Enology – Non-Saccharomyces Yeasts in Fermentation Session

Anne Flesch* | Julian Pietersen | Benoit Divol | Stéphanie Rollero

Innovative Applications in Winemaking: Yeast Derivatives as Functional Lipid Sources

Anne Flesch,* Julian Pietersen, Benoit Divol, and Stéphanie Rollero

*Fermentis, 7475 W Main St, LYC, Milwaukee, WI, 53214, a.flesch@fermentis.lesaffre.com

Climate change brings multiple challenges to the wine industry, including higher sugar/alcohol content, lower acidity, and imbalances in yeast nutrients. Winemaking practices such as low-temperature fermentations and excessive clarification of white grape to produce fruitier wines in response to consumer demand may create conditions leading to sluggish or stuck fermentations. These challenging conditions can be overcome by Saccharomyces cerevisiae by enriching its membrane composition in fatty acids and ergosterol. However, in the absence of oxygen, the yeast cannot produce the necessary lipids and therefore relies on those occurring in grape must or by supplementation. Until recently, only products derived from S. cerevisiae have been permitted, which limits the scope of use and the efficacy of these products. Recent changes allowing use of non-Saccharomyces yeasts offers an opportunity to tap into their composition diversity (Mbuyane 2021). In this work, a wide selection of non-Saccharomyces yeasts isolated from the broader wine environment were screened for their lipid content. Six strains were selected based on the quantity and diversity of lipids produced. In the next step, inactivated dry yeasts were produced from these innovative yeasts and tested as lipid supplements in over-clarified Chenin blanc juice. The addition of inactivated yeasts enhanced fermentation performance compared to the reintroduction of fine lees and the control with no addition. Furthermore, experiments with addition of pure analytical standard lipids in the same concentrations yielded similar results, correlating the change in fermentation kinetics to the lipid additions. Overall, the data showed that novelty derivatives from diverse yeasts may serve as a sustainable improved source of nutrient for fermentation under challenging conditions. The work also paves the way for further research on the selection, optimal production, and use of new lipid rich yeast derivatives for wine fermentations.

Mbuyane: DOI: 10.1016/j.foodres.2021.110142

Funding Support: 1. Fermentis by Lesaffre, 90 rue de Lille, 59520 Marquette-Lez-Lille, France 2. South African Grape and Wine Research Institute, Stellenbosch University, Private bag X1, Matieland, 7602, South Africa

Valentina Martin | Eduardo Boido | Maria Jose Valera | Karina Medina | Gonzalo Baldivia |
Karen Perelmuter | Luisa Vivian Schwarz | Adelaide Gallo | Laura Farina | Mariela Bollati-Fogolin |
Remi Schneider | Eduardo Dellacassa | Antonio Morata | Francisco Carrau*

Fast Yeast Lysis in Hanseniaspora vineae: Increasing White Wine Complexity and Mouthfeel in Days Instead of Months

Valentina Martin, Eduardo Boido, Maria Jose Valera, Karina Medina, Gonzalo Baldivia, Karen Perelmuter, Luisa Vivian Schwarz, Adelaide Gallo, Laura Farina, Mariela Bollati-Fogolin, Remi Schneider, Eduardo Dellacassa, Antonio Morata, and Francisco Carrau*

*Universidad De La Republica Uruguay, School of Chemistry, Enology Area., Av. Gral. Flores 2124, Montevideo, 11800 Montevideo, Uruguay, fcarrau@fq.edu.uy

Yeast-derived compounds released during lees contact play a central role in wine mouthfeel, stability, and aroma development, but conventional autolysis of Saccharomyces cerevisiae typically requires several months under barrel, tank, or bottle aging conditions. We evaluated the lysis behavior of the non-Saccharomyces yeast Hanseniaspora vineae during white wine fermentations and compared it with commercial Saccharomyces strains under identical conditions. The objective was to determine whether species-dependent differences in cell stability can significantly modify the timing of intracellular compound release and therefore affect wine texture and sensory development. Flow cytometry confirmed that fermentations conducted in model grape medium and Chardonnay must showed that H. vineae undergoes rapid loss of membrane integrity, accumulation of reactive oxygen species (ROS), and cell lysis within days at the end of alcoholic fermentation, while S. cerevisiae maintains cell integrity and delays autolysis for months. Interestingly, it was confirmed that this fast lysis phenotype is species-specific and is not observed in Hanseniaspora uvarum. Further genomic studies may explain this characteristic of some Hanseniaspora species. Rapid cell breakdown in H. vineae fermentations was associated with earlier release of polysaccharides and mannoprotein-rich material, as well as medium chain fatty acids, amino acids, short peptides, and nucleic acid derivatives into the wine matrix. From an enological perspective, this accelerated release pattern enhanced mouthfeel, palate volume, and aromatic complexity in a significantly shorter timeframe, potentially reducing the need for prolonged lees aging and extended barrel or bottle storage. This approach may help lower production time and cost while reducing risks associated with over-aging or excessive oak impact. The effect is relevant not only for premium white varieties such as Chardonnay, Viognier, Chenin blanc, Albariño, and Albillo, but also for large-volume tank-fermented wines including Glera, Trebbiano, Macabeo, and Airén, where faster development of lees-derived attributes can provide technological and economic advantages.

