COMMODITIES
Chapter 1: Wheat and Starchy Ingredients
Composition, Production, Grade, and Quality
Composition of the Wheat Kernel The wheat kernel, or grain, is the source of all wheat flours and consists of three main parts: the endosperm, the bran, and the germ.
Endosperm: This is the largest part (about 83% of the kernel) and is primarily composed of starch and protein. When milled, this becomes the white flour used in most baking. The proteins here are the key to forming gluten when mixed with water.
Bran: The tough, protective outer layer (about 14% of the kernel). It is high in dietary fiber and B vitamins. In baking, bran can interfere with gluten development, resulting in denser products.
Germ: The embryo or reproductive part of the kernel (about 3%). It is rich in fat, B vitamins, and vitamin E. Due to its high fat content, it is often removed during milling to prevent the flour from going rancid quickly.
Wheat Production and Milling Wheat is harvested and then undergoes a sophisticated process called milling to separate the kernel components and grind the endosperm into flour. The process generally involves:
Cleaning: Removing impurities like stones and other grains.
Conditioning: Adding a controlled amount of water to temper the wheat, making the bran easier to remove and the endosperm easier to grind.
Breaking: The conditioned wheat passes through a series of rollers that crack the grain open, separating the endosperm from the bran and germ.
Sifting (Sieving): The broken material is sifted to separate the large bran flakes from the finer endosperm particles.
Reduction: The remaining endosperm pieces are gradually ground down into fine flour.
Blending and Enrichment: Different streams of flour are blended to achieve specific protein levels, and often enriched with vitamins and minerals lost during milling.
Grade and Quality of Wheat Wheat is primarily graded based on its hardness, planting season, and protein content, which determines its best use.
Hard Wheat: High in protein and gluten-forming potential. Used for bread, rolls, and other products requiring strong structure. Examples include Hard Red Spring and Hard Red Winter wheat.
Soft Wheat: Low in protein and gluten. Used for tender products like cakes, cookies, and pastries. Examples include Soft Red Winter and Soft White wheat.
Ash Content: This measures the mineral content of the flour, which comes from the bran layer. A lower ash content indicates whiter, purer flour (less bran contamination), while a higher ash content indicates a darker, higher-extraction flour.
Wheat Products
Types of Wheat Flours The primary product of wheat is flour, classified by its protein level and treatment:
Bread Flour: High protein content (typically 12-14%). This is necessary to create strong, elastic gluten structures capable of holding the gases produced by yeast.
All-Purpose Flour (Plain Flour): Medium protein content (around 10-12%). A versatile blend suitable for a wide range of products, though not ideal for professional high-volume bread or delicate cakes.
Cake Flour: Low protein content (about 7-9%). It is highly refined and often bleached, resulting in a very fine, soft flour that produces tender, light cakes.
Pastry Flour: Slightly higher protein than cake flour (around 9-10%). Used for tender products that require a bit more structure, like pie crusts and some cookies.
Whole Wheat Flour: Contains the entire wheat kernel—bran, germ, and endosperm. Its high fiber and fat content interfere with gluten formation, making baked goods denser and less elastic than those made with white flour.
Other Flours, Meals, and Starches
Other Flours and Meals While wheat is dominant, other grains and legumes are processed into flours and meals, each offering unique flavour and texture:
Rye Flour: Low in gluten-forming proteins but high in pentosans, which can absorb a large amount of water. It is used to make distinctive rye breads, often combined with high-gluten wheat flour.
Cornmeal: A coarse meal ground from dried maize. Used for corn bread, polenta, and as a dusting agent.
Rice Flour: Made from finely milled rice. It is naturally gluten-free, used in specific confectionery items and as a thickener.
Starches Starches are carbohydrates primarily extracted from grains (like corn, wheat, rice) or tubers (like potato, tapioca). In bakery and confectionery, their main role is thickening and gelling.
Corn Starch: A common thickener for sauces, gravies, and fruit pie fillings. It must be mixed with a cold liquid before being added to hot mixtures to prevent clumping.
Potato Starch and Tapioca Starch: Used similarly to corn starch, offering slightly different textures and clarity. Tapioca starch is particularly good for thickening fruit fillings where a glossy appearance is desired.
Chapter 2: Sugar, Cocoa, and Sweeteners
Sugar Substitutes
Sugar substitutes are ingredients used to replace sucrose (table sugar), often to reduce caloric content or manage blood sugar levels. They can be broadly divided into two groups:
High-Intensity Sweeteners (Artificial/Non-Nutritive): These compounds are hundreds or thousands of times sweeter than sugar and are used in very small amounts. They contribute sweetness but do not provide the bulk, moisture, or browning properties of sugar, making them challenging for structural baking. Examples include Aspartame and Sucralose.
