How does craft beer equipment use hydrogen peroxide to sterilize?

1. The physical and chemical properties of stable hydrogen peroxide and the principle of disinfection and sterilization

Hydrogen peroxide, scientific name hydrogen peroxide, molecular formula H2O2, molecular weight 34.01, colorless transparent liquid, soluble in water, alcohol and ether, corrosive at high concentrations, when placed in an open place, it will gradually decompose into oxygen and water, 30% hydrogen peroxide has a density of 1.11g/cm3, a melting point of -0.89℃, and a boiling point of 151.4℃.It has a strong bactericidal effect, and the effect is more obvious under the alkaline conditions of home-brewed beer equipment.

Stable hydrogen peroxide is a colorless, odorless, and non-toxic transparent liquid that has been synergistically and stably treated. Due to the synergistic effect of hydrogen peroxide and synergists, the ability and speed of sterilization and virus killing are greatly improved, and its bactericidal effect is more long-lasting.The principle of sterilization is to use the extremely strong oxidation capacity of reactive oxygen species to destroy the protoplasm in the body of microorganisms, thereby achieving the purpose of killing microorganisms and disinfection and sterilization.Stable hydrogen peroxide has the characteristics of broad-spectrum, high-efficiency and long-lasting sterilization. After the sterilization process is completed, it is decomposed into oxygen and water, which will not produce toxic residues. It does not need to be rinsed with water and is non-polluting to the environment. It is an environmentally friendly disinfectant.

2. Important factors affecting the stability of hydrogen peroxide

The important factors that affect the stability of hydrogen peroxide are the following：

1. Temperature.Hydrogen peroxide is relatively stable at lower temperatures and higher purities in home-brewed beer equipment.When hydrogen peroxide is heated to a temperature of 153℃ or higher, violent explosive decomposition occurs.At lower temperatures, the decomposition of hydrogen peroxide is relatively stable, and the decomposition reaction is: 2H2O2→2H2O+O2++46.94kcal.

2. PH value.The pH of the medium has a great influence on the stability of hydrogen peroxide.Under acidic conditions, the properties of hydrogen peroxide are very stable, and the oxidation reaction rate is slow; in alkaline media, hydrogen peroxide is very unstable and the decomposition rate is very fast.

3. Impurities.Impurities are the main factor affecting the stability of hydrogen peroxide.Many metal ions, such as divalent iron ions, divalent manganese ions, divalent copper ions, and trivalent chromium ions, will promote the decomposition of hydrogen peroxide.Usually a large number of stabilizers are added to hydrogen peroxide to inhibit the catalysis of impurities. The principle of inhibition is chelation and reduction.That is, adding trace amounts of stabilizers, such as sodium stannate, sodium pyrophosphate or 8-hydroxyquinoline, are used to inhibit the decomposition of hydrogen peroxide through reduction and complexation.

4. Light.Light with a wavelength between 3200 and 3800 angstroms will accelerate the decomposition rate of hydrogen peroxide.In order to improve the stability of hydrogen peroxide, factors such as light, heat, metal ion content and pH value must be controlled.The stable hydrogen peroxide has good stability due to its high purity and contains few impurities such as metal ions.