What is the Difference Between High-acid and Low-acid Processing?
The FDA CFR113 defines low-acid foods (other than alcoholic beverages) as having a finished equilibrium pH greater than 4.6 and a water activity (aw) greater than .85. For example, tomato products having a finished equilibrium pH less than 4.7 are not classified as low-acid foods. The division between low-acid and high-acid foods is based on the limited pH growth of clostridium botulinim.
- High-acid products have a pH lower than 4.6
- Low-acid products have a pH level higher than 4.6