Brewers Yeast For Animals & Aquaculture Feed

Specification

English Name:Brewers yeast, brewer's yeast, top-fermenting yeast, brewers' dried yeast, brewers' yeast dehydrated

Description :

Brewers yeast is a by-product from the breweries, which use the micro-organism and fungal yeast Saccharomyces cerevisiae. Brewers yeast is obtained by the removal of yeast after the brewing process and subsequent inactivation by means of organic acids. Brewers yeast is used as a flavouring ingredient in the food industry, and as feedstuff for pigs, ruminants, poultry and fish. Brewers yeast is mainly a source of protein, vitamins and minerals . Yeast inactivation is necessary to prevent further fermentation after consumption by animals, that may cause severe gastro-intestinal problems in pigs. Inactivated brewers yeast is a highly valuable source of protein, phosphorous and B vitamins. Brewers yeast may be fed fresh (liquid form) or dried (brewers dried yeast), which is costly and thus only used in specialty feeds.

Processes:

Storage:

Brewers yeast has a limited shelf-life and may suffer tremendous losses of total solids during storage. Live yeast in storage are prone to contamination : they consume their glycogen reserves which makes them more susceptible to rupture and can result in the release of their content in the liquid phase where bacteria can feed off the nitrogen released, and multiply rapidly.  So the yeast slurry needs to be as contamination free as possible when stored. Cold temperatures can help retard bacterial growth. Chilling prevents yeasts from losing their cell constituents (i.e. protein) as a result of cell autolysis at ambient temperatures. To prevent these losses, it is necessary to chill yeast slurry to below 5°C 

Inactivation

Beer production yields 5 times more yeast than the amount required for beer processing . At the end of the process the yeast is removed from the batch by centrifugation, and then washed free of beer. It is still alive and could have deleterious effects during storage or when fed to animals.

It is thus necessary to inactivate it before using it. This can be done through heat treatment (80°C at the brewery) and/or by addition of organic acids on the farm . Brewers yeast contains valuable components such as ribonucleic acid (RNA) and vitamin D, which can be extracted before the yeast is sold fresh to farmers, feed companies or the food industry

Removal of bitterness

If the yeast contains hop residues, it may have a bitter taste that makes the feed unpalatable if included in large amounts. The bitter taste can be removed by mixing the slurry with a solution of sodium hydroxide and sodium phosphate that raises the pH to 10, after which the mixture is concentrated, washed and dried 

Drying

Yeast is usually drum-dried, which requires expensive machinery and energy. The process is economical only in large breweries. The yeast can also be mixed with brewer’s grains and dried as a mixture in a steam-tube drier. This method increases the value of the spent grain. Brewers dried yeast has to be ground after drying 

Active Dry Yeast Feed yeast, used as yeast organisms feed for livestock and poultry. Includes all single-cell proteins produced with single-cell microorganisms. Light yellow or brown powder or granules with high protein content and rich in vitamins