Low vs. High Acid Foods in Canning | Don’t Guess – Use This Chart

When it comes to canning, don’t rely on guesswork—foods with a pH of 4.6 or lower (high-acid) can be safely water bath canned, while low-acid foods (above 4.6) must be pressure canned to prevent botulism. Use the chart below to identify which is which, and always follow USDA-tested recipes for safety.

If you’re anything like me, you’ve probably wondered if you can just water bath a batch of beans or green beans and be done with it. I’m here to say, kindly but firmly—don’t. Canning safety comes down to one thing: acid level. And getting it wrong can mean serious health risks.

Let’s walk through how to tell the difference between low-acid and high-acid foods, why it matters, and exactly how to can each type safely.

Why pH Matters for Canning Safety

The main risk when canning at home is a bacterium called Clostridium botulinum, which thrives in low-acid, oxygen-free environments (like a sealed jar). This little menace can cause botulism, a rare but serious form of food poisoning.

According to USDA guidelines, safe pickling and canning rely on two things:

• Keeping the pH at or below 4.6 (acidic)
• Using enough heat to destroy dangerous bacteria

That’s why we use water bath canning for high-acid foods (like pickles, tomatoes with added acid, or jams), and pressure canning for low-acid ones (like meat, vegetables, or beans).

Use This Chart: Low vs. High Acid Foods

Here’s a handy chart to help you decide which canning method is required:

High Acid Foods	Low Acid Foods	Foods with Variable pH
Most Fruits	Asian pears	Tomatoes
Pickles	Figs	Tropical Fruits
Jellies & Jams	Papayas	Dates
Salsa & Sauces	Vegetables
Sauerkraut	Meat, Poultry & Seafood
Yogurt	Soups & Stock
Vinegar	Dairy Products

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Examples of High-Acid Foods (Safe for Water Bath Canning)

• Most fruits (peaches, pears, apples, berries)
• Tomatoes (with added lemon juice or citric acid)
• Jams, jellies, and fruit butters
• Vinegar-based pickles and relishes
• Applesauce and fruit juice

📌 If you’re making pickles, check out What Kind of Vinegar Is Best for Pickling? and Do You Have to Boil the Brine?

Examples of Low-Acid Foods (Must Be Pressure Canned)

• Meats and poultry
• Green beans, carrots, corn
• Peas, asparagus, potatoes
• Soups and stews (unless acidified)

If you’re unsure, always refer to a tested recipe from a trusted source like the USDA, Ball Blue Book, or your local extension office.

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A Note on Tomatoes

Tomatoes walk the line with a pH around 4.3–4.7, which means they must be acidified for water bath canning. Add:

• 2 Tbsp bottled lemon juice per quart (1 Tbsp for pints), or
• ½ tsp citric acid per quart (¼ tsp for pints)

This simple step keeps your tomatoes safe without needing a pressure canner.

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Final Thoughts from the Pantry

If you take nothing else from this article, remember this: low-acid = pressure canning, high-acid = water bath canning. It’s not just a preference—it’s a matter of safety.

I keep a copy of this chart on the inside of my cabinet door, right next to my jar rings. Trust me, once you get in the habit of checking pH and processing method, it’ll become second nature.

Thanks for stopping by, and happy (safe) canning!

Related reads:

• Pickling Safety 101 | Avoiding Botulism and Spoilage
• List of Canning Equipment I Actually Use

– Anne (aka Jelly Grandma)

👉 For a complete beginner-friendly guide, check out How to Pickle Just About Anything (Safely and Deliciously).