Bulk Sweeteners (Sugar Alcohols): These include ingredients like Sorbitol, Xylitol, and Erythritol. They provide bulk and often have cooling effects, making them useful in sugar-free confectionery and chewing gums. However, they may cause digestive upset in large quantities.
Natural Sweeteners: Derived from plants, such as Stevia (from the stevia plant) or Monk Fruit extract. These are often intensely sweet and are used in concentrated forms.
Syrups, Jams, and Marmalades
Syrups Syrups are concentrated solutions of sugar in water, often containing other flavouring agents or sugars. They play a critical role in confectionery and baking:
Glucose Syrup (Corn Syrup): Used primarily to prevent the crystallization of sucrose, ensuring a smooth texture in candies, glazes, and ice creams. It also helps retain moisture in baked goods.
Invert Sugar: Created by hydrolyzing (breaking down) sucrose into its component simple sugars, glucose and fructose. It is sweeter and helps maintain moisture better than sucrose, often used in fondants and premium baked goods to improve shelf life.
Maple Syrup/Honey: Natural syrups that provide distinct flavours and act as humectants (moisture retainers).
Jams and Marmalades These are sweet spreads preserved by sugar. The setting ability is primarily due to the natural gelling agent, pectin, found in fruit, particularly in citrus rinds and apples.
Jam: Made from whole or cut fruit pulp mixed with sugar and often acid (lemon juice) to achieve the necessary pH for gelling.
Marmalade: Specifically made from citrus fruit, including the peel, which provides bitterness and a high pectin source.
Cocoa Production
Cocoa, derived from the seeds of the Theobroma cacao tree, is fundamental to chocolate and many confectionery items. The production process transforms the bitter seed into the familiar cocoa product.
Harvesting: Ripe pods are hand-picked from the tree.
Fermentation: The beans, still encased in white pulp, are heaped and covered. This crucial stage develops the chocolate flavour and reduces astringency. The temperature rises, killing the germ and initiating chemical changes.
Drying: The fermented beans are dried in the sun or by machines to reduce moisture content for stability.
Roasting: The dried beans are roasted to fully develop flavour precursors created during fermentation. The shell separates easily after roasting.
Grinding (Nibs): The beans are cracked, and the outer shells are removed, leaving the inner pieces called nibs.
Milling/Liquefaction: The nibs are ground. The friction generates heat, melting the high fat content, turning the nibs into a thick liquid known as cocoa mass or cocoa liquor.
Cocoa By-products
The cocoa mass is the starting point for all chocolate and cocoa products.
Cocoa Liquor (Mass): The non-alcoholic, liquid state of ground cocoa nibs. It contains both cocoa solids and cocoa butter.
Cocoa Butter: This is the fat component of the cocoa bean, extracted from the cocoa mass using a hydraulic press. It is a solid fat at room temperature, giving chocolate its snap and smooth melt. It is essential for making white chocolate and is often added back to dark chocolate to improve texture.
Cocoa Powder: What remains after the cocoa butter has been pressed out of the liquor. It is the dry, non-fat portion. It is graded by fat content and processed in two ways:
Natural Cocoa Powder: Lighter in colour and acidic. Used with baking soda in recipes that require an acidic component for leavening.
Dutch-Process Cocoa Powder: Treated with an alkaline solution to neutralize the acid. It is darker, milder in flavour, and mixes more easily with liquids, but requires baking powder (not soda) for leavening.
Chapter 3: Eggs and Dairy Products
Types
Eggs While various birds lay eggs, chicken eggs are the standard in baking and confectionery. They are composed of three main parts:
Yolk: Contains almost all the fat, 1/3 of the protein, and vitamins A, D, and E. Its high fat content makes it an excellent emulsifier (a substance that helps blend fats and liquids).
White (Albumen): Composed almost entirely of water and protein. Its primary role is to provide structure when coagulated by heat and to leaven products when whipped into a foam (meringue).
Shell: The porous protective layer.
Dairy Products Dairy products are derived from the milk of mammals, most commonly cows.
Milk: Available in various fat levels (whole, skim, 2%). It provides moisture, richness, and aids in browning due to the presence of lactose (milk sugar).
Evaporated Milk: Whole milk with about 60% of its water removed.
