ε-Polylysine Hydrochloride Manufacturer,Food Additives Quote

The stability of ε-polylysine hydrochloride at different pH values is an important factor to consider for its application in fields such as food and cosmetics. Below is a detailed study of its stability:

Ⅰ.Effect of pH on the Stability of ε-Polylysine Hydrochloride

1. Optimal pH Range:

ε-Polylysine Hydrochloride exhibits high stability within the pH range of 4.0 to 7.5, with its relative antimicrobial activity remaining above 95%. This indicates that, within this pH range, ε-polylysine hydrochloride effectively exerts its preservative effect and inhibits microbial growth.

2. Stability at High pH:

When the pH increases to the range of 8.0 to 9.0, the relative antimicrobial activity of ε-polylysine hydrochloride decreases by about 15%. This suggests that, at high pH values, the preservative effect of ε-polylysine hydrochloride may be somewhat compromised.

Ⅱ.Other Factors Affecting the Stability of ε-Polylysine Hydrochloride

In addition to pH, other factors can also affect the stability of ε-polylysine hydrochloride, such as temperature and salt ion concentration.

1. Temperature:

ε-Polylysine hydrochloride demonstrates excellent heat stability. Even when treated at 121°C for 60 minutes, its stability remains high. However, prolonged exposure to high temperatures may have some impact on its activity. Therefore, it is important to control the heating time and temperature during practical applications.

2. Salt Ion Concentration:

Different salt ions affect the stability of ε-polylysine hydrochloride in varying degrees. For example, Na+, NH4+, Mg2+, and other salt ions have no significant effect on its relative antimicrobial activity. However, metal ions such as Ag+, Fe2+, and Cu2+ can inhibit its antimicrobial activity when their concentration exceeds 0.8 mol/L. This is likely due to these metal ions binding with ε-polylysine hydrochloride, reducing its activity.

Ⅲ.Methods to Improve the Stability of ε-Polylysine Hydrochloride

To enhance the stability of ε-polylysine hydrochloride under various conditions, the following methods can be applied:

1. Optimize pH:

When using ε-polylysine hydrochloride, it is recommended to apply it in a pH range of 4.0 to 7.5 to fully exert its preservative effect.

2. Control Temperature and Salt Ion Concentration:

 In practical applications, it is important to control heating time and temperature to avoid prolonged high-temperature treatment. Additionally, care should be taken to avoid contact with metal ions such as Ag+, Fe2+, and Cu2+, as they may reduce its activity.

3. Choose Appropriate Packaging Materials:

Selecting the right packaging materials can protect ε-polylysine hydrochloride from adverse factors such as light, heat, and moisture, thereby improving its stability.

ε-Polylysine hydrochloride shows high stability within the pH range of 4.0 to 7.5 and can effectively exert its preservative effects. However, its activity may be affected in high pH environments. To improve the stability of ε-polylysine hydrochloride, it is important to optimize pH, control temperature and salt ion concentration, and choose appropriate packaging materials. These measures will help extend the shelf life of food and improve food safety.