How Can I Can Tuna? A Comprehensive Guide
Canning tuna at home allows you to enjoy delicious and nutritious seafood with control over ingredients and long-term storage, but it requires strict adherence to safety guidelines to prevent botulism. Here, we’ll detail the safe and effective way to preserve tuna using a pressure canner.
Why Can Your Own Tuna?
Canning tuna at home offers several advantages over purchasing commercially canned tuna.
- Control over Ingredients: You can choose your tuna species (albacore, yellowfin, etc.), select the oil (olive, avocado, or none), and control the salt content.
- Cost Savings: Depending on the price of fresh tuna in your area, home canning can potentially be more cost-effective, especially when buying in bulk.
- Sustainability: You can source tuna from sustainable fisheries, supporting responsible fishing practices.
- Improved Flavor: Many people find home-canned tuna to have a superior flavor to commercially canned products.
Understanding Botulism Risk
Botulism is a severe illness caused by a potent neurotoxin produced by the bacterium Clostridium botulinum. This bacterium thrives in low-oxygen environments like canned foods. Low-acid foods, such as tuna, are particularly susceptible. Therefore, proper pressure canning is crucial to achieve temperatures high enough to kill C. botulinum spores. Ignoring proper procedures can be life-threatening.
The Pressure Canning Process: A Step-by-Step Guide
Canning tuna safely requires using a pressure canner. A boiling water bath canner is not sufficient to reach the required temperature.
Gather Your Supplies:
- Fresh, high-quality tuna (about 1 pound per pint jar)
- Wide-mouth pint or half-pint canning jars (check for chips or cracks)
- New canning lids and rings
- Salt (optional, canning or kosher salt)
- Olive oil or avocado oil (optional)
- Pressure canner
- Jar lifter
- Lid wand (magnetic tool for lifting lids)
- Clean towels
Prepare the Tuna:
- Rinse tuna thoroughly under cold, running water.
- Remove skin, bones, and any dark flesh.
- Cut tuna into chunks or loins to fit into jars, leaving 1-inch headspace.
Pack the Jars:
- Sterilize jars by boiling them for 10 minutes. Keep them hot until ready to use.
- Place tuna pieces tightly in jars, leaving 1-inch headspace.
- Add salt (optional): 1/2 teaspoon per pint jar or 1/4 teaspoon per half-pint jar.
- Add oil (optional): 1-2 tablespoons per pint jar or 1 tablespoon per half-pint jar.
- Wipe jar rims clean with a damp cloth.
Apply Lids and Rings:
- Place a flat lid on each jar, centering it.
- Screw on the rings fingertip tight (not too tight).
Process in a Pressure Canner:
- Follow the manufacturer’s instructions for your specific pressure canner.
- Add the recommended amount of water to the canner (usually 2-3 inches).
- Place the jars in the canner on the rack.
- Secure the lid and bring the canner to the correct pressure.
- Process for the required time:
- Pint jars: 100 minutes at 11 pounds pressure (weighted gauge) or 11 pounds pressure at altitudes up to 2,000 feet (dial gauge). Increase pressure at higher altitudes (see table below).
- Half-pint jars: 100 minutes at 11 pounds pressure (weighted gauge) or 11 pounds pressure at altitudes up to 2,000 feet (dial gauge). Increase pressure at higher altitudes (see table below).
Altitude (Feet) Weighted Gauge Pressure (PSI) Dial Gauge Pressure (PSI) 0-1,000 11 11 1,001-2,000 11 11 2,001-4,000 15 12 4,001-6,000 15 13 6,001-8,000 15 14 8,001-10,000 15 15 Cooling and Testing Seals:
- Turn off the heat and allow the canner to cool naturally until the pressure returns to zero.
- Carefully remove the jars with a jar lifter and place them on a towel-lined surface.
- Let the jars cool completely (12-24 hours) undisturbed.
- Check the seals: The lid should be concave (curved downward). Press the center of the lid; it should not flex or pop.
