Mayonnaise, custard sauce, margarine, and butter are all basic sauces or fats used in Western cooking and baking. However, they differ fundamentally in their ingredients, texture, and uses.
The following table can help you quickly grasp their core differences:
| Sauces/Oils | Core Ingredients | Taste and Flavor | Primary Uses |
| Mayonnaise (Mennas) | Plant oil, egg yolks, vinegar/lemon juice | Cold food sauce, smooth, sour, refreshing | Cold dish sauces: salad dressings (potato and egg salad), spreading on sandwiches, dipping sauce for fried foods |
| Custard Sauce (Cheese Sauce) | Milk, egg yolks, sugar, flour/corn starch | dessert filling, smooth and creamy, rich milk flavor, thick texture | Sweet filling for desserts： filling of pastries， cake layers， bread fillings， paired with fruits |
| Vegetable Butter (Plant Butter) | Plant oil (partially hydrogenated)， water， emulsifier, etc. | Lighter in flavor, texture may be similar to or softer than butter， may have trans fat risk | Butter substitute： spreading on bread， baking， frying， lower cost |
| Butterfat Butter (Animal Butter) | Extracted milk fat (fat content ≥ 80%) | Strong natural milk aroma， uniform and细腻 texture， available in salted and unsalted varieties | Core baking and cooking： making cakes， cookies， grilling steak， spreading on bread， making sauces |
Dive deeper into these four sauces
After understanding the basic differences， let's take a look at their unique features to help you make more precise choices when cooking.
Mayonnaise
• Identity： A cold-prepared condiment， also transliterated as "Mayonnaise".
• Principle： It uses lecithin in egg yolks as the "emulsifier" to encapsulate a large amount of plant oil in the water phase formed by vinegar or lemon juice， forming a stable "water-in-oil" emulsion.
• Why cold： Because mayonnaise is usually made with raw egg yolks and is generally not heated， so it is mainly used for cold dishes. Therefore， its shelf life is very short. Homemade mayonnaise needs to be consumed as soon as possible.
• Calorie bomb： Its main ingredient is plant oil， so it has very high calories. One tablespoon (about 15 grams) of mayonnaise can have more than 100 calories.
Custard Sauce
• Identity： A heated sweet sauce， also known as "Custard Sauce" or "Klinem Sauce".
• Principle： By heating， the mixture of egg yolks， milk， and sugar becomes thick and smooth under the action of starch.
• Difference from Mayonnaise： Custard sauce is a hot-prepared sweet sauce， mainly used for filling desserts； while mayonnaise is a cold-prepared salty/acid sauce， used for seasoning cold dishes. This is the most fundamental difference between them.
• Transformation： During the process， if whipped cream is added， it can become a lighter "Diplomat Sauce"， used as the filling for Napoleon cakes.
Butter (Butter) vs. Margarine (Margarine)
These two are often compared. Their main difference lies in "origin" and "health".
• Different origins：
o Butter is natural animal fat， simply put， it is extracted from milk.
o Margarine is artificial plant oil， processed through various techniques such as hydrogenation or crystallization to imitate the properties of butter.
• How to distinguish：
o Smell： Butter has a natural milk aroma， while the aroma of margarine is usually relatively weak.
o Look： Butter in the refrigerated state has a hard texture， while some margarine， even after refrigeration， still maintains good spreading properties. o Conduct the experiment: Take a small piece and rub it in your palm. The buttery cream will gradually melt, giving a feeling similar to applying hand cream; while the artificial butter may still have some residue on your hands.
• Health reminder:
o During the manufacturing process of artificial butter, if the hydrogenation of vegetable oil is not complete, trans fatty acids may be produced. Long-term and excessive intake is detrimental to cardiovascular health. When purchasing, you can pay attention to the nutrition label and choose products labeled "0 trans fats".
o It should be clearly stated that although buttery cream is natural, it is still a high-fat food and also requires moderation in consumption.
Post time: Feb-25-2026