1. Recommended Viscosity (25℃, cSt)

1. Common edible vegetable oils (soybean oil, rapeseed oil, peanut oil, corn oil, etc., for normal temperature and frying):

   1000 cSt food-grade dimethyl silicone oil is the first choice. It features fast dispersion, long-lasting defoaming and foam inhibition, and will not affect the transparency and flavor of oil products.
2. Low-viscosity vegetable oil, refined salad oil and liquid palm oil:

   500 cSt is applicable for better fluidity and uniform dispersion even under low-speed stirring.
3. High-viscosity vegetable oil, hydrogenated vegetable oil and shortening (thick or semi-solid at room temperature):

   Choose 1500～2000 cSt. It resists precipitation at high temperature and delivers stable long-term defoaming performance.

Note: High-viscosity products above 3000 cSt are not recommended. They tend to agglomerate and separate in vegetable oil systems, resulting in reduced defoaming efficiency.

2. Dosage (Compliant with Food Regulations)

• Regular defoaming (foaming during stirring, conveying and filling): 1～3 ppm
• Frying process (severe foaming under high temperature and agitation): 3～5 ppm. The total dosage is advised not to exceed 5 ppm in line with food additive standards.
• Conversion reference: Add 1～5 grams of food-grade dimethyl silicone oil per ton of vegetable oil.

3. Addition & Dispersion Process (Critical Steps)

1. Pre-dilution

   Never pour the raw silicone oil directly into bulk oil. Prepare a master batch first by mixing dimethyl silicone oil with the same batch of vegetable oil at a ratio of 1:10 ~ 1:20, then stir at low speed for 5 to 10 minutes.
2. Temperature control

• Oil at room temperature: Stir at ambient temperature.
• Hot oil from pressing and refining (60～90℃): This temperature range offers the best dispersion effect. Avoid adding it when oil temperature is above 120℃ to reduce slight volatilization.

3. Stirring parameters
   Stir at medium speed (60～120 r/min) for 15 to 20 minutes to achieve homogeneous mixing. High-shear stirring is unnecessary, as it may cause secondary foaming.

4. Application Guidelines for Different Scenarios

(1) Refined finished oil (foaming during stirring, conveying and filling)

(2) Frying oil (food processing and frying production lines)

• Viscosity: Standard 1000 cSt (industry mainstream)
• Dosage: 2～5 ppm
• Supplementary addition: Add 1 ppm in batches if foaming recurs during continuous use; do not overdose at one time.

(3) Margarine, shortening and plant cream (compound systems with emulsifiers and vegetable oil)

5. Common Problems & Solutions

1. Turbidity and phase separation after addition

   Causes: Mismatched viscosity, lack of pre-dilution or insufficient stirring

   Solutions: Switch to 500 cSt or 1000 cSt product; prepare oil-based master batch and extend stirring time.
2. Good initial defoaming effect but rapid foam rebound

   Causes: Insufficient dosage or accelerated consumption of silicone oil under excessive temperature

   Solutions: Properly increase the dosage or adopt intermittent supplementary addition for high-temperature working conditions.
3. Stubborn fine foam (vegetable oil mixed with protein and other additives)

   Dimethyl silicone oil is mainly used to eliminate large bubbles and inhibit foaming. For dense fine foam, compound with food-grade polyether defoamer if permitted by relevant regulations.

6. Important Compliance Reminders

• Only food-grade dimethyl silicone oil (E900) can be used for edible vegetable oil. Industrial grade is strictly prohibited.
• Keep the total dosage within the limit specified by food additive regulations.