New yeast strains isolated
New strains of wine yeast are continuously being isolated and adopted by commercial vineyards but, as with so much regarding winemaking, they remain a closely guarded secret. Vintner’s Harvest entered into an exclusive yeast strain screening program with a leading yeast and ingredient supplier to the European commercial winemaking industry. This program considered only specialist wine yeast strains used commercially in Europe and identified a complete wine yeast range for all varieties of Grape, Fruit and Vegetables. The screening process involved 3,000 separate fermentations over a two year period.
VR21 Saccharomyces Cerevisiae
Exceptional strain for full fruit varietal and country red wines promoting good structure, balance and colour. The majority of yeast strains strip out fruit flavour and colour from the must, not so with VR21 which is particularly noted for preserving and retaining the natural fruit characteristics of the grape / country fruit and enhancing palate length. VR21 is a relatively neutral strain producing subtle levels of aroma and flavour compounds, allowing full expression of varietal / country characteristics whilst enhancing colour, wine structure and balance. VR21 is an ethanol tolerant killer strain, capable of fermenting to 15% abv. ethanol. Good production of glycerol, low volatile acid production, zero sulphur dioxide formation and low foaming.
R56 Saccharomyces Cerevisiae
Ideally suited for rich, full bodied red wines with exceptional flavour complexity. Noted for exceptional depth and flavour complexity, R56 exhibits complex aromatics during fermentation conferring an old world
quality which one might only expect from natural flora multiple strain fermentations. Unusually for complex aromatic strains, R56 still respects the varietal character of the fruit and confers good structure and balance. R56 is also a high glycerol producing strain. R56 is a medium rate fermenter with optimal temperature between
22 to 30OC (72 -86OF) which will ferment to 13.5% abv. ethanol.
CR51 Saccharomyces Cerevisiae
Perfect for light, fruity red wines for early consumption CR51 will enhance ripe berry fruit flavours in light and fruity red wines and introduce a velvet texture perfect for Valpolicella and especially for Beaujolais style wines. This strain has an almost unique ability to confer a smooth even ‘silky’ quality to the wine, perfect for early
consumption young reds. CR51 is a medium rate fermenter with optimal temperature between 22 to 30OC (72 -86OF) which will ferment to 13.5% abv. ethanol. Low to medium foaming strain with low volatile acid and SO2 production
SN9 Saccharomyces Bayanus
Very good all round strain, best choice for high alcohol and fortified wines but also excellent for most country
wines, sweet sparkling wines and ciders. If you only had one wine yeast strain, this would be the strain because whilst being relatively neutral in character SN9 does introduce excellent weight and structure no matter the must or fruit and produces a congener profile that always compliments the wine. SN9 is particularly good when fermenting flower or low fruit recipes which often lack vinosity, weight and depth. SN9 is another strain noted for its robustness, being able to ferment to 18% abv. ethanol, tolerate high free SO2 and high levels of other
stress factors such as organic acids, incorrect temperature and pH. But unlike CL23, SN9 adds weight and high glycerol production making the strain perfect for high alcohol sweet wines or where uncertain recipes are employed and fermentation reliability is a key factor or where low temperature fermentation down to 10OC (50OF) is required. This strain is ‘fermentation friendly’ in that it produces zero foam, starts fermenting rapidly so avoids potential bacterial contamination and can be used to re-start stuck fermentations. SN9 is also the
most osmotolerant and the fasting clearing of all Vintner’s Harvest strains.