Condensed Milk: Evaporated milk that has been heavily sweetened, used in candies and fillings.
Cream: The fat layer skimmed from the top of milk. Grading is based on fat content (e.g., whipping cream, heavy cream).
Butter: Created by churning cream, separating the milk solids and water from the milk fat. It provides superior flavour, tenderness, and flakiness due to its unique melting characteristics.
Cheese: Coagulated milk proteins (casein), less commonly used than butter or milk, but essential in products like cheesecakes and savoury pastries.
Importance in Bakery and Confectionery
Eggs and dairy products are multifunctional ingredients, serving several crucial roles:
Roles of Eggs
Structure and Coagulation: Egg proteins set when heated (coagulation), providing the primary structure for items like custards, cakes, and meringues.
Leavening: When egg whites are whipped, they trap air bubbles, creating a foam that acts as a leavening agent for sponge cakes and soufflés.
Emulsification: The lecithin in the yolk acts as a natural bridge between fat and water, creating stable mixtures (emulsions) crucial for batters, sauces (like hollandaise), and rich ice creams.
Moisture, Flavor, and Colour: Eggs contribute liquid, rich flavour, and colour (from the yolk) to baked goods.
Roles of Dairy
Moisture and Texture: The water content in milk hydrates flours and sugars.
Fat (Butter): Essential for shortening (tenderizing by coating gluten) and creating flaky layers in laminated doughs. It also provides the rich, desirable flavour associated with quality baked goods.
Enrichment: Milk solids contribute to nutritional value and enhance flavour.
Browning (Maillard Reaction): Lactose, the sugar in milk, is largely responsible for the desirable golden-brown colour of crusts.
Grading, Quality, and Selection
Egg Grading Eggs are graded by the USDA (or equivalent) based on their exterior (cleanliness, shape) and interior quality (yolk shape, thickness of white). The most common grades are:
Grade AA: The highest quality. Thick, firm whites, high round yolks. Ideal for frying and poaching where appearance matters.
Grade A: Slightly thinner whites. Suitable for most baking applications.
Grade B: Used primarily in liquid egg products.
Dairy Quality and Selection
Pasteurization: All fluid milk and many dairy products must be pasteurized (heated to destroy harmful bacteria) for safety.
Fat Content: A key quality metric. High-fat dairy products (like heavy cream and butter) are essential for richness and stability in creams, sauces, and doughs. Unsalted butter is preferred in baking, as it allows the baker precise control over the salt content.
Chapter 4: Leavening Agents
Leavening agents are substances used in doughs and batters that create gases, causing the mixture to rise, resulting in a lighter, softer, and more palatable product.
Yeast and Its Varieties
Yeast is a single-celled fungus that acts as a biological leavening agent. It consumes simple sugars and converts them into two main by-products: carbon dioxide (CO2) gas and ethyl alcohol (which evaporates during baking). This process is called fermentation.
Yeast Varieties
Fresh/Compressed Yeast: Sold as small, moist blocks. It is highly active but perishable and must be refrigerated. It is preferred by some professional bakers for its reliable, mild flavour.
Active Dry Yeast: Dormant yeast encased in granules. It must be proofed (dissolved in warm water and allowed to foam) before use to confirm its viability and rehydrate the cells.
Instant Dry Yeast (IDY): A more finely granulated and porous version of dry yeast. It can be mixed directly into the dry ingredients without proofing, making it convenient and fast-acting.
Role in Raising Bakery Products
The role of yeast is multifaceted, going beyond simple gas production:
Gas Production: The CO2 gas produced by fermentation is trapped by the elastic gluten network in the dough, causing it to rise (leaven).
Gluten Development: The slow, controlled rise produced by yeast allows time for enzymes in the dough to modify the proteins, aiding in the development of a strong, extensible gluten network.
Flavor Development: The by-products of fermentation (including organic acids and alcohols) contribute the distinct, complex, and desirable flavour profile of quality bread.
Chemical Leavening Agents
Chemical leavening agents react quickly to moisture and/or heat to produce CO2 gas, providing a rapid rise suitable for quick breads, cakes, and cookies.
Baking Soda (Sodium Bicarbonate, NaHCO3):
It is a pure alkaline compound.
It requires an acid (like buttermilk, yogurt, vinegar, lemon juice, or molasses) to react and release CO2 gas.
Reaction is immediate upon mixing. If no acid is present, it will leave a bitter, soapy taste.
