Knowledge Centre

Yeast Production

Anchor Yeast has a modern manufacturing facility in Durban, which had its origins as a second generation industrial bio-technology plant producing lysine. It was acquired by Lallemand in 2009.

Process description

  • The first stage of yeast production starts with a small sample of pure yeast inoculum in the laboratory. The strain used for baker’s yeast production is Saccharomyces cerevisiae. The pure inoculum is aseptically transferred to fermenter vessels of incremental size. Each fermentation growth stage is typically completed in 16 to 24 hours, after which 20 000 to 30 000 kg of fresh yeast is produced. The yeast is harvested from the final fermentation stage by large centrifugal separators, which separate the spent wort from the heavier yeast cells. The resulting yeast cream is transferred to storage tanks at low temperature, where it is standardized as cream yeast, or processed further as compressed or dry yeast. Yeast cream for compressed yeast is dewatered further on a rotary vacuum filter, extruded into blocks, wrapped, boxed and stored in a cold room ready for dispatch. The dewatering stage for dry yeast manufacture occurs via large membrane filter presses. The resulting yeast cake is extruded in fine strands and dried in fluid bed dryers. Bulk dry yeast silos are used for storing the yeast before packing off as industrial or consumer products.

Raw materials

  • The key raw materials used in producing baker’s yeast are the pure yeast culture and molasses. Cane molasses contains 45 to 50 percent fermentable sugars, in the form of sucrose, glucose, and fructose. The molasses mixture is diluted, clarified to remove any sludge, and then sterilized with high-pressure steam. After sterilization, it is held in holding tanks until it is needed for the fermentation process.


  • The yeast industry has progressively evolved into a high-tech industry, which through the years has benefited from scientific advances in the field of bio-technology. This technology has ensured that the various yeast strains meet the needs of local and international yeast users, ranging from baking and brewing to wine, whisky and bio-control industries.
  • Anchor Yeast’s philosophy of investment in technology and research and development has resulted in highly automated and computer-controlled manufacturing and packing facilities. This enables flexible manufacturing of both high volume and speciality yeast products.
  • The company’s success as leaders in yeast technology in South Africa and Sub-Saharan Africa, is further attributed to stringent quality control measures, certified management systems and adherence to food safety standards.