In the field of baking and food processing, custard powder (also known as egg yolk powder) and baking powder are two commonly used food additives. Although they have similar names, they have significant differences in ingredients, functions and applications. Custard powder is mainly used for flavoring and thickening, giving food a rich milky flavor and smooth taste; while baking powder is a chemical leavening agent that expands dough or batter by producing gas.
1. Characteristics and applications of custard powder
1.1 Basic ingredients and characteristics
Custard powder is a premixed powder, the main ingredients of which include:
Corn starch: as a thickener, providing a smooth texture.
Dairy products (milk powder, whey powder): give milky flavor.
Vanilla essence or egg yolk powder: enhance aroma and color.
Sugar: some products contain sugar and can be directly seasoned.
It is characterized by strong solubility, light yellow color, rich milk and egg aroma, and is often used to make dessert fillings or sauces.
1.2 Function and mechanism of action
Thickening: Corn starch gelatinizes when heated to form a gelatinous structure (such as custard sauce).
Fragrance: Dairy and vanilla ingredients provide a flavor similar to egg and milk.
Improve taste: Make fillings or sauces more delicate and dense.
1.3 Common application scenarios
Baking fillings: Used to make puff fillings and cake toppings (such as custard sauce).
Dessert making: mango pudding, egg tart liquid, mousse cake base.
Beverage flavoring: Increase the concentration of milk flavor in milk tea and milkshakes.
1.4 Usage and precautions
Mixing ratio: Usually mix at 1:5 (custard powder: water or milk), heat to about 80°C and stir until viscous.
Avoid caking: Mix with cold water before heating.
Alternative: You can make it yourself with egg yolk + milk + starch, but the flavor is slightly inferior.
2. Characteristics and applications of baking powder
2.1 Basic ingredients and types
Baking powder is a chemical leavening agent, the main ingredients of which are:
Acidic salts (such as sodium dihydrogen pyrophosphate, potassium hydrogen tartaric acid).
Alkaline salts (usually sodium bicarbonate, i.e. baking soda).
Bulking agent (corn starch, to prevent premature reaction).
According to the reaction speed, it is divided into:
Single-effect baking powder: produces gas immediately when it comes into contact with water, and needs to be baked quickly (such as pancakes).
Double-effect baking powder: produces gas partially when it comes into contact with water, and reacts again when heated (more commonly used).
2.2 Function and mechanism of action
Baking powder produces carbon dioxide (CO₂) through acid-base reaction, which makes the batter expand:
Wet reaction: Acidic salts and sodium bicarbonate produce a small amount of CO₂ when they come into contact with water.
Thermal reaction: The remaining acidic salts react further when heated, and continue to produce gas.
2.3 Common application scenarios
Cakes and muffins: provide fluffy texture (such as sponge cakes, muffins).
Fried foods: make fried dough sticks and donuts crispier.
Yeast-free pastries: quickly make scones and muffins.
2.4 Usage and precautions
Amount added: usually 1-3% of the flour, too much will make it bitter.
Mix well: need to mix with dry powder materials first to avoid local high concentration.
Alternatives: yeast (requires fermentation time) or whipped egg whites (such as angel food cake).
3. Comparison between custard powder and baking powder
| Custard powder | Baking powder | |
| Main functions | Thickening, Flavoring | Bulking, Gas production |
| Core ingredients | Starch, Dairy products, Flavors | Acidic salts, Baking soda, Starch |
| Applicable scenarios | Fillings, Sauces, Desserts | Cakes, Biscuits, Fried foods |
| Chemical action | Physical gelatinization (heating) | Acid-base reaction (CO₂ production) |
| Usage restrictions | High temperature and long cooking may cause water to return | Excessive use may cause bitterness or aluminum residue (baking powder containing aluminum) |
4. Combined use cases and recipe examples
4.1 Milky small cake (custard powder + baking powder)
Recipe: 100g low-gluten flour + 20g custard powder + 3g baking powder + 1 egg + 50ml milk.
Steps: Mix the dry powder and add the wet material and stir well.
Baking powder produces gas to make the cake bulky, and custard powder adds milky flavor.
4.2 Precautions
Sequence: Custard powder needs to be prepared first, and baking powder is directly mixed into the dry powder.
Temperature control: Custard sauce should not be heated above 85°C, and baking powder should be baked in the oven as soon as possible.
5. Safety and purchase recommendations
5.1 Custard powder
Choose natural flavor products without added flavors (such as those containing real egg yolk powder).
People with lactose intolerance need to pay attention to the ingredient list.
5.2 Baking powder
Prefer “aluminum-free baking powder” (such as marked “aluminum content ≤ 0.1%) to avoid the risk of long-term intake of aluminum.
Check the shelf life: the effect decreases after being exposed to moisture.
6. Conclusion
Cust powder and baking powder each have their own functions in food processing:
Custard powder is a shaper of flavor and texture, suitable for scenes that require milky aroma and consistency;
Baking powder is a structural engineer, giving food a fluffy taste through chemical reactions.
Correctly understanding the differences between the two and using them reasonably can significantly improve the quality of baked products. For home users, it is recommended to always have double-effect aluminum-free baking powder and pure natural custard powder on hand to meet diverse cooking needs.
FAQ
What is the fundamental difference between custard powder and baking powder in baking?
The fundamental difference lies in their core ingredients, functional roles, and underlying mechanisms:
Custard Powder (Flavoring & Thickening Agent): A premixed compound consisting primarily of cornstarch, dairy powders (milk/whey powder), vanilla or egg yolk flavoring, and food coloring. It works through physical gelatinization when heated, acting as a “flavor and texture shaper” to provide a smooth, dense, milky, and golden-yellow finish in fillings, sauces, and puddings.
Baking Powder (Chemical Leavening Agent): A chemical aerating agent composed of sodium bicarbonate (alkali), acidic salts, and starch. It works through an acid-base neutralization reaction that generates carbon dioxide (CO2) gas upon contact with moisture and heat, acting as a “structural engineer” to make cakes, biscuits, and batters light, fluffy, and porous.
Can custard powder replace baking powder in a recipe, or can they be used together?
Custard powder and baking powder cannot be substituted for one another, but they are frequently used together in baking to complement each other’s functions:
Substitution: Custard powder cannot replace baking powder because it contains no chemical leavening agents and will fail to expand or aerate dough. Conversely, baking powder cannot replace custard powder because it lacks starch thickeners and dairy flavorings, and adding excess baking powder will impart a bitter chemical taste.
Combined Usage: They can be combined safely (e.g., in specialty cakes, cookies, and dessert batters) to achieve dual benefits—baking powder provides the necessary structural expansion (CO2 gas production), while custard powder enhances the golden color, soft crumb, and rich milky-vanilla aroma.
Application Technique: Baking powder should be sifted directly with dry flour (typically 1–3% of flour weight), while custard powder can be mixed into dry ingredients or whisked with liquid (1:5 ratio with water/milk) and heated to ~80℃ for thickening sauces and fillings.