Baking Powder:
It is a complete leavening agent containing: Baking Soda (NaHCO3), a dry acid (e.g., Cream of Tartar), and a starch (e.g., cornstarch) to keep the other two ingredients dry and free-flowing.
Single-Acting Baking Powder: Reacts immediately upon contact with moisture.
Double-Acting Baking Powder: Has two acids. One reacts upon mixing with moisture, and the second requires heat to react, providing a second boost of leavening during baking. This provides insurance and a reliable final rise.
Ammonium Bicarbonate (Ammonia):
Used in products with very low moisture content, like some cookies and crackers.
It releases both CO2 and ammonia gas upon heating. Since the ammonia must completely evaporate, it is only suitable for thin, crisp products where the gas can escape easily.
Chapter 5: Shortenings
Shortening is a general term for any fat used in baking to "shorten" the gluten strands, which makes the finished product tender and crumbly.
Role of Shortening
Shortenings are fundamental to the texture, flavour, and structure of baked goods.
Tenderization (Shortening): Fat coats the flour particles, preventing the full hydration of the gluten-forming proteins. This results in shorter, weaker gluten strands and thus a more tender, less chewy crumb.
Flakiness: In laminated doughs (like puff pastry or croissants), layers of fat melt during baking, creating gaps and layers of steam, which results in the characteristic flakiness.
Moisture Retention: Fats help to seal moisture into the product, extending shelf life and preventing staling.
Emulsification: Some shortenings contain emulsifiers (like mono- and diglycerides) that help create stable, smooth batters, allowing them to hold more liquid and sugar.
Flavour: Butter provides a superior, rich flavour that is often the primary reason for its selection over other fats.
Types of Shortening
Shortenings vary based on their source (animal or vegetable) and their melting point.
Butter: Dairy fat, containing about 80% fat, 18% water, and 2% milk solids. It has a low melting point, contributing to its superior flavour and 'melt-in-your-mouth' texture.
Margarine: A non-dairy fat substitute made from vegetable oils and water, formulated to mimic butter. It is usually higher in emulsifiers and water content than butter.
Lard: Rendered pig fat. It produces exceptionally flaky pastry due to its unique crystalline structure and wide plasticity range (remaining workable over a large temperature range).
Vegetable Shortening (e.g., Crisco): Solid fat made from hydrogenated vegetable oils (like soybean or palm). It is 100% fat, has a high melting point, and contains emulsifiers. It is flavourless and produces excellent volume in cakes and very tender crusts.
Oils (Liquid Fats): Fats like canola, corn, or olive oil. They tenderize efficiently but cannot be creamed or rubbed in, resulting in different textures (often moist, but not flaky) than solid fats.
Usage in Bakery and Confectionery
The method of incorporating the shortening drastically affects the final product texture:
Creaming Method: Solid fat (like butter) and sugar are beaten together until light and fluffy. This traps air bubbles, which are a primary source of leavening in cakes and cookies.
Rubbing-In Method (or Cut-In): Cold, solid fat is cut into flour until coarse crumbs form. This coats the flour minimally, resulting in the desired flaky texture for scones, biscuits, and pie crusts.
Lamination: The process of folding a solid block of fat (butter or margarine) into a dough multiple times to create alternating thin layers of fat and dough, essential for puff pastry, Danish, and croissants.
Melting: Fat is simply melted and mixed with other liquids, often used in chewy cookies or brownies where tenderness is achieved without incorporating air.
Chapter 6: Gelling Agents, Stabilizers, and Additives
Gelling Agents and Stabilizers
These ingredients are crucial for controlling the texture and stability of creams, fillings, and confectionery.
Gelling Agents Gelling agents, or hydrocolloids, absorb water and form a gel, which is a semi-solid network that holds liquid.
Pectin: A natural polysaccharide found in the cell walls of fruit, particularly citrus and apples. It requires sugar and acid (low pH) to form a strong gel, making it ideal for jams and jellies.
Gelatin: A protein derived from animal collagen. It dissolves in hot water and sets as it cools, creating a heat-reversible gel. Used in mousses, glazes (nappage), and panna cotta.
Agar-Agar: A vegetarian alternative to gelatin, derived from seaweed. It creates a firmer, heat-stable gel that does not melt at room temperature.
Starches: (As discussed in Chapter 1) Act as gelling agents when heated in liquid, forming thick pastes or firm custards (e.g., corn starch in pastry cream).
Stabilizers Stabilizers help maintain the homogeneity and texture of products, preventing separation and breakdown.
