1. Types of Gelatin
Gelatin Sheets: Need to be softened before dissolving, easy to handle.
Gelatin Powder: Needs to be mixed with water before use, suitable for applications requiring even distribution.
2. Viscosity Selection
High Viscosity: Suitable for cakes requiring a firm structure, such as mousse or mirror glaze cakes.
Low Viscosity: Suitable for cakes with a light texture, such as jelly layers or fillings.
3. Gel Strength Selection
High Gel Strength: Suitable for cakes that need to set quickly, such as mousse.
Low Gel Strength: Suitable for cakes that need to set slowly, such as jelly layers.
4. Usage Ratio
Gelatin Sheets: Typically 5-10 grams per 500 grams of liquid.
Gelatin Powder: Typically 5-10 grams per 500 grams of liquid.
5. Precautions
Dissolution Temperature: Gelatin should be dissolved in warm water at 40-50°C to avoid overheating, which can damage its structure.
Acidic Environment: Acidic ingredients (such as lemon juice) can reduce the gelling effect of gelatin, so the amount used should be adjusted accordingly.
6. Substitutes
Agar: Suitable for vegetarians, sets at a higher temperature.
Pectin: Suitable for making jelly or jam.
 

Summary
High Viscosity, High Gel Strength: Suitable for cakes requiring a firm structure.
Low Viscosity, Low Gel Strength: Suitable for cakes with a light texture.
Choose the appropriate type and amount of gelatin based on the cake's requirements to ensure the best results.