This document discusses different methods of aeration used in baking. It describes physical aeration through whisking or beating ingredients like eggs. Biological aeration uses yeast, a living microorganism, to ferment sugars into carbon dioxide gas. Chemical leaveners like baking powder are also discussed, which release gas through chemical reactions with moisture and heat. Too much of a raising agent can cause over-aeration and result in a collapsed or heavy final product.

1. Aeration

2. Introduction to aeration
• It’s a process of incorporating air in the
mixture
• Aeration happens due to following ways
Beating Whisking

3. Intro….
• Raising agents are also used for aeration
which creates gas bubbles puffing up &
eventually increase the volume of the product
and provides required spongy structure after
the baking usually done
for dough and batters that cause a foaming
action which lightens and softens the finished
product.

4. Intro….
• Use of too much raising agent raise the food
too rapidly and breaks the surface area and
allows the gas produced to escape, and as a
result, the dough sinks and become heavy.

5. Types of Raising Agents
–Physical raising agent
–Biological raising agent
–Chemical raising agent

6. Physical Raising Agent
In this method gas is incorporated by
whisking or beating the egg or
emulsifier. Egg and emulsifier has got
ability to incorporate gas or liquid as a
result of which volume raises.
E.g whisking cake , hollandaise sauce.

7. Biological Raising Agent
Biological raising agents are the raising agent where
living micro organism are activated for its reaction
Yeast is the living micro organism which is available
dry as well as fresh. It is pale grey in color. The
main function of yeast is to convert sugar into
carbon dioxide. Yeast needs moisture, sugar,
warmth and air for its action.
Raising with yeast is a process based on fermentation,
biologically which usually activates as soon as the
water combines the acid and base chemicals &
requires proofing, which allows the yeast time to
reproduce and consume carbohydrates in the flour.

8. Varities of biological raising agent
• Yeast
• Beer
• Buttermilk
• Sourdough starter
• Yogurt

9. Chemical Raising Agent
Chemical leaveners are chemical mixtures or
compounds that release gases (usually carbon
dioxide) when they react with moisture and heat
Chemical leaveners are used in quick cakes, as well as
cookies and numerous other applications where a
long biological fermentation is impractical or
undesirable to taste and texture.

10. Varieties of chemical Raising Agent
• Baking powder
• Baking soda (sodium bicarbonate)
• Mono calcium phosphate
• Sodium aluminum phosphate (SALP)
• Sodium acid pyrophosphate (SAPP)
• Potassium bi-tartrate (cream of tartar)