this presentation elaborates about the process of producing baker's yeast in detail contents:1)Introduction 2)media and other raw material preparation 3)fermentation conditions 4)industrial preparation 5)Flowchart for the production of baker’s yeast 6)applications of bakers yeast.

1. Production of baker’s yeast

2. Introduction
• Baker's yeast is the common name for the strains of
yeast commonly used in baking bread and other
bakery products, serving as a leavening agent which
causes the bread to rise by converting the fermentable
sugars in the dough into carbon dioxide and ethanol.
• In early ages, inoculum from fermentation was used
for bread making but it’s not practical because yeast
grow very slowly
• Hence forth, it is essential for present day baking
industries to have large scale commercial yeast
available.

3. Culture
-Special strain of Saccharomyces cerevisiae is used
Carbon source
-commonly used is cane or beet molasses
Nitrogen source
-The most common ammonia salts, urea and liquid NH3
Trace elements
-Fe, Zn, Cu, Mn and Mo are required
Vitamins and bios factors
-Biotin, pantothenic acid are required in concentration of 0.29 ppm,50 ppm and 1200 ppm
Media & other raw material
preparation

4. FERMENATION CONDITIONS
TEMPERATURE:28-30C,therefore efficient cooling system is required
PH: 4.5-5 it is adjusted by adding phosphoric acid
COOLING SYSTEM: Large amount of heat is produced during aerobic respiration, thus
to maintain the optimum temperature cooling system is required.
AERATION AND AGITATION SYSTEM: It is very essential as vegetative growth of yeast
is favorable under aerobic condition at low concentrations of sugar and high aeration

5. Industrial production
INOCULUM DEVELOPMENT
• The desired strain is maintained in a frozen state
• The inoculum is prepared in stage so that large volumes are
finally obtained
• From the inoculation reactor(fermenter),the culture is
transferred to production reactors.
ADDITION OF SUGARS
• The process is carried out in air-lift or bubble column type
reactor
• Production is mainly done by fed batch fermentation and
carried out by incremental feeding of the substance to
prevent glucose effect

6. • Intermittent addition is done to maintain sugar
concentration at a low level so that can favor respiration
not fermentation.
• After 12-18hrs,the yeasts are washed, centrifuged and then
dewatered on a production drum
• The fresh yeast obtained can be directly used or stored.
STORAGE
• The yeast cells obtained can be mixed with plasticizer(e.g.
vegetable oil) and prepared in a block form
• This block can be cut into small pieces,
cut into small pieces, wrapped and stored
(at 4C) until used

7. Flowchart for the production of baker’s
yeast

8. Flowchart for the production of baker’s yeast

9. Applications
• The principle use of Baker's yeast is as an essential bakery
ingredient- for causing fermentation in the dough used in
making bakery items. This process helps making soft and
fluffy bakery items like variety of breads, bread rolls, pizza
base, cracker biscuits, sweet breads and burger buns etc.
• Because it is readily available and easy to culture, baker's
yeast has long been used in chemical, biological, and
genetic research as a model organism.
• Baker's yeast can also be used to produce ethanol via
fermentation for use in chemical synthesis, although doing
so in some places requires permits.

10. Presentation by Samyuktha Magesh
B.Tech-biotech 3rd year