sodium bisulfate

What it is

Sodium bisulfate is a dry acid — listed as sodium bisulfate or sodium acid sulfate — used to lower pH. In pet food it acidifies kibble coatings to slow microbial growth, and in some cat formulas it helps manage urine pH.

Why it's in pet food

Acidity is a preservation lever: a lower pH makes life harder for bacteria on fat-coated kibble. In cat food it can also serve a urinary purpose — formulas targeting urine pH sometimes include it deliberately.

How Bowlmark scores it

Scores are deterministic math over the printed label — the rules below apply to every product identically, and nothing estimates or fills in a blank.

Sodium bisulfate carries no deduction on the additive pillar; the engine treats acidifiers as neutral processing aids. Preservative flags are reserved for BHA, BHT, and ethoxyquin.

Read the full methodology

Foods that list sodium bisulfate

Ranked by score where scores exist. Placement here is never sold.

• Purina Pro Plan Vital Systems Chicken & Egg Formula90
• Diamond Naturals Active Cat Chicken Meal & Rice Formula88
• Diamond Naturals Indoor Cat Chicken & Rice Formula87
• Purina ONE Plus High Protein Salmon & Ocean Whitefish Formula87
• Purina ONE Tender Selects Blend With Real Chicken87
• Purina ONE True Instinct Grain Free With Real Ocean Whitefish87
• Purina Pro Plan Adult Sensitive Skin & Stomach Salmon & Rice81
• Royal Canin Sensitive Digestion79

Sources

• ACVN — preservative systems in pet food
• MSD Veterinary Manual — feline lower urinary tract disease

Related ingredients

• potassium sorbate
• propionic acid
• rosemary extract
• sodium nitrite
• sorbic acid
• tbhq

Further reading

• Preservatives — natural vs synthetic, and what actually matters
• Storing pet food so it stays the food you bought