As East Texans begin to harvest the abundant fruit and vegetables of summer, the Extension office receives many questions about food preservation — especially canning. There is a long tradition of canning backyard bounty to provide wholesome, nutritious foods throughout the year. Unlike our grandparents, most of us no longer need to can to ensure survival. Rather, it’s done for the enjoyment, quality time with loved ones and, of course, the delicious end product.
No matter one’s reasons for preserving food, it is important to follow standard, tested procedures to ensure safety and quality. Unfortunately, there is much misinformation about canning that leads to food waste, illness or worse.
Plenty of people use food preservation techniques that are not endorsed by a reliable source. They may say that it’s always been done that way and no one ever got sick. If that is the case, they have truly been lucky. Extension recommends only using research-based methods to minimize risk of food-borne illness. Botulism is no joke, and mold and other pathogens in your canned goods are no fun either.
Here are a few tips for safe canning at home:
Start with a clean preparation area and the freshest foods possible. Check jars for nicks and cracks. Make sure your equipment is clean and in good working order.
Always use a pressure canner when canning low-acid foods. This includes most vegetables (except many tomato products), seafood, poultry and meat. If using a pressure canner with a dial gauge, have it tested each year.
Always use tested recipes that have up-to-date, researched processing (canning) times. Reliable sources include USDA and Extension publications, manufacturers of canning equipment and the National Center for Home Food Preservation (http://nchfp.uga.edu/).
Do not alter ingredients in tested recipes, which can change the acidity and make the product unsafe. If you want extra onion in your salsa, just add it when serving, not before processing.
When filling jars, always use the correct headspace. Having too little or too much headspace can affect how the lid seals and the quality of the final product.
Avoid unsafe techniques, such as open kettle, steam or oven canning.
Open kettle canning involves heating the food to boiling, pouring it into the jars, applying lids and allowing the heat of the jar to cause the lid to seal. With this “how Granny always did it” method, the food is not heated adequately to destroy the spoilage organisms that can enter while filling the jar. It also does not produce a strong seal. This method is not safe! Processing jars in a boiling water bath or in a pressure canner drives air out of the jar and produces a strong vacuum seal.
Oven canning. Occasionally people ask about processing jars in the oven. They claim a friend or neighbor promotes it as a simple method of canning. What they fail to understand is that oven heat is not the same as heat from a boiling water bath or from steam in a pressure canner.
First of all, jars are not designed to withstand oven temperatures and can break or even explode, causing injury from broken glass.
Secondly, dry heat is not comparable to the moist heat of a boiling water bath. Processing in an oven will not heat the contents in the coldest part of the jar in the same way as boiling water.
Thirdly, oven heat will not increase the temperature inside the jar above boiling to be adequate to destroy botulism spores in low-acid foods. Only in the enclosed conditions of a sealed pressure canner will you be able to increase the internal temperature to 240 F. Oven canning is not recommended!
Canning the summer bounty can be a fun and rewarding experience. It’s important for people to have confidence to do it safely and effectively. The Texas A&M AgriLife Extension Service in Angelina County will be hosting hands-on canning workshops on Monday, June 20, and July 18 at 6:30 p.m. At time of writing, location and additional details TBD. To participate or for more info, visit http://angelina.agrilife.org/events/ or call (936) 634-6414.