The Science of Home Food Storage: Yes, It Matters | house style

Have you ever wondered why it’s so important to only use research-based recipes in home canning? Participants in Penn State Extension home canning classes frequently tell educators that they have canned a family or friend’s favorite recipes, recipes found somewhere online, in various cookbooks. cooking or inventing their own recipes. This article will explain why these recipe sources are not safe by outlining the food safety science behind research-based home canning recipes and show how you can use or adapt your favorite recipes for safe home canning. .

The research-based safe canning recipes that Extension can recommend have been tested in an Extension University or United States of Agriculture laboratory. During testing, researchers standardize the recipe, including measurements of all ingredients, jar sizes, pH, time, temperature, and pressure measurements. Other factors that food scientists measure for safe canning recipes are water activity (the amount of water in food), heat penetration into the jar, thickness of the food product, size of food pieces, raw and hot packing methods, canning at various altitudes and amount of head space (measurement of the distance between the food and the rim of the jar ). These factors interact to affect the final temperature and time it takes inside the jar to reach the levels needed to kill pathogenic bacteria (causing foodborne illness) and bacterial spores.

Cooking temperatures of 180 to 212 degrees F destroy most bacteria, molds and yeasts that can cause spoilage and possible foodborne illness. These temperatures will also inactivate enzymes in foods that negatively alter color, texture, flavor and nutritional value. However, to kill bacterial spores, such as the potentially deadly Clostridium botulinum, canned low-acid foods (pH > 4.6) such as most vegetables (except pickled or acidified tomatoes), meats and poultry, and combinations with these foods, must reach 240 degrees F. The only way to raise the temperature to 240 degrees F or higher is under pressure.

This search for safe home canning recipes can only be conducted in a laboratory with special equipment and trained food scientists. However, how can you safely bring back one of your unresearched recipes? Find a USDA or University Extension recipe that is very similar and use it. For example, many people have a family favorite spaghetti sauce recipe. Penn State Extension’s “Let’s Preserve Tomatoes” has several spaghetti sauce recipes, so find one that’s similar. Then, if you have other ingredients in your recipe that aren’t in the research-tested recipe, add them only when you’re ready to cook and serve the spaghetti sauce, such as added vegetables or herbs. Note that you cannot modify a research-tested home food preservation recipe unless it specifically states so. The exception is for salt; you can change the amount as it is not used for preservation, just for taste.

So, now you know a little more about the science behind safe home canning and using research-tested recipes that will help keep you and your family safe. To learn more about safe home canning procedures and recipes, visit the Penn State Extension website and “Let’s Preserve” series at .

Upcoming webinars, events

Penn State Extension is pleased to continue to provide quality education through a wide variety of webinars and recordings. If you are having difficulty registering online for one of these live webinars, please contact the Penn State Extension customer service team at 877-345-0691. Most of these webinars will be recorded and can also be viewed later. Keep searching our website: for the latest offers.

Herbs from the garden to the kitchen, an informal workshop with the herb experts from the Master Gardeners, Saturday, April 23, 9:30-11:30 a.m. at the Ag Heritage Center, 185 Franklin Farm Lane, Lower Level Meeting Room 7/8. This class is currently full; you can visit for more information and to be added to the waiting list in case of cancellation. Participants will learn about different types of herbs, including when and how to harvest them from the garden to use in culinary dishes, how to include herbs in the landscape, and how to conserve them.

The garden hotline begins for the season on Monday, April 25 and will run until September 30. Master Gardeners will be available at the Extension Office, 181 Franklin Farm Lane, to help you with your vegetable garden questions on Mondays, Tuesdays and Thursdays from 10 a.m. to 1 p.m. pm except on holidays when the office is closed (Memorial Day, Independence Day and Labor Day). Call 717-263-9226, email [email protected], or stop by the extension office for help with your garden problems. You can bring plant and insect samples for identification, diagnosis and recommendations.

Master gardener Selling plants 9 a.m. to 1 p.m. Saturday, May 21, located along the creek at the Extension Office and Ag Heritage Center, 181-185 Franklin Farm Lane. The Master Gardeners are delighted to welcome the Plant Sale back after a two-year hiatus and to share their gardening expertise with Plant Sale customers. Plants available at very reasonable prices include greenhouse-grown annual flowers, herbs, tomatoes, peppers and other vegetables, including old and unusual varieties, as well as perennials, ground covers, shrubs and trees. New this year, ‘plug’ plants, small perennials good for mass planting and drifting, will be available, including great late season bloomers for pollinators. Also new this year, we will accept Visa and MasterCard credit and debit cards, as well as cash and checks, for payment. Proceeds from plant sales support Master Gardener’s educational activities in Franklin County. Bring your gardening questions and get plant and planting information from friendly, knowledgeable Penn State Master Gardener volunteers.

Submitted by Lynn James, MS, RDN, LDN, Senior Extension Educator for Penn State Extension Franklin County. Source: Andress, EL and Harrison, JA (2014). So easy to store. University of Georgia Cooperative Extension.