽  
Indigenous Yeasts ◽  
Sensory Profiles

In this work was evaluated the effect of sequential inoculum of Hanseniaspora uvarum AS27 strain and a commercial Saccharomyces cerevisiae yeast on the physical–chemical and organoleptic features of Aglianico, a traditional red wine of Southern Italy. Four fermentation treatments on a pilot scale were performed. In fermentation treatment A, the alcoholic fermentation was spontaneously conducted by the indigenous yeasts present in grape must. In the fermentation treatments B and C were inoculated respectively S. cerevisiae FE and H. uvarum AS27 strains, as a single starter. The fermentation treatment D was initially inoculated with H. uvarum AS27, and S. cerevisiae strain was added after 72 h (sequential inoculation). Microbiological, physical–chemical parameters and sensory profiles of the wines have been defined. The results showed that the use of H. uvarum AS27, in sequential inoculum with S. cerevisiae FE, influenced the wine composition, enriching it in polyphenolic and volatile compounds. Further, the sensory evaluation showed that the use of H. uvarum AS27 strain, in co-culture with S. cerevisiae, gives the wine more pleasant characteristics. Therefore, the results have highlighted how the use of particular non-Saccharomyces yeasts can represent a biotechnological resource in red wine production.

scholarly journals Impact of Lachancea thermotolerans strain and lactic acid concentration on Oenococcus oeni and malolactic fermentation in wine

OENO One ◽  
2021 ◽  
Vol 55 (2) ◽  
pp. 365-380
Author(s):  
Emma C. Snyder ◽  
Vladimir Jiranek ◽  
Ana Hranilovic
Keyword(s):  
Lactic Acid ◽  
Alcoholic Fermentation ◽  
Lactic Acid Production ◽  
Malolactic Fermentation ◽  
Oenococcus Oeni ◽  
Inhibitory Effect ◽  
Sequential Inoculation ◽  
The Impact ◽  
Lachancea Thermotolerans

The yeast Lachancea thermotolerans can produce lactic acid during alcoholic fermentation (AF) and thereby acidify wines with insufficient acidity. However, little is known about the impact of L. thermotolerans on Oenococcus oeni, the primary lactic acid bacterium used in malolactic fermentation (MLF). This study explored the impact of sequential cultures of L. thermotolerans and Saccharomyces cerevisiae on MLF performance in white and red wines. Four L. thermotolerans strains were tested in Sauvignon blanc with sequential S. cerevisiae inoculation, compared to an S. cerevisiae control and the initially un-inoculated treatments. The L. thermotolerans wines showed large differences in acidification, and progression of MLF depended on lactic acid production, even at controlled pH. The highest and lowest lactic acid producing strains were tested further in Merlot fermentations with both co-inoculated and sequentially inoculated O. oeni. The low lactic acid producing strain enabled successful MLF, even when this failed in the S. cerevisiae treatment, with dramatically quicker malic acid depletion in O. oeni co-inoculation than in sequential inoculation. In contrast, a high lactic acid producing strain inhibited MLF irrespective of the O. oeni inoculation strategy. In a follow-up experiment, increasing concentrations of exogenously added lactic acid slowed MLF and reduced O. oeni growth across different matrices, with 6 g/L of lactic acid completely inhibiting MLF. The results confirm the inhibitory effect of lactic acid on O. oeni while highlighting the potential of some L. thermotolerans strains to promote MLF and the others to inhibit it.

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