SafŒno™ UCLM S377

Available in 500g and 10kg packaging.


For long ageing and fruity red wines

SafŒno™ UCLM S377 was selected by the Castilla La Mancha University for its ability to produce very structured long ageing red wines.

Still wines. Dosage: 20 g/hl
Fermentation restart. Dosage: 30 to 40 g/hl

Ingredients: yeast (Saccharomyces cerevisiae*), Emulsifier E491 (sorbitan monostearate)

SafŒno™ UCLM S377 sensory features

For mediterranean style varieties

SafŒno™ UCLM S377 was selected for its respect of the terroir & varietal character. It allows increasing varietal characteristics of Syrah, Mourvèdre, Tempranillo and Grenache, and other sun-kissed varieties.

For premium red wines

SafŒno™ UCLM S377 gives excellent results for full-bodied but well-balanced wines. Its rather slow fermentation kinetic is very convenient for wines incurring a fermentation maceration of over 10 days allowing the wine maker to elaborate finely structured wines. Indeed, during the fermentation the progressive alcohol production is favorable to a good polyphenolic extraction.
Wines produced present an excellent ageing capacity (Tempranillo de Crianza, Cabernet Sauvignon, Syrah) and have an important volume thanks to SafŒno™ UCLM S377’s high glycerol production.

  • Gently pour the desired quantity of yeast in 10 times its weight of tap water at 30-35°C in a wide vessel. Pay attention to cover all the water surface area by creating a thin layer of yeast.
  • Leave to rest for 20 minutes.
  • Gently stir to complete yeast rehydration while avoiding the formation of lumps prior acclimatization.
  • Double progressively the volume of the yeast suspension by adding must from the tank while stirring the mix so that the temperature of the yeast starter decreases and yeast activation starts.
  • Leave to rest for 10 minutes.
  • Homogenize and incorporate the yeast starter in the fermentation tank during a pumping over with aeration.

SafŒno™ UCLM S377 technical features

→ Rapid fermentation start
→ Rather slow fermentation kinetic
→ Total loss of sugars
→ Alcohol tolerance: 14-15 % vol./vol.
→ Fermentation temperature: 16 to 35°C. This strain is sensitive to brutal temperature changes, it requires regular fermentation conditions.
→ High nitrogen requirement: In a must which available nitrogen is between 150 and 180 mg/L this strain requires at least 2 nitrogen supplies (20g/hl DAP + 20g/hl Springferm™ at yeast inoculation and 20g/hl of DAP and Springferm™ between the third and mid-fermentation.
→ Strong resistance to SO2

→ Sugar/Alcohol yield: 16.5 g/L for 1% vol./vol.
→ Low production of volatile acidity (< 0.25 g/L) and of acetaldehyde (<28 mg/L)
→ No production of sulfur compounds
→ High production of glycerol : 10 g/L

  • Lesaffre know-how and continuous yeast production process improvement lead to obtain an exceptional quality of dry yeasts able to resist to a very wide range of use, cold or no rehydration included, without affecting their viability, kinetic and/or analytical profile.Winemakers can choose usage conditions that fit the best their needs, i.e.:
    • Direct inoculation: Pour the yeast on the surface of at least 10 times their weight of must (possibly directly on the top of the tank or during tank filling after settling for whites and rosés). Gently stir to avoid or break clumps. Immediately transfer into the tank via a pumping over with aeration (or homogenize tank volume).
    • With prior rehydration: Pour the yeast on the surface of 10 times their weight of tap water at room temperature. Gently stir to avoid or break clumps. Wait for 20 minutes and transfer into the tank via a pumping over with aeration.


Carton of 20 vacuum-packed sachets of 500g each (Full box net weight: 10 kg).
Carton of 1 vacuum-packed box of 10 Kg (Full box net weight: 10 kg).


The high rate of dry matter of our yeasts assures an optimum storage in its original packaging at a temperature not higher than 20°C (during 3 years) and 10°C for an extended storage (4 years). Fermentis guarantees the product complies with the International Oenological Codex until its Best Before End Date in the storage conditions mentioned above.

Each Fermentis yeast is developed under a specific production scheme and benefits from the know-how of the Lesaffre group, world leader in yeast manufacturing. This guarantees the highest microbiological purity and maximum fermentation activity.

The data contained in this technical sheet are the exact transcription of our knowledge of the product at the mentioned date. They are the exclusive property of Fermentis-Division of S.I.Lesaffre. It is of the user responsibility to make sure that the usage of this particular product complies with the legislation.

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