Active Yeast 7
SIHA Active Yeast 7 (Riesling Yeast) is a pure, highly active dry concentrate of natural wine yeast isolated from German Riesling must, known for its excellent fermentation performance.
Technical Specifications
SIHA Active Yeast 7 (Riesling Yeast) produces particularly fruity and typical Riesling wines. The character of the wine is clearly distinguishable in a clear bouquet depending on the vine sort and vineyard location. SIHA Active Yeast 7 (Riesling Yeast) produces no unwanted fermentation side products such as SO2, H2S, acetaldehyde, pyruvic acid (pyruvate), α-ketoglutaric acid, volatile acids, and esters.
The yeast can produce up to 16% alcohol by volume. The practical alcohol yield is approximately 47% of the sugar content. For each lb (kg) of sugar fermented, approximately 247 kJ (59 kcal) of heat is released. SIHA Active Yeast 7 (Riesling Yeast) forms extremely small quantities of glucane and urethane during fermentation.
Features and Benefits
The specific advantages of SIHA Active Yeast 7 (Riesling Yeast):
- Carefully selected over many years in order to obtain the typical Riesling character
- Capability to produce very varied wines because the typical bouquet of the sort and location is accentuated
- Negligible frothing
- Rapid fermentation start
- Little formation of unwanted fermentation side products (SO2, acetaldehyde, volatile acid, H2S, ester)
Product Applications
The musts in each single fermentation drum should be treated with SIHA Active Yeast 7 (Riesling Yeast) in good time. Longer periods of standing favor the uncontrolled reproduction of wild yeasts and unwanted bacteria.
The optimum fermentation temperature is 59 – 72°F (15 – 22°C). A starting and fermentation temperature of at least 50°F (10°C) is necessary.
SIHA Active Yeast 7 (Riesling Yeast) is best stirred into 10 times the amount of a fifty-fifty must-water mixture at 68 – 86°F (20 – 30°C), left for about 10 minutes, then stirred thoroughly again and added to the must. SIHA Active Yeast 7 (Riesling Yeast) can also be added directly to the must without suspension. The period until fermentation begins is only extended by a few hours as a result.
However, to ensure reliable fermentation, the yeast quantity should be increased by about 20%. The addition of 0.005 lb SIHA Vitamin B1 yeast nutrient fermentation aid per 1,000 gal (600 mg per 1,000 L) creates even better fermentation and metabolic conditions. To complete the fermentation of stopped wines, the addition of 1.3 lb/1,000 gal (15 g/hL) SIHA Fermentation Salt yeast nutrient fermentation aid (diammonium phosphate) is recommended.
For best results, it is advantageous to let the yeast become accustomed to the fermentation conditions. This is done by adding the yeast quantity required for the whole amount of wine to about 10% of the material for fermentation until about half of the sugar present has been used up. Then this mixture is added to the remaining 90% of the wine to be fermented.
