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Nottingham

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  • A relatively neutral ale yeast, capable of medium-high attenuation. Has high flocculation rate, and can reach ABV of 11%-13% in normal conditions, 18% when adding Fermaid-K as fermentation progresses. Fast fermentations, frequently done in under 48 hours.
  • Great for making British style ales. A good all rounder one of the best if you do not need a particular taste profile from a yeast. Being a dry yeast there is no need to make a starter.
  • It produces low concentrations of fruity and estery aromas and has been described as neutral for an ale yeast, allowing the full natural flavor of malt to develop. Good tolerance to low fermentation temperatures, 14°C (57°F), allow this strain to brew lager-style beer. Recommended 14° to 21°C (57° to 70°F) fermentation temperature range.

1. Origin

Nottingham British Ale yeast is a single strain selected from a multiple commercial culture used in the United Kingdom. The propagation and drying processes have been specifically designed to deliver high quality beer yeast that can be used simply and reliably to help produce ales of the finest quality. No colours, preservatives or other unnatural substances have been used in its preparation. The yeast is produced in ISO 9002 certified plants.

2. Microbiological Properties

• Classified as Saccharomyces cerevisiae. • A top fermenting yeast. • The typical analysis of the active dried strain: Percent solids 93%–95% Living yeast cells ≥ 5 x 109 per gram of dry yeast Wild yeast < 1 per 106 yeast cells (Lysine method)* Bacteria < 1 per 106 yeast cells* • Finished product is released to the market only after passing a rigorous series of tests.

  • According to ASBC and EBC methods of analysis.

3. Brewing Properties

• Quick start to fermentation, which can be completed in 4 days above 17°C. • High attenuation, reaching a final gravity near 1008 (2°P). • Fermentation rate, fermentation time and degree of attenuation is dependent on inoculation density, yeast handling, fermentation temperature and the nutritional quality of the wort. • Shows flocculation at completion of fermentation, and settling is promoted by cooling and use of fining agents and isinglass. • The aroma is slightly estery, almost neutral and does not display malodours when properly handled. Because of flocculation, it may tend to slightly reduce hop bitter levels. • Best when used at traditional ale temperatures after rehydration in the recommended manner. • Lager-style beer has been brewed with Nottingham, however low fermentation temperature requires adaptation of the pitching rate to ensure proper attenuation.

4. Usage

• When 100 g active dried yeast is used to inoculate 100 litres of wort, a yeast density of 5–10 million cells per millilitre is achieved. Brewer may experiment with the pitching rate to achieve a desired beer style or to suit processing conditions. • Sprinkle the yeast on the surface of 10 times its weight of clean, sterilized (boiled) water at 30–35°C. Do not use wort, or distilled or reverse osmosis water, as loss in viability will result. DO NOT STIR. Leave undisturbed for 15 minutes, then stir to suspend yeast completely, and leave it for 5 more minutes at 30–35°C. Then adjust temperature to that of the wort and inoculate without delay. • Attemperate in steps at 5-minute intervals of 10°C to the temperature of the wort by mixing aliquots of wort. Do not allow attemperation to be carried out by natural heat loss. This will take too long and could result in loss of viability or vitality. • Temperature shock, at greater than 10°C, will cause formation of petite mutants leading to long-term or incomplete fermentation and possible formation of undesirable flavours. • Nottingham British Ale yeast has been conditioned to survive rehydration. The yeast contains an adequate reservoir of carbohydrates and unsaturated fatty acids to achieve active growth. It is unnecessary to aerate wort.

5. Storage

• All active dried yeast should be stored dry and below 8°C. The packaging should remain intact. • Activity loss is about 25% per year at 8°C and 50% per year at 22°C in unopened sealed packs. • Nottingham will rapidly lose activity after exposure to air. Do not use 500 g or 10 kg packs that have lost vacuum. Opened packs must be re-closed, stored in dry conditions below 4°C, and used within 3 days; 11 g sachets are not vacuum packed but are flushed with nitrogen gas to protect the yeast. • Do not use yeast after expiry date printed on the pack.