Words, Phrases, and Concepts Glutenin Gliadin Tenacity Elasticity Extensibility Windowpane Bucky dough Slack dough Mechanical dough development Chemical dough development Water hardness pH Letdown stage Reducing agent Glutathione Protease Dough relaxation
Introduction Gluten: –One of three main structure builders in baked goods. Egg proteins and starch are other two. Especially important with yeast doughs. –Affected by formula and method of preparation.
Gluten Formation and Development Gluten: –Is a large, complex protein. Made up of glutenin and gliadin, two proteins in flour. –Forms a strong, stretchy network when flour is mixed with water. Glutenin: provides strength and elasticity. –Strength is also called tenacity; a measure of how much force is needed to stretch dough. –Elasticity refers to the ability to bounce back once dough is stretched. Gliadin: provides extensibility, or stretchiness.
Gluten Formation and Development Yeast doughs need a balance of glutenin and gliadin: –Need a balance of strength and stretchiness.
Gluten Formation and Development Gluten: –Changes as it is handled. –Dough becomes smoother, stronger, drier, and less lumpy as gluten develops.
Gluten Formation and Development When yeast dough reaches a balance of strength and stretchiness: –Has reached dough maturity. –Can be stretched into a paper-thin sheet of dough known as a windowpane.
Determining Gluten Requirements Baked goods vary in their need for gluten. Yeast doughs need gluten for fermentation tolerance: –For the ability of dough to hold in gases generated from yeast fermentation. –Important throughout proofing and oven spring. Provides for large loaf volume and fine crumb. Ciabatta dough requires less gluten than sandwich bread (pain de mie).
Measuring Gluten Alveograph Measures elasticity- P Measures extensibility- L P/L W- Energy required to inflate dough
Determining Gluten Requirements Baked goods vary in their need for gluten. Cakes and most other pastries need less gluten than yeast doughs. –Many rely more on other structure builders (eggs and starch). –However, gluten often needed to prevent crumbling, collapsing, or slumping. Examples: pie crust, baking powder biscuits.
Controlling Gluten Development Three ways that gluten develops and matures in yeast dough: –Mechanical dough development: mixing. –Chemical dough development: addition of maturing agents that strengthen. –Bulk fermentation and proofing. Complex; many changes besides gluten development occur simultaneously. Each acts differently, but all encourage gluten development.
Gluten Formation and Development Gluten development : Results from the alignment and bonding of glutenin into a large, cohesive gluten network.
Controlling Gluten Development Many ways to control gluten development: –Know how to increase gluten so that: Dough is stronger and more elastic, or Baked good is firmer and holds it shape. –Know how to decrease gluten so that: Dough is softer, slacker, and more extensible, or Baked good is more tender. Not all techniques work in all products: Examples: dough conditioners, heat-treated milk.
Controlling Gluten Development 1.Type of flour –Type of grain. Wheat, rye, oat, corn, etc. –Wheat is only grain with significant glutenin and gliadin. –Varieties of wheat. Soft, hard, durum. –White vs. whole wheat.
Controlling Gluten Development 2.Amount of water –When gluten is not fully hydrated, additional water increases gluten development. Examples: pie and biscuit doughs. –When gluten is fully hydrated, additional water dilutes and decreases gluten development. Examples: cake batter, well-hydrated bread dough.
Controlling Gluten Development 3.Water hardness –Measure of mineral content: calcium and magnesium. Hard water is high in minerals; produces strong, bucky dough. Soft water is low in minerals; produces soft, slack extensible dough. –In yeast doughs, usually best to have water that is neither too hard nor too soft, so that strength and extensibility are in balance.
Controlling Gluten Development Water hardness varies across the country.
Controlling Gluten Development 4.Water pH –Measure of acidity or alkalinity. –For maximum gluten: pH = 5-6 (slightly acidic). –Adding acid lowers pH. Example: Vinegar makes strudel dough softer, more extensible. –Adding alkali (base) raises pH. Example: Baking soda makes cookies thinner, more open, more tender.
Controlling Gluten Development 5.Mixing and kneading –The more mixing, the more gluten development – up to a point. –Mixing increases gluten development as it: Speeds up hydration of flour particles. Adds oxygen from air into dough. Distributes particles evenly throughout dough.
Controlling Gluten Development 5.Mixing and kneading (cont.) –Lengthy or vigorous mixing breaks down gluten structure. Letdown stage of mixing yeast doughs. Dough becomes soft, sticky, easily torn. The weaker the gluten, the more easily it overmixes. Examples: rye dough; rich, sweet yeast doughs.