Storage:
- Remove the rings (this prevents moisture buildup and rusting).
- Label the jars with the date and contents.
- Store in a cool, dark, and dry place for up to one year.
Common Mistakes and How to Avoid Them
- Inadequate Pressure: Not reaching the correct pressure can result in incomplete sterilization and botulism. Always follow your canner’s instructions carefully.
- Insufficient Processing Time: Processing for less than the recommended time will not kill C. botulinum spores. Adhere strictly to the recommended processing times.
- Overfilling Jars: Insufficient headspace can prevent a proper seal and lead to spoilage. Maintain the correct headspace.
- Reusing Lids: Canning lids are designed for single use. Reusing lids increases the risk of seal failure. Always use new lids.
- Not Adjusting for Altitude: Higher altitudes require increased pressure to achieve the same temperature. Use the altitude adjustment chart.
- Cooling the Canner Too Quickly: Rapid cooling can cause jars to break or seal improperly. Allow the canner to cool naturally.
Frequently Asked Questions (FAQs)
Can I Use a Boiling Water Bath Canner for Tuna?
No, absolutely not. A boiling water bath canner does not reach a high enough temperature to kill Clostridium botulinum spores in low-acid foods like tuna. Using a pressure canner is essential for safe canning.
What Kind of Tuna is Best for Canning?
Albacore tuna is a popular choice due to its mild flavor and firm texture. Yellowfin and skipjack tuna are also suitable options. Choose tuna that is fresh and of high quality.
Is It Necessary to Add Oil to the Tuna?
No, adding oil is optional. Some people prefer the flavor and texture of tuna canned in oil, while others prefer it without. If you choose to add oil, use a high-quality olive oil or avocado oil.
Can I Add Other Seasonings Besides Salt?
Yes, but be cautious. Adding too many ingredients can affect the canning process. Stick to dry herbs and spices in small amounts. Avoid adding acidic ingredients like lemon juice or vinegar unless you have a tested recipe.
How Do I Know If a Jar Has Sealed Properly?
A properly sealed jar will have a concave lid (curved downward). When you press the center of the lid, it should not flex or pop. If the lid is bulging or flexes, the jar is not sealed and should be refrigerated and used within a few days or reprocessed with a new lid.
What Should I Do If a Jar Doesn’t Seal?
If a jar doesn’t seal within 24 hours, you have two options: refrigerate the tuna and use it within a few days, or reprocess it with a new lid and following the canning instructions again.
How Long Will Home-Canned Tuna Last?
Home-canned tuna will last for up to one year when stored properly in a cool, dark, and dry place. After one year, the quality may start to decline, but it is generally still safe to eat if properly sealed.
What Does Botulism Look and Smell Like in Canned Food?
Unfortunately, botulism does not always have obvious signs in canned food. The food may look and smell normal. Never taste or consume food from a jar with a bulging lid, leaking contents, or any signs of spoilage. When in doubt, throw it out!
Can I Can Tuna in Different Size Jars?
Yes, you can use half-pint jars, but the processing time remains the same as pint jars. Always follow the recommended processing time for the largest jar size being used.
What if My Pressure Canner Doesn’t Have a Gauge?
Some older pressure canners use a weighted gauge. Ensure you understand how to properly use the weighted gauge and adjust for altitude as necessary. If you’re unsure, consult the manufacturer’s instructions or a local extension office.
Where Can I Find Reliable Canning Recipes and Information?
Consult the National Center for Home Food Preservation (NCHFP) website, your local county extension office, or the USDA Complete Guide to Home Canning for research-based recipes and guidelines.
Is it Safe to Can Tuna in a Dishwasher?
While some people use dishwashers to sterilize jars, it’s not recommended as a primary sterilization method for canning tuna. Boiling the jars for 10 minutes is a more reliable method to ensure they are properly sterilized before packing with tuna. Keep the jars hot until you are ready to use them.