2. Yeasts
what is bakers yeast?
(Saccharomyces cerevisiae) living organism used in bread baking -One-celled fungus multiplies rapidly at right temperature & presence of a small amount of sugar & moisture
function of salt
- gives the yeast bread flavor. -also added to inhibit yeast growth; otherwise, they would continue to multiply and produce too much carbon dioxide that would cause the bread to rise too much and possibly collapse.
how does milk affect bread
- makes dough rise more quickly because the yeast thrives on lactose This natural sugar also aids in browning the baked bread. - also adds flavor and nutrients, and, like fat, helps keep bread fresher longer.
over proofing
-Over-expansion of dough = over-extension of gluten -Cell walls break and collapse -Fermentation gas escapes, resulting in Low volume -Doughs that are too cool ferment too slowly; too hot = too quickly
how do you test for doneness in bread
-Rings hollow when tapping bottom of freshly cooked loaf -Rings hollow + internal temperature >195ºF (91ºC) -Microwave preparation - Not recommended - absence of dry heating required for dextrinization, Maillard reaction or caramelization
what are the two types of yeast?
-active dry yeast -compressed, fresh yeast
function of liquid in yeast breads?
-dissolves and activates the yeast and moistens the flour so the gluten can develop. -Temperature of this has to be just right for yeast to grow ((120°F/49°C to 130°F/54°C) if other ingredients added to yeast
Function of fat in yeast breads?
-impacts taste and color of baked bread. -it also retard gluten development, so the bread will have a softer smoother texture. -slows down moisture loss, so they stay fresher.
crumb development
...
how long does it take to bake a standard loaf of bread? and at what temp.
45 minutes at 400F for the first 10-15 mins then 350 for the remaining 30 mins
optimal fermentation temperature
68-100F Slow down < 50°F (10°C) Killed if exposed to ≥ 140°F (60°C)
how to prevent staling
Add mono- and diglycerides or fat
Before it is baked, bagel dough undergoes what cooking process?
Boiling
baking
Changes appearance, texture, flavor, aroma Yeast killed Protein coagulates Starch swells & gelatinizes Fat melts Odor of baked crust - formation of a furanone compound resulting from the Maillard reaction and presence of organic acids
sugar and other sweetener functions
Food for the yeast, makes the dough rise. -also helps bring out other flavors -also caramelizes and gives a nice brown crust
what happens if initial temperature is not hot enough?
If initial temperature is not hot enough, protein will not coagulate properly, fermentation continues, and dough spills over edge
High-altitude adjustment (>3,000 feet)
Less leavening - less atmospheric pressure More liquid - since it evaporates quicker Breads rise faster increased oven temperature- help coagulate protein and prevent over expanding gases
Rapid mix
Mixes in bread makers, and kneads it and then bakes it in the same pan.
some problems with texture with fermentation
Overfermentation - mouth-eaten appearance & coarse texture Underfermentation - dense loaf, thick cells, low volume, tough crust
Straight dough
Placing all ingredients in bowl at the same time
Batter method
Simplest; combine ingredients; beat via hand or electric blender, no kneading
cultured whey
a natural mold inhibitor similar to calcium proppionate
oats function
adds texture and nutty flavor
why do we punch down dough
allows excess gas to escape and redistributes the ingredients.
The method of mixing ingredients and beating them together by hand or a mixer without kneading is known as the______method.
batter
Scoring a bread refers to:
cutting across the top to prevent the crust from tearing.
active dry yeast
dehydrated and can be purchased in 1/4 packets, takes 1/3 to 1/2 the time of regular yeast
how to test if the dough is finished rising
double in size and finger indention test
eggs
enrich the taste, texture, and color of some yeast breads, adding strength to the elastic network formed by the gluten. They are most typically used in sweet yeast bread recipes.
Whole-wheat bread is a great source of , whereas white bread is a poor source.
fiber
When baking at altitudes above 3,000 feet, liquids need to be-------- and temperatures need to be------
increased, increased
compressed fresh yeast
moist and perishable, in the refrigerated isle 1/4 ounce package yeast = 1 scant tablespoon dry yeast
calcium propionate
mold inhibitor that has no effect on PH, so it is preferred.
what to look for in a well prepared bread
optimal volume, color, and flavor, a symmetrical shape with closed seams; even crumb, pliable, golden brown crispy crust
What is the term used to describe the quick expansion of dough caused by expanding gases during the first 10 minutes of baking?
oven spring
oven spring
quick expansion of dough during the first 10 minutes of baking, caused by expanding gases.
what does kneading do?
realigns protein molecules
how do you check if dough has been sufficiently kneaded?
stretch and see if the thin translucent windowpane appears
Numerous small/medium cells =
tender crumb, large volume, and longer shelf life
proof
to increase the volume of the shaped dough through continued fermentation -helps maintain humidity and prevent drying out -Increases volume of shaped dough through continued fermentation Creates adequate aeration of dough
why are Sodium or calcium propionate added
to retard mold & bacteria growth that cause rope (smell of overripe melons)
monocalcium phosphate
used as a yeast nutrient, dough conditioner, and acid producer. Lowering the ph of the production inhibits mold growth
what is the function of flour in yeast breads?
wheat is most commonly used because it is the flour with highest amount of gluten. -gluten provides firm, elastic structure.
Breads leavened with carbon dioxide produced by baker's yeast are known as
yeast breads
how does leavening occur ?
yeast is mixed with liquid and some type of sugar and kept at proper temperature to ferment. -co2 and alcohol produced, alcohol burns off during baking and co2 is trapped, and it expands the gluten so the bread rises.
what contributes to the cell number and side in yeast breads?
yeast, and air incorporated into the flour mixture during mixing punching, and kneading. this is why using sifted flour gives products with larger volumes.
Kneading
~ 10 Minutes Develop gluten Physically handling dough Smooth, soft, non-sticky surface Not needed w/ batter method
Sponge
Combine yeast, water, & 1/3 of flour; allow to ferment in warm place; add remaining ingredients
Staling
Crust toughens, crumb becomes less elastic/more firm, loss of moisture & flavor
Changes during fermentation
Dough doubles, becomes more acidic -- pH 6.0 - 5.5-5.0 - formation of carbonic acid, lactic and acetic acids Alcohol - produced as well - evaporates during baking Avoid over-fermentation or dough will collapse
