Acetic Acid
An organic acid produced during fermentation that contributes a sharp, tangy quality to sourdough flavor.
Sourdough Dictionary: A–Z Sourdough Baking Terms | Squirrelly Girl
The Sourdough Dictionary
Everything sourdough, all in one place. From sourdough starter and wild yeast to fermentation, flour, gluten, shaping, scoring, baking and troubleshooting, this is your growing A–Z reference to the language of sourdough baking.
A Living Dictionary for Sourdough Bakers
Sourdough has its own language. This dictionary explains the terms, ingredients, techniques, science, equipment and troubleshooting concepts you are most likely to encounter when working with a sourdough starter and baking naturally fermented bread. We will continue expanding this resource as we explore more of the wonderfully obsessive world of sourdough.
A
Sourdough Terms Beginning With A
Acidification
The process by which fermentation lowers dough or starter pH as organic acids are produced.
Acid Tolerance
The ability of sourdough microorganisms to remain active as the starter environment becomes increasingly acidic.
Active Starter
A sourdough starter that is actively fermenting, producing bubbles and rising after feeding.
Alveoli
The small pockets of gas within bread crumb created primarily by fermentation and dough structure.
Amylase
An enzyme that breaks starches into smaller sugars that can be used during fermentation and baking.
Amylolysis
The enzymatic breakdown of starch into simpler carbohydrates.
Artisan Bread
A broad term commonly used for traditionally made breads emphasizing fermentation, flavor, texture and craftsmanship.
Autolyse
A period of rest after flour and water are combined, allowing hydration and beginning gluten development before the final dough is mixed.
B
Sourdough Terms Beginning With B
Baker's Percentage
A method of expressing ingredient quantities as percentages of the total flour weight.
Banneton
A proofing basket used to support shaped dough during its final rise.
Batard
An elongated oval-shaped loaf commonly used for sourdough bread.
Bench Rest
A period during which dough rests after dividing or preshaping before final shaping.
Biga
A relatively stiff Italian-style preferment used in bread baking.
Boule
A round, ball-shaped loaf of bread.
Bran
The outer layer of a grain kernel, rich in fiber, minerals and other components.
Bread Flour
Flour with relatively high protein content that generally develops strong gluten suitable for bread.
Bulk Fermentation
The main fermentation period after mixing the dough and before dividing and shaping it.
Bubbles
Pockets of carbon dioxide produced by fermentation that provide visible evidence of microbial activity.
C
Sourdough Terms Beginning With C
Carbon Dioxide
A gas produced by yeast fermentation that becomes trapped in dough and contributes to rising.
Chlorine
A disinfectant sometimes present in municipal water that can potentially affect sensitive fermentation cultures.
Coil Fold
A gentle dough-strengthening technique in which the dough is lifted and folded underneath itself.
Cold Fermentation
Fermentation carried out at refrigerator temperatures, slowing microbial activity and extending fermentation time.
Cold Proof
A final proof performed in the refrigerator before baking.
Crumb
The interior structure and texture of a loaf of bread.
Crumb Structure
The size, distribution and shape of the air pockets throughout baked bread.
Crust
The browned exterior layer of bread formed during baking.
Culture
The living community of yeasts and bacteria maintained in a sourdough starter.
D
Sourdough Terms Beginning With D
Degassing
The deliberate removal of some accumulated fermentation gas from dough.
Discard
Starter removed during feeding or maintenance before fresh flour and water are added.
Discard Recipes
Recipes designed to use excess sourdough starter rather than throwing it away.
Dough Development
The process of developing sufficient strength and structure in dough for fermentation and baking.
Dough Hydration
The percentage of water relative to flour in a dough formula.
Dough Temperature
The temperature of dough during fermentation, which strongly influences fermentation speed.
Dough Strength
The ability of dough to retain its shape and fermentation gases.
Dough Whisk
A tool designed to mix flour, water and other dough ingredients.
Dutch Oven
A heavy covered baking vessel commonly used to trap steam around sourdough during oven spring.
E
Sourdough Terms Beginning With E
Elasticity
The tendency of dough to return toward its original shape after being stretched.
Enriched Dough
Dough containing ingredients such as butter, eggs, milk or sugar in addition to the basic flour, water, salt and leavening system.
Enzyme Activity
The activity of naturally occurring enzymes that influence starches, proteins and other components of dough.
Extensibility
The ability of dough to stretch without tearing.
