Canning Basics

Each year during canning season I have so many requests from my friends to either teach them to can or to make a video (haha... no) on how to can. I can almost everything- jams, jellies, fruits, tomatoes and salsa, pasta sauce, tuna, and vegetables- and I have been canning pretty much my whole life. I think I have made every mistake there is to make, seen every disaster that could happen, and have had to throw out whole batches because of "mess ups". Canning is not difficult, but has to be done properly and per guidelines to keep it safe.

This blog post is just the basics for beginners to learn what to do and not to do when canning. If you follow the basic rules, you'll have great outcomes each time. 

1. There is a difference between waterbath canning and pressure canning. Before canning anything in a waterbath, read my blog post on Waterbath vs. Pressure Canning here. 

2. Make sure you use new lids each time. Jar rings can be reused over and over again until they are rusty or bent, but new lids must be used or a proper seal wil not form. 

3. Prior to sealing any food, you should sterilize your jars by running them through the dishwasher. If you don't have a dishwasher, wash them in hot, soapy water and rinse with hot water. 

4. Lids and rings should also be sterilized. You cannot put lids in the dishwasher. I clean mine by boiling them for 2 minutes. 

5. "Headspace" means the space on the top of the jar between the product and the lid. Recipes will specify a headspace. Pay close attention and follow the instructions. Leaving too little headspace can prevent sealing or cause product to "escape" or leak out during processing. 

6. Learn to adjust for elevation. When using a pressure canner, most recipes will say something like "Process at 10 psi for 10 minutes". The higher your elevation, the higher the pressure must be. The FDA has a handy website with these instructions. 

7. Get a pH meter and use it. It's important to know what the pH is on certain foods to determine whether you can use waterbath processing or not. 

8. When measuring pH, keep in mind that you are measuring all of the contents of a jar. So, if you are canning tomatoes, but you add onions, peppers, and spices, the pH will change from that of just tomatoes. Remember, 4.6 or lower, waterbath is ok. 4.7 or higher, only pressure canning is safe. The FDA has a guideline chart if you need some help. Before canning, please read my post on safe pH levels here. 

9. Follow the FDA and canning guidelines always.

10. If a recipe uses vinegar or lemon juice, use the specified amount. Do not skimp. Vinegar and lemon juice are used to make jars acidic to kill harmful bacteria and botulism spores. If not prepared correctly, waterbath canning will not kill botulism spores, which can be harmful. 

11. Always label your jars with the name of what it is, the date you canned it, and a batch number. Batch numbers come in handy. If I make two separate batches of dill green beans, both in July 2016, and one batch was too salty or bitter, I know which cans to throw out and which to save. Similarly, if I make one really kick ass batch of salsa, I know why, and I know I can recreate it. Batch numbers rule. 

12. Store jars in cool, dark places. I keep mine in my food pantry. Basements are a popular storage space. Keep out of sunlight, which can heat and brown fruits. My grandmother had some jars in her laundry room, and because of the heat, several seals popped. It was a huge mess to clean and a shame of a waste.

13. Wear an apron. Don't ruin your clothes.

14. Wear clothes toed shoes. Trust me. A hot, heavy jar is not friends with your feet. Ouch.