N-Preserb is used to substitute Sodium Benzoate and Potassium Sorbate. N-Preferb is fit for acidic foods such as soy sauce,fish sauce,fruit & vegetable pickles. It is synthetic which has property in control acid & alkaline ph. In other words, it can control the growth of all bacteria . And due to Benzoic acid Free, this product can export to many countries which ban Benzoic acid. . N-Preserb can extend the shelf life according to the type of packaging, products and storage. And the suitable pH is 5-6.