Hydrophilic-lipophilic balance (HLB)

Generally, the emulsifier with strong hydrophilicity becomes an oil / water type emulsion, and the emulsifier with strong lipophilicity becomes an water / oil type emulsion. In order to express the hydrophilic-lipophilic balance of the emulsifier, the HLB value (hydrophilic-lipophilic balance value) is usually used, and the hydrophilicity of the emulsifier is expressed by the HLB value. There are various calculation methods for the HLB value,

Difference formula: HLB = hydrophilicity of hydrophilic group-hydrophobicity of lipophilic group
Ratio formula: HLB = hydrophilic hydrophilicity / lipophilic hydrophobicity

The HLB value of each emulsifier can be determined by experimental methods. An emulsifier with a lipophilicity of 100% is required. Its HLB is 0 (represented by paraffin), and the HLB of 100% hydrophilic is 20 (as potassium oleate As a representative), it is divided into 20 equal parts to indicate the strength of its hydrophilicity and lipophilicity. The larger the HLB value, the stronger the hydrophilicity, and the smaller the HLB value, the stronger the lipophilicity.

Most edible emulsifiers are nonionic surfactants with HLB values of 0-20. The different HLB values and related properties of nonionic emulsifiers are shown in the table; HLB values of ionic surfactants are 0-40 . Therefore, emulsifiers with an HLB value <10 are mainly lipophilic, while emulsifiers with an HLB value ≥10 have hydrophilic characteristics.

For mixed emulsifiers, the HLB value is additive. Therefore, when two or more emulsifiers are mixed and used, the HLB value of the mixed emulsifier can be obtained according to the mass fraction of each emulsifier of its composition:

HLBa, b = HLBa · A% + HLBb · B%
In the formula, HLBa and b are the HLB values of emulsifiers a and b; HLBa and HLBb are the HLB values of a and b emulsifiers; A% and B% are a and b in the mixed emulsifier % Content (this formula is only applicable to non-ionic emulsifiers).