pH Adjustment Calculator

Calculate acid dose needed to reach a target pH for food preservation, using buffer capacity and acid type.

Current pH

Target pH

Batch volume (L)

Acid type

Buffer capacity (mol/L·pH)

Tab to move between fields

Acid needed (g)

1,325.63

Acid needed (kg)1.33

50% stock solution (mL)2,651.3

pH change2.3

Final acid conc. (%)1.33

Titratable acidity (meq/L)69

[A⁻]/[HA] at target pH11.75

H Current$0.00

H Target0

How to Use This Calculator

Enter the current pH and target pH of your food product.
Set the batch volume in liters, select the acid type, and enter the buffer capacity of the food matrix.
The calculator shows acid needed in grams and kg, 50% stock solution volume, pH change, final acid concentration, and Henderson-Hasselbalch conjugate ratio.
Add acid incrementally while stirring and verify pH with a calibrated meter before committing to the full calculated dose.
Acidified foods must reach pH ≤ 4.6 per FDA regulations for shelf-stable products.

How the result changes with Current pH

Current pH: Measured pH of the food product before acidification.
Target pH: Desired pH. FDA requires pH ≤ 4.6 for shelf-stable acidified foods.
Batch volume (L): Volume of the food product batch in liters.
Acid type: Select the acid type
Buffer capacity (mol/L·pH): Buffer capacity of the food matrix. Typical range 0.01–0.10 mol/L per pH unit. Higher for protein-rich foods.

Acid needed (g): Grams of pure acid required to achieve the target pH.
Acid needed (kg): Kilograms of pure acid for large batches.
50% stock solution (mL): Volume of 50% w/v acid stock solution needed.
pH change: Magnitude of pH reduction (current − target).
Final acid conc. (%): Weight/volume % of acid in the final product.
Titratable acidity (meq/L): Change in titratable acidity in milliequivalents per liter.
[A⁻]/[HA] at target pH: Henderson-Hasselbalch conjugate base to acid ratio at the target pH.

Identify Input Parameters
4 parameters
Current pH = 6.5, Target pH = 4.2, Batch volume (L) = 100, Acid type = 0 = 5 input(s) provided
Calculate Acid needed
Acid needed = molesAcidNeeded * mw
1325.63 = 1325.63
Calculate Acid needed
Acid needed = acidMassG / 1000
1.326 = 1.326
Calculate 50% stock solution
50% stock solution = (acidMassG / stockConcentrationGL) * 1000
2651.3 = 2651.3