Controlling Gluten Development 6.Batter/dough temperature –Warmer the temperature, the faster gluten develops. Not a common means of controlling gluten development. Examples: yeast-raised dough; pie pastry dough
Controlling Gluten Development 7.Maturing agents and dough conditioners –Maturing agent that weakens gluten: chlorine. –Maturing agent that strengthens: ascorbic acid. –Dough conditioners: Multifunctional ingredients. Primarily, they strengthen gluten.
Controlling Gluten Development 8.Fermentation and proofing –Expanding air bubbles push on gluten, strengthening it. –Additional fermentation and proofing can weaken gluten. Dough becomes softer and more extensible. –Overall, complex effect on gluten: many chemical and physical changes happening.
Controlling Gluten Development 9.Reducing agents –Opposite of maturing agents that strengthen. –Weaken gluten; doughs become softer, more extensible. –Example: glutathione Found in: fluid milk, active dry yeast, wheat germ.
Controlling Gluten Development 10.Enzyme activity –Proteases are enzymes that break down proteins, including gluten. –Weakens gluten; dough becomes softer, more extensible.
Controlling Gluten Development 10.Enzyme activity (cont’)
Controlling Gluten Development 11.Tenderizers and softeners –Interfere with or limit gluten development. –Examples: Fats, oils, and emulsifiers. –Shortening is named for the ability of fats to “shorten” gluten strands. Sugars. Leavening gases. –Gluten strands stretch thin as leavening gases expand, weakening cell walls.
Controlling Gluten Development 12.Salt –Strengthens gluten and makes it less sticky. Prevents excessive tearing as gluten stretches. Salt is sometimes added late in the mixing of yeast doughs. –Reduces frictional heat from mixing.
Controlling Gluten Development 13.Other structure builders –Interfere with gluten development, even as they contribute their own structure. Example: starches, especially if ungelatinized; eggs in rich sweet yeast doughs.
Controlling Gluten Development 14.Milk –Fluid milk: Source of water; increases gluten development. Contains glutathione; reduces gluten during fermentation and proofing. –Dough becomes softer, more extensible. –Scalding milk first inactivates glutathione. –Dry milk solids (DMS): Low-heat DMS: contains glutathione; weakens gluten. High-heat DMA: contains no glutathione; does not weaken gluten.
Controlling Gluten Development 15.Fiber, bran, grain particles, fruit pieces, spices, etc. –Weaken gluten by shortening gluten strands. Particles physically interfere with gluten strands from forming.
Controlling Gluten Development Dough relaxation –Dough resting period. Bench rest for yeast doughs. Refrigeration of laminated doughs between folds. –Refrigeration also solidifies fat, for more flakiness. –Makes it easier to shape, roll and fold dough properly. Dough is less elastic and more extensible. –Dough shrinks less during baking.
Sweeteners Many sweeteners available. –Dry sugars. –Syrups. –Specialty sweeteners. Sweeteners vary in sweetness and other functions. Successful bakers and pastry chefs: –Know the features of each sweetener. –Know how to substitute one for another.
Sweeteners Sugars –“Sugar” refers to regular granulated sugar; sucrose. –Other sugars: fructose, glucose, maltose, lactose. Available as dry sugars but typically purchased in syrup form. –All sugars are carbohydrates. Molecules made up of carbon (C), hydrogen (H), and oxygen (O) atoms.
Sweeteners Sugars –Some sugars are monosaccharides. Contain one (mono) sugar unit (saccharide).
Sweeteners Sugars –Other sugars are disaccharides. Contain two (di) sugar units bonded together.
Sweeteners Some carbohydrates, while not sugars, are made of sugars bonded together. –Oligosaccharides/higher saccharides About 3-10 sugar units bonded together. Present in many syrups. –Polysaccharides Made of many (poly) sugar units bonded together. Example: starch
Sweeteners Sugar crystals : –Are highly ordered arrangements of sugar molecules bonded together. –Are pure; for example: Sucrose molecules bond to form sucrose crystals. Fructose molecules bond to form fructose crystals. –Are white, unless molasses or other “impurities” are trapped between crystals. –Are difficult to form or to grow large when more than one sugar is present. One way to minimize crystal growth in confections is to include a mix of different sugars in a formula.
Sweeteners Sugar crystal growth: –Is important to control when making boiled confections, made by dissolving sugar in water, then boiling to concentrate. –Sometimes: Large crystals are desired. Example: rock candy. Small, uniform crystals are desired. Examples: icings and many crystalline boiled confections, including fondant and fudge. No crystals are desired. Examples: noncrystalline boiled confections, including nut brittle, caramel; also, poured, spun, and pulled sugar.
