Alcohol recovery from yeast

Spent yeast from alcoholic fermentations (wine, beer cider etc) contains a significant alcohol content associated with the liquid not only around the yeast but also in the cell contents. With today’s current focus on cost management and environmental control of manufacturing, many companies are looking at recovering as much alcohol as possible from their fermentation process.

Even if a brewer or winemaker takes primary steps to recover beer or wine using centrifuges or filtration technology, the residual yeast from these processes will still contain significant alcohol. This alcohol can potentially be recovered to produce a useful spirit ingredient and at the same time reducing a known effluent problem.

Due to it’s unique internal design the Spinning Cone Column (SCC) can be used to recover alcohol directly from yeast broth or slurry continuously and efficiently.
 
Beer/Wine yeast with a dry matter content of up to 15% can easily be processed through the SCC system in a single continuous pass in order to recover greater than 90% of the alcohol present. The strength of the alcoholic condensate will largely depend on the strength of the feed material. As an example, for a feed of brewers yeast at 7.5%abv, a condensate strength of 45%abv would be typical. For wine yeast (lees) at 14%abv alcoholic condensate would be collected at 60%abv.

Apart from significantly reducing effluent problems associated with residual alcohol, the alcoholic condensate can be used as an ingredient in other alcoholic beverage formulations or sold as a by product.

Bio ethanol produced from yeast fermentation can be obtained directly from the fermentation broth using the SCC. This removes the necessity to separate yeast from liquid as would normally be required when using conventional continuous stripping technology. In this case rectification of the alcoholic condensate from the SCC is desirable to increase the alcoholic strength.
 
Benefits of the SCC system for recovering alcohol from yeast include:

• High quality alcohol spirit obtained
• High alcohol yield 
• No separation of yeast necessary to allow processing
• Low energy consumption
• High level of hygiene with proven CIP process 
• Flexibility of system (same system can be used for yeast and also de-alcoholisation of beer and wine)
• Continuous and intensive process 
• Compact design due to mass transfer efficiency
• Modular design
• Plant supplied as factory tested, complete modules
• Yeast integrity/viability maintained due to gentle process