Funding Support: Agencia Nacional de Investigación e Innovacion ANII Universidad de la Republica, Uruguay Lage y Cia S.A., Uruguay Oenobrands, France

Amanda Fleming | Renee Threlfall* | Erich Leitner

Assessing Aroma of Chambourcin Wines Produced with Different Strains of Lachancea thermotolerans Yeast

Amanda Fleming, Renee Threlfall,* and Erich Leitner

*University of Arkansas, Food Science Department, 2650 N. Young Ave, Fayetteville, AR, 72704, rthrelf@uark.edu

Using non-Saccharomyces yeasts can enhance wine quality and complexity. Lachancea thermotolerans (LT) aids in pH reduction during fermentation and can improve a wine’s aroma profile. In 2024, 263 kg of Arkansas-grown Chambourcin (Vitis hybrid) grapes were hand-harvested, randomized into batches, processed, and fermented. Seven inoculation treatments, in duplicate, were conducted using Saccharomyces cerevisiae (SC) and three LT strains, including a commercial strain (Laktia™) and two experimental strains (LT₁ and LT₂), receiving sequential SC inoculations after 24 or 48 hr. All treatments were co-inoculated with malolactic bacteria 24 hr after inoculation with SC. Volatile compounds were analyzed at bottling via solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). There were 86 volatile compounds identified, comprised of esters (29), higher alcohols (21), acids (10), aldehydes (10), ketones (10), terpenes (2), acetals (1), glycols (1), lactones (1), and sulfides (1). Total volatiles ranged from 45,401 ug/L (Laktia-SC-24 hr) to 77,641 ug/L (LT₁-SC-24 hr). LT₁-SC-24 hr wines had the highest total volatile concentrations compared to other treatments. All treatments were dominated by esters and higher alcohols; however, LT wines showed higher total esters and alcohol concentrations at 24 hr compared to 48 hr sequential inoculation. Principal component analysis indicated that SC wines were associated with fruity, tropical, herbal, green, and fermentation-related esters and higher alcohols. Laktia wines, regardless of inoculation timing, were linked to higher alcohols, esters, terpenes, and aldehydes contributing floral, citrus, and green aromas. LT₁-SC-24 hr and LT₂-SC-24 hr wines were associated with esters and higher alcohols, while LT₁-SC-48 hr was dominated by esters and ketones and LT₂-SC-48 hr by higher alcohols. Overall, LT fermentations shifted aromatic composition and increased potential complexity compared to S. cerevisiae-only wines, with sequential inoculation timing playing a key role within each strain.

Funding Support: Lallemand Enology

Charlotte Drop | Sean Kuster | Biljana Petrova | Robert Coleman | Miguel Pedroza | Federico Casassa*

Effects of Skin Contact and Acid Management Strategies on Grüner Veltliner Wines from the Central Coast of California

Charlotte Drop, Sean Kuster, Biljana Petrova, Robert Coleman, Miguel Pedroza, and Federico Casassa*

*Wine and Viticulture Department, Cal Poly San Luis Obispo, Justin and J. Lohr Center for Wine and Viticulture, Building 156, Office 116, 1 Grand Avenue, San Luis Obispo, CA, 93407, lcasassa@calpoly.edu

Grüner Veltliner wines from the Central Coast of California were produced under three treatments in addition to a control: skin contact, fermentation with the lactic acid-producing Lachancea thermotolerans (Omega strain), and ion exchange (IE) treatment of juice followed by blending at a 30% proportion before alcoholic fermentation (AF). Control and skin contact had similar average oxidation-reduction potentials during AF (-82 and -81 mV, respectively). Compared to the control, skin contact increased pH by 0.11 units and decreased titratable acidity (TA) by 0.71 g/L, while also increasing total phenolics by 324%, potassium by 12.2%, and hue. Lachancea produced 4.75 g/L of lactic acid and was most effective at increasing TA (11.07 g/L versus 6.87 g/L in the control). Lachancea wines had the highest odor activity values for ethyl butyrate, isoamyl acetate, and hexyl acetate (38, 82, and 92% more than the control). Skin contact wines had the highest ethyl cinnamate (1092% higher than the control), while Lachancea and 30% IE juice wines increased trans-nerolidol by 26% and 22%, and geraniol by 62% and 71%, respectively, compared to the control. The 30% IE juice wines decreased potassium by 9% compared to the control and were most effective at lowering pH, reducing it by 0.32 units. 30% IE juice wines had higher tartaric acid concentrations (4.06 g/L versus 2.68 g/L in the control), indicating improved tartrate stability. In contrast, skin contact wines had less tartaric acid (2.14 g/L), likely due to higher potassium concentrations. Pivot profile sensory analysis showed that skin contact wines had more bitterness and resinous aromas, Lachancea wines had the highest overall aroma intensity with more banana and citrus aromas, and 30% IE juice wines had the most perceived acidity and apple aroma.

Funding Support: Ryan Scott Williams (Monterey Pacific Vineyards) and Treasury Wine Estates (St. Helena, California, USA) are thanked for their donation of fruit and logistical support, respectively.