Sweeteners Sugars are hygroscopic. –They attract and bond to water, pulling water from proteins, starches, and gums. This thins out batters and doughs.
Sweeteners –Sugars and other carbohydrates vary in their hygroscopic nature. Fructose is highly hygroscopic. Isomalt is not very hygroscopic. –Hygroscopic nature of sugar and other carbohydrates: Is sometimes desirable. examples: soft cookies, icings. Is sometime undesirable. examples: powdered sugar on doughnuts; spun or pulled sugar.
Dry Crystalline Sugars Regular granulated sugar –Extracted from sugarcane or sugar beets. –Processing involves two basic steps: Milling: extraction of inedible raw sugar from sugarcane or sugar beets. –Molasses is a by-product. Refining: removal of impurities from raw sugar. –Refiners’ syrup is a by-product. –Greater than 99.9 percent pure sucrose. Impurities can cause undesirable crystallization and browning in boiled confections; to prevent: add acid.
Dry Crystalline Sugars Regular granulated sugar –Semi-refined granulated sugar available. Less refined than regular granulated. A specialty sweetener; more expensive. Retains small amount (less than 2 percent) of refiners’ syrup. –Pale blond or gold in color. Functions like regular granulated sugar in baking. Goes by many names, including first crystallization sugar, dried cane syrup, unrefined milled sugar, natural cane juice crystals. Available as certified organic.
Dry Crystalline Sugars Coarse sugar –Also called: sanding sugar, confectioners AA (Con AA). –Large, glistening crystals. –Often >99.98 percent pure sucrose; Expensive. –May contain carnauba wax, for added sheen. –Uses: garnishing baked goods; also, clear syrups and white boiled confections.
Dry Crystalline Sugars Powdered sugar –Also called confectioners’ sugar; icing sugar in Canada. –Made from sugar finely pulverized into powder. –Contains 3 percent added cornstarch, to prevent caking. Adds a raw starch taste. –Available in different degrees of fineness. The higher the number, the greater the fineness. Examples: 6X and 10X. –Uses: uncooked icings, decorative dusting on desserts, stiffened meringues and whipped cream.
Dry Crystalline Sugars Fondant and icing sugars –Smallest grain size of any sugar (< 45 microns). Smoothest mouthfeel. –No added cornstarch. Special additives or special process prevents caking. No raw starch taste. –Uses: uncooked fondant, glazes, cream centers (pralines). –Examples: Easy Fond and Drifond.
Dry Crystalline Sugars Superfine granulated –Smaller than regular granulated sugar, larger than powdered sugar. –Also called ultrafine. –Similar in granulation to baker’s, bar, caster, and fruit sugars. –Uses: cakes (for uniform crumb), cookies (increased spread), meringue (reduced beading).
Dry Crystalline Sugars Regular (soft) brown sugar –Regular granulated sugar with a small amount (less than 10 percent) of molasses or refiner’s syrup. Sometimes contains caramel color, for darker appearance. –Soft, sticky, tends to clump. –Flavor and color of brown sugar can vary even as the amount of molasses stays the same. Examples: light brown sugar, dark brown sugar.
Dry Crystalline Sugars Regular (soft) brown sugar (cont.) –Made one of two ways: Semi-refined cane sugar dissolved in molasses and recrystallized into brown sugar. Cane molasses “painted” onto refined beet sugar. –Uses: For color and flavor; use in place of regular granulated sugar, pound for pound. –Can substitute about 1 pound (1 kilogram) molasses and 9 pounds (9 kilograms) sugar for every 10 pounds (10 kilograms).
Dry Crystalline Sugars Specialty brown sugars –Muscovado: A soft, moist brown sugar. Dark muscovado is dark, rich, and fruity tasting; high in molasses. Light muscovado also available. Brown sugar. Clockwise from top: regular light brown, dark muscovado, Demerara, and Sucanat
Dry Crystalline Sugars Specialty brown sugars –Sucanat: Short for SUgar CAne NATural Free-flowing, unrefined brown sugar. Large porous granules, not crystals. Made directly by concentration sugar cane “juice”. Brown sugar. Clockwise from top: regular light brown, dark muscovado, Demerara, and Sucanat
Dry Crystalline Sugars Specialty brown sugars –Turbinado: Large, dry, free-flowing crystals. Similar to light brown sugar in taste and color. Semi-refined; sometimes deceptively called raw, washed raw, or unrefined sugar. –Demerera: Little to no difference from turbinado. Brown sugar. Clockwise from top: regular light brown, dark muscovado, Demerara, and Sucanat