Yeast Breads
Ingredients
Yeast - Saccharomyces cerevisiae, cells
metabolize sugar (fructose, glucose,
sucrose, maltose) and release CO2.
C6H12O6 --> 2 C2H5OH + 2 CO2
glucose
ethyl alcohol carbon
dioxide
Yeast also effects elasticity, stickiness,
and flow properties.
Flour - high protein content for good
gluten development.
Liquid - dissolution, hydration, and
gelatinization.
Salt - flavor, also favors amylase action
and inhibits protein splitting enzymes.
Sugar - fermentable sugar for yeast.
Problems
Excess flour - stiff inelastic dough, slow to
rise, limited expansion in baking, cells
small, thick walls, small volume.
Excess sugar - above 10% sugar inhibits
yeast, delays water uptake by flour.
Yeast - 1/3 to 1 1/3 packages per 1 1/2
cups flour. Too little increases rising time.
Too much causes inflation prior to other
changes. Gives yeasty flavor.
Basic Methods of Making
Yeast Bread
Straight dough - liquid warmed with sugar,
salt and fat. Cooled, yeast is added to
mixture. Flour added, beaten, more flour,
kneaded, then raised.
Batter or No Knead - more liquid, gluten
develops in bowl as batter is beaten.
Sponge - liquid, sugar, yeast, and part of the
flour are mixed. Allowed to become light
and fluffy in bowl, remainder of flour, fat, and
salt are added. Kneaded and raised.
Principles
Kneading - allows development of strong
elastic gluten.
Fermentation - period where dough is
allowed to rise in bowl and yeast produces
leavening gas.
Punching - light kneading after fermentation
prior to shaping.
Proofing - final rising in the pan after dough
is shaped.
Ovenspring - rapid increase in loaf volume
when first put into the over for baking.
Other Yeast Products
Rolls-Kaiser, submarine, hot dog,
hamburger, etc
Pita bread
Bagels
English muffins
Pizza crust
Pretzels/Bread Sticks
Raised doughnuts
Choice of Breadstuffs
Select whole grain or enriched, avoid
sweet and rich items. Choice influenced
by family preference, convenience and
time savings and cost.
Ready-to-serve
Bake and eat
Package mixes
Bread Staling
Crust becomes tough and leathery
Crumb is dry, harsh and crumbly
Theorized due to aggregation of amylose
molecules, recrystallization of amylopectin
molecules sometimes called
retrogradation, or the transfer of moisture
from gluten to the starch.
Delay by: covering and storing at 60 C or
140 F or freezing