Gums (e.g., Xanthan, Guar): These are natural carbohydrate polymers that greatly increase the viscosity of liquids, even in small amounts. Used to prevent ice crystal formation in ice cream, stabilize fruit purees, and provide structure in gluten-free baking.
Emulsifiers: Substances that help immiscible ingredients (like oil and water) mix and stay mixed. Eggs (lecithin), mono- and diglycerides in commercial shortenings, and soy lecithin are common examples used to prevent fat separation in batters and chocolate.
Food Additives and Preservatives
Food additives are substances intentionally added to food to achieve a desirable effect.
Preservatives: These are added to extend the shelf life by inhibiting the growth of microorganisms (like mold and bacteria) or slowing down chemical reactions (like oxidation).
Anti-microbials (e.g., Sorbates, Calcium Propionate): Used in bread and high-moisture baked goods to inhibit mold growth.
Anti-oxidants (e.g., Ascorbic Acid): Added to fats and oils to prevent rancidity (oxidation) and help maintain the colour of fruit fillings.
Colourants and Flavour Enhancers: Used to improve the sensory appeal of confectionery and baked items.
Thickeners and Texturizers: These overlap with gelling agents and stabilizers, ensuring consistent mouthfeel and texture.
Edible Garnishes
Garnishes are elements added primarily for visual appeal, contrast in texture, and minor flavour enhancement.
Glazes and Icing: Thin coatings applied to the surface for shine, protection, and sweetness.
Nuts and Seeds: Can be used whole, sliced, or chopped. They add crunch and rich, complementary flavours.
Chocolate: Shavings, curls, or dust used on cakes, tortes, and hot beverages.
Fruits: Fresh, candied, or dried fruit used to add colour and freshness.
Dusting and Coarse Sugars: Fine powdered sugar (icing/confectioner's sugar) or large crystal sugars (sanding sugar) used to top baked goods immediately before or after baking.
Chapter 7: Food Laws, Storage, and Modern Ingredients
Introduction to Food Laws
Food laws are established by governmental and international bodies to ensure food safety, prevent fraud, and provide consumers with accurate information. While specific laws vary by country, the fundamental principles are universal.
Food Safety and Hygiene: Laws mandate strict hygiene practices in food handling, production, and storage to prevent contamination and foodborne illnesses. This includes requirements for sanitation, temperature control, and employee health.
Labeling Requirements: Labels must accurately list ingredients in descending order of weight, clearly identify all major allergens (like milk, eggs, nuts, wheat), and provide nutritional information (calories, fat, sugar, etc.).
Standard of Identity: These are legal definitions that establish what a specific food product must contain to be called by that name (e.g., defining what constitutes "whole wheat bread" or "ice cream").
Storage and Preservation of Bakery and Confectionery Products
Proper storage is critical to maintaining the quality, safety, and shelf life of finished products.
Staling (Baked Goods): This is the primary concern for bread and cakes. It is caused by the retrogradation of starch molecules (recrystallization). To prevent it:
Keep Airtight: Prevents moisture loss, which accelerates staling.
Freezing: Freezing halts the staling process and is the best long-term solution.
Avoid Refrigeration: For most bread, refrigeration accelerates staling.
Preservation for Confectionery: High sugar content in candies, jams, and fondants acts as a natural preservative by reducing water activity, making it inhospitable for microbes. Storage must focus on protecting against humidity, which can cause sugar to dissolve and crystallize.
Fat Rancidity: Fats and oils (in shortenings, butter, or chocolate) can oxidize and become rancid, producing off-flavours. Products must be stored in cool, dark conditions to slow this chemical reaction.
Organic and Genetically Modified Foods
These are two concepts that impact ingredient sourcing and consumer choices.
Organic Foods Organic certification generally dictates that ingredients were grown and processed without:
Synthetic pesticides and fertilizers.
Genetic modification.
Ionizing radiation.
Sewage sludge.
For bakery ingredients, organic flour, sugar, and dairy are produced under these guidelines.
Genetically Modified Foods (GMF) GMFs, or genetically engineered (GE) foods, are those derived from organisms whose genetic material (DNA) has been altered in a way that does not occur naturally.
Examples in Baking: Common ingredients derived from genetically modified crops include corn (for corn starch and syrup) and soy and canola (for oils and shortenings).
Implications: The debate surrounding GMFs often centers on increased yield, pest resistance (making farming more efficient), and environmental impact versus concerns over long-term human health effects and the impact on biodiversity. Labeling laws for GMFs vary significantly worldwide.
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