Food Safety Feature Articles
Remember to keep tomatoes safe if freezing or canning
Gardens are beginning to produce an abundance of tomatoes. That means the dilemma of how to preserve the tomatoes has begun. Vine-ripened, disease-free, firm tomatoes are the best for preserving.
“Tomatoes can be frozen or canned following proper procedures. Safety is the key. It is not safe to open kettle or oven can tomatoes” said Tammy Roberts, nutrition and health education specialist, University of Missouri Extension.
Freezing tomatoes is easy according to Roberts.
Just wash and dip them in boiling water for 30 seconds. Peel and core, and freeze whole or in pieces. Roberts also recommends packing the tomatoes into a container, leaving one inch of headspace, and then seal and freeze.
“It is best to use frozen tomatoes for cooking because they will not be solid when thawed. I put frozen tomatoes in crock pot soups, stews and chili,” said Roberts.
Unlike most vegetables, tomatoes can be safely water-bath canned because of their higher acidity, but you will need additional acid to keep microorganisms at bay. This is true even of heirloom tomatoes.
“Gardeners have been asking if heirloom tomatoes are acidic enough to be canned without added acid,” Roberts said. “University horticulture researchers have concluded the pH of heirloom plants is no different from the non-heirloom varieties, so the same recommendations apply for acidifying.”
To add acid, Roberts recommends using two tablespoons of bottled lemon juice or one-half teaspoon of citric acid per quart.
Be sure to use only firm, ripe tomatoes for canning. Tomatoes that are overripe, soft, moldy or picked from dead vines may not be acidic enough.
The next step in the process is to wash and dip tomatoes in boiling water for 30 to 60 seconds or until skins spilt. Then dip them in cold water, peel skins and leave them whole or half.
Add bottled lemon juice or citric acid to quart jars and leave one-half inch head space. Process quarts in a water bath for 50 minutes or pressure can for 25 minutes at 11 pounds of pressure.
Publications featuring research-based recipes for preserving a variety of foods are available from MU Extension at http://extension.missouri.edu.
 |
Site Administrator: |
|
|
|
Last update: Monday, August 01, 2011
