As a leavening agent, yeast converts sugar in the dough to carbon dioxide. The dough rises because of the bubbles of carbon dioxide becoming trapped during baking.
With our technology, baker’s yeast can be produced from a variety of raw materials containing sugar or starch. Mixtures of cane and beet molasses are the best choice for top product quality. Owing to circumstances, the sugars from molasses may be replaced by other sugar sources, such as hydrolysates from starch or even stale bread.
Vogelbusch process for baker's yeast production
The complete yeast production line comprises the following process groups
Additionally, waste water treatment is a necessity at most sites.
Molasses is purified either by sedimentation or by mechanical separation. The clarified molasses is sterilized and then mixed in the fermentors with nutrients, trace elements and vitamins or, in fed batch fermentation, slowly added as required.
Auxiliaries such as urea, phosphate and magnesium salts are dissolved in tanks. Sulfuric acid and phosphoric acid are diluted and prepared for the various process steps.
Our yeast culture collection contains hundreds of different baker’s yeast strains. The most suitable yeasts are selected carefully from our strain collection to provide the best rising power for the respective raw material and application.
Choosing the ideal yeast strain is a prerequisite for baking yeast with high driving power and for a high quality product.
The propagation of yeast passes through several stages. Yeast inoculum is cultivated in the laboratory. It is used to seed the pure culture fermenter. Via a pre-fermentation, the resulting yeast suspension is fed to the seed yeast fermenter. The seed yeast is separated and stored in a tank.
For commercial yeast production, the prepared fermenter is inoculated with a portion of seed yeast. After about 24 hours, the fermentation is completed and the yeast is separated off and washed.
Up to eight production fermentations can be started with one lot of seed yeast.
Commercial yeast is separated from the fermentation broth by nozzle separators. It is washed with process water and filtered to increase the dry matter content of the resulting yeast cream.
For wet compressed yeast, the filtered yeast cream passes through an extruder, and is pressed and cut into wet yeast blocks. These are packed, and need to be cold stored until use.
To produce instant active dry yeast (iADY), it is first mixed with an emulsifier and pressed into fine strands in an extruder. The extruded yeast is carefully dried with hot air, transferred into silos and packaged airtight.
Baker's yeast products manufactured with Vogelbusch technology have different characteristics
wet yeast |
iADY |
|
| Dry matter content (DS) | 28 to 34 % | 92 to 98 % |
| Shelf live | up to 4 weeks | 2 years and more |
| Storage conditions | refrigerated | room temperature |
We design our plants to create the perfect environment for high yeast quality and yield.
Measures include a controlled addition of molasses, balanced oxygen and nutrition supply, efficient temperature control and an easy-to-clean plant design.
In order to optimize the long-term cost-benefit ratio of the plant, we pay close attention to process economics, with low energy and utility consumption, and high yields, taking into account customer-specific requirements such as the local availability of water.
Vogelbusch equipment that can greatly enhance process efficiency includes:
The most suitable aeration system is chosen based on fermentor size, production capacity and available utilities. Three types of tried and tested industrial aeration systems are available for specialized applications.
More about » Aeration systems
Sensor-equipped analyzers continuously measure the alcohol concentration in the fermenting mash. Gas phase measurement using semiconductor sensors is normally recommended for baker's yeast, but liquid-phase measurement with custom retractable probes is also available.
More about » Gas analyzers
Vogelbusch provides highly specialized services for yeast production plants including
Our experts are also available for consultancy services such as strain supply and optimization, and laboratory and pilot plant testing.
Figures vary considerably depending on raw material, plant capacity and configuration as well as local conditions. To determine specific consumption figures, operating cost and investment cost, a feasibility study can be carried out for your particular case.
Fermentable monosaccharide per 1,000 kg yeast
| Wet (30 % DS) | ||
| Sugar consumption | kg | 625 |
Fermentable monosaccharide per 1,000 kg yeast
| iADY 96 % DS | ||
| Sugar consumption | kg | 2,250 |
No. Yeast is manufactured in a fairly complex processing facility consisting of a range of process units.
No. Only molasses from a sugar FACTORY can be used as it contains not only sugar but also specific substances which are required as nutrient for yeast propagation.
Molasses from a sugar REFINERY (= for conversion of raw sugar into white sugar) can not be used.
It would be technically possible but is uneconomic in operation.
Yeast plants can be operated 24 hours per day, year round. Cycles of five or six days per week are also possible.
Technically speaking, a small yeast plant could have a capacity of only 1,000 kg fresh yeast per day. Economically though, this can be recommended only under certain conditions, for instance for own requirements in a bakery.
To remain competitive in trade, the lower limit for an economically feasible production is in the range of 10 to 20 tons per day (wet).
Capital expenditure strongly depends on plant capacity and configuration as well as local conditions. Costs for the complete process plant (excluding land, buildings, waste water treatment and infrastructure) are from euro 5 million upwards. This figure is for general reference only since each project has its own particularities that need consideration.
Large quantities of drinking water are required in production and subsequently, large volumes of waste water are produced that need treatment.
The plant site therefore has to have a reliable source of potable water and a waste water treatment facility has to be foreseen.
For a small sized factory an area of 100 x 75 m is necessary.
With permits on hand engineering and construction takes 18 - 24 months.
Complete our design questionnaire (check Links & Downloads section below) and send it back to us to get a professional opinion on your project.