F
Sourdough Terms Beginning With F
Fermentation
The biological process through which microorganisms metabolize available food sources and produce compounds including acids and carbon dioxide.
Fermentolyse
A dough-mixing approach in which flour, water and sourdough starter are combined and rested before salt is added.
Fermentation Temperature
The temperature at which dough or starter ferments and one of the major factors affecting fermentation speed.
Final Proof
The final fermentation period after shaping and before the dough is baked.
First Rise
A common name for bulk fermentation.
Flour
Ground grain or other plant material used as the primary structural ingredient in bread.
Flour Protein
The protein content of flour, which strongly influences gluten development and dough strength.
G
Sourdough Terms Beginning With G
Gluten
A protein network formed when certain wheat proteins interact with water and mechanical mixing.
Gluten Development
The process of building the dough's protein network so it can stretch and retain fermentation gases.
Glutenin
One of the primary wheat proteins contributing elasticity and strength to gluten.
Gliadin
A wheat protein associated with the extensibility of gluten.
Grigne
The raised, opened edge created when a scored loaf expands during baking.
H
Sourdough Terms Beginning With H
Hooch
A layer of liquid that can form on a neglected or very hungry sourdough starter.
Hydration
The amount of water in relation to flour, normally expressed as a baker's percentage.
Hydration Percentage
The percentage obtained by dividing water weight by flour weight and multiplying by 100.
High-Hydration Dough
A dough containing a relatively high proportion of water compared with its flour.
I
Sourdough Terms Beginning With I
Inactive Starter
A starter that is not currently showing significant fermentation activity.
Inoculation
The amount of mature starter or preferment introduced into a dough or new fermentation mixture.
Inoculation Percentage
A measurement describing the amount of starter or preferment relative to the flour in a formula.
Internal Temperature
The temperature measured inside baked bread, often used as one indicator of doneness.
J
Sourdough Terms Beginning With J
Jelly Crumb
A descriptive term sometimes used for a translucent or unusually moist bread interior.
K
Sourdough Terms Beginning With K
Kahm Yeast
A thin surface yeast growth that can sometimes appear on fermented foods. It is distinct from the desirable sourdough culture.
Kneading
A mechanical dough-development technique used to develop strength and distribute ingredients.
L
Sourdough Terms Beginning With L
Lactic Acid
An organic acid produced by lactic acid bacteria and an important contributor to sourdough flavor and acidity.
Lactic Acid Bacteria
A group of microorganisms important to sourdough fermentation and acid production.
Lame
A specialized bread-scoring tool used to make controlled cuts in dough.
Levain
A preferment made from sourdough starter, flour and water that is prepared for use in a bread dough.
Liquid Starter
A sourdough culture maintained with a relatively high proportion of water.
Long Fermentation
A fermentation schedule that allows dough to develop over an extended period.
M
Sourdough Terms Beginning With M
Maillard Reaction
A group of chemical reactions between amino acids and reducing sugars that contribute to the color, aroma and flavor of baked bread.
Mature Starter
A well-established sourdough culture capable of reliably fermenting dough.
Miche
A traditional term commonly associated with a large, rustic French-style country loaf.
Mother Starter
The ongoing sourdough culture maintained from one feeding to the next and used to create levains or dough.
Mixing
The process of combining flour, water, starter, salt and other ingredients to create dough.
N
Sourdough Terms Beginning With N
Natural Leavening
Leavening produced through naturally occurring microorganisms rather than commercial baker's yeast.
Natural Yeast
A common informal term for the wild yeasts present in a sourdough culture.
Nominal Hydration
A descriptive way of referring to the stated water-to-flour ratio of a starter or dough.
O
Sourdough Terms Beginning With O
Oven Spring
The rapid expansion of dough during the early stages of baking.
Open Crumb
A bread interior containing relatively large and irregularly distributed air pockets.
Over-Fermentation
A condition in which dough ferments beyond its optimal point, potentially losing strength and structure.
P
Sourdough Terms Beginning With P
Pan Loaf
Bread baked inside a loaf pan rather than free-form on a baking surface.
Pain au Levain
French terminology for bread leavened with sourdough culture.
Pâte Fermentée
A piece of previously fermented dough used as a preferment in a subsequent dough.
Peak Activity
The period when a starter has reached its highest visible fermentation activity after feeding.
Peak Starter
A starter at or near its maximum rise and fermentation activity.
Preferment
A portion of dough ingredients that is fermented in advance before being incorporated into the final dough.
Preshaping
An initial shaping step that organizes dough before the final shaping.
