AW4 is noted for developing powerfully fragrant, full spice aromatic wines and is a perfect match for Gewurztraminer and also recommended for Sauvignon and Semillon where the Oenologist requires a positive aromatic esters contribution from the yeast. AW4 is a good fermenter across the range 14 to 30°C (57 -86°F), low foam formation and medium to high glycerol. It will ferment up to 14.5% abv. ethanol providing the temperature is held within the 20 - 25°C (68 -77°F) range and the pH is above 3.0.

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.

Saccharomyces Cerevisiae – Acid reducing strain excellent for fruity white & blush country wines especially where residual sugars are desired. MA33 has the ability to metabolize between 30 and 35% of malic acid making this strain the perfect choice for country fruits which are naturally high in acid. Reducing malic acid will soften the wine and give a vin nouveau character for early consumption with a balanced palate. MA33 is also noted for its production of fruity esters and fusel oils conferring fresh fruity character to the wine. There is an increased chance of Malolactic fermentation by lactic acid bacteria following MA33 fermentation. MA33 is a killer-sensitive strain. It is a good fermenter between 18 and 27°C (64 -80°F), with a rapid onset to fermentation although can exhibit a slow late fermentation profile and may require aeration after 10 – 12 days fermentation. Will ferment up to 14% abv. ethanol providing the pH is above 3.2.

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 30°C (72 -86°F) which will ferment to 13.5% abv. ethanol.

Saccharomyces Cerevisiae - Perfect for sweet white/blush and dessert wines from grape and particularly from country fruits & flowers. CY17 produces high levels of desirable congeners during fermentation including aromatic thiols, imparting rich fruity aromatics, full body and ‘tropical’ flavour characteristics to the wine. CY17 is also noted for high glycerol formation further enhancing sweetness. This is a slow fermenter compared to all other strains in the Vintner’s Harvest range typically taking up to 21 days to ferment table wines and up to 35 days for dessert wines. CY17 prefers a constant temperature in the 22 – 26°C (72 -78°F) range. Dropping the temperature below 15°C (59°F) two-thirds the way through fermentation will arrest fermentation making CY17 suitable for producing naturally sweet wines (both potassium sorbate and metabisulphite must be used to prevent re-fermentation). CY17 is also excellent for sweet sparking wines, but strain CL23 must be employed for the bottle fermentation stage. Avoid free SO2 levels above 50 ppm and ensure pH above 3.2, CY17 is a delicate strain that must be treated with some respect. Pay particular attention to sterile winemaking conditions and a warm start to fermentation otherwise risk of bacterial contamination is increased. CY17 will happily ferment up to 15% abv. ethanol if such conditions are employed.

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 30°C (72 -86°F) which will ferment to 13.5% abv. ethanol. Low to medium foaming strain with low volatile acid and SO2 production.

Saccharomyces Cerevisiae – Ideal for full bodied, full flavoured dry and sweet white wines. BV7 will both preserve and enhance the grape variety and terroir, promoting excellent flavour complexity, good wine structure and balance but especially FULL AROMATIC FLAVOUR. To appreciate the impact of BV7, split a chardonnay must, fermenting half with CL23 and the remainder with BV7 – you will be amazed at the impact of the yeast strain upon fruit concentration. BV7 produces a wide range of low level beneficial congeners such as higher alcohols and esters and high glycerol promoting full body and structure to the wine and contributing significantly to mouth-feel, wine texture and palate intensity. Avoid fermenting above 13% abv. ethanol, BV7 is not particularly ethanol tolerant. Acceptable temperature range is 15 to 30°C (59 -86°F) but ferment below 22°C (72°F) for maximum flavour development.

Saccharomyces Bayanus – Ideal for crisp, fresh dry white/blush and all sparkling wines. Also the best strain for high alcohol tolerance. CL23 produces very low levels of fusel oils and other congener compounds during fermentation and so does not contribute much to wine flavour or aroma and can therefore be considered to be a particularly neutral / clean fermenter. However CL23 does contribute significantly to the wines structure and ferments out sugars completely allowing for the driest of wines to be made. CL23 is 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 making CL23 the strain of choice for high alcohol wines or where uncertain recipes are employed and fermentation reliability is a key factor or where low temperature fermentation down to 8°C (46°CF) 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. In certain situations, CL23 can be used for red winemaking – especially where wine structure and dryness are key factors – but a word of caution, CL23 will take out colour and fruit flavour so recipes should be adjusted accordingly. To appreciate such attributes, split a Cabernet Sauvignon Must and ferment out using CL23 versus VR21 – you will not believe both wines came from the same grape.