Proofing
A period of fermentation after shaping and before baking.
Protein Content
The percentage of protein in flour, an important factor affecting gluten development and dough characteristics.
Q
Sourdough Terms Beginning With Q
Quell
An uncommon descriptive baking term referring to reducing or suppressing activity; not a standard sourdough technical term.
Quick Fermentation
A fermentation schedule using favorable temperatures or higher inoculation to shorten fermentation time.
R
Sourdough Terms Beginning With R
Refresh
To feed a sourdough starter with fresh flour and water.
Refreshment
Another term for feeding a sourdough culture.
Retardation
The deliberate slowing of fermentation, commonly by refrigerating dough.
Ripe Starter
A starter that has developed sufficient fermentation activity and is ready to use.
Rising
The visible increase in dough or starter volume caused primarily by fermentation gases.
Rubaud Method
A dough-mixing technique using repeated scooping and folding motions to develop dough strength.
S
Sourdough Terms Beginning With S
Scoring
Cutting the surface of dough before baking to control expansion and create decorative patterns.
Second Rise
A common informal term for the final proof after shaping.
Slap and Fold
A hands-on technique in which dough is repeatedly lifted, slapped against the work surface and folded.
Sourdough
Bread or other baked goods leavened through a culture containing naturally occurring yeasts and bacteria.
Sourdough Discard
The portion of starter removed during feeding or maintenance.
Sourdough Starter
A living culture of flour, water, wild yeasts and bacteria maintained through regular feeding.
Starter Feeding
The addition of fresh flour and water to maintain and strengthen a sourdough culture.
Starter Ratio
The proportion of starter, flour and water used during a feeding.
Starter Strength
The ability of a sourdough culture to ferment dough effectively and predictably.
Stretch and Fold
A gentle dough-strengthening technique involving stretching one portion of dough and folding it over itself.
Stiff Starter
A sourdough starter maintained with less water relative to flour, producing a thicker consistency.
Steam
Moisture in the oven during the early stages of baking that helps delay crust formation and supports oven spring.
Starch Gelatinization
The transformation of starch granules during heating in the presence of water, contributing to bread crumb formation.
T
Sourdough Terms Beginning With T
Temperature
One of the most important variables affecting sourdough fermentation speed and timing.
Thermometer
A tool used to measure dough, starter, oven or bread temperature.
Tartine
A term associated with open-faced sandwiches and, in modern sourdough culture, a style of naturally leavened artisan bread.
Total Flour Weight
The total flour quantity used as the reference point when calculating baker's percentages.
U
Sourdough Terms Beginning With U
Under-Fermentation
A condition in which dough has not fermented sufficiently before baking.
Unbleached Flour
Flour that has not been chemically bleached after milling.
Unfed Starter
A starter that has not recently received fresh flour and water.
V
Sourdough Terms Beginning With V
Volume
The amount of space occupied by a dough or starter, often monitored to judge fermentation progress.
Vital Wheat Gluten
A concentrated wheat protein product sometimes added to dough to increase gluten strength.
W
Sourdough Terms Beginning With W
Water Absorption
The amount of water flour can absorb while maintaining a particular dough consistency.
Weak Starter
A sourdough culture that does not ferment strongly or predictably after feeding.
Wild Yeast
Yeasts naturally present in the environment and flour that participate in sourdough fermentation.
Whole Grain
Grain containing the bran, germ and endosperm.
Whole Wheat Flour
Flour containing all major components of the wheat kernel.
X
Sourdough Terms Beginning With X
Xylanase
An enzyme that acts on components of plant cell walls and can influence dough properties and bread quality.
Xylose
A simple sugar found in plant materials that can participate in complex reactions during baking.
Y
Sourdough Terms Beginning With Y
Yeast
A microorganism responsible for fermenting sugars and producing carbon dioxide and other fermentation byproducts.
Yeast Activity
The rate and level at which yeast populations ferment available sugars.
Yeast Fermentation
The metabolic process through which yeast converts available sugars into products including carbon dioxide and alcohol.
Z
Sourdough Terms Beginning With Z
Zero Waste Starter
An approach to sourdough maintenance that minimizes discarded starter by planning feedings and using excess culture in recipes.
Zymase
A group of enzymes associated with yeast fermentation and the conversion of sugars into fermentation products.
Keep Exploring Sourdough
The dictionary is only the beginning. Explore more of the Squirrelly Girl sourdough library for practical guides, techniques, recipes and starter resources.
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