When it comes to home-grown fruit and vegetables, too much of a good thing certainly is a good thing – if you know how to preserve the abundance.
There are several options for preserving home-grown crops, including freezing, dehydrating and canning. All have benefits and challenges, but the rewards of enjoying your hard work all year are certainly worth the effort to preserve them correctly.
The most important thing to remember about preserving is to use a reliable, updated source of information. Grandma’s old recipe for putting-up tomatoes may sound wonderful, but it might not meet today’s standards for safety. One of the best sources of information is the National Center for Home Food Preservation. You will find good recipes and safety tips on the center’s website at http://nchfp.uga.edu.
Another great source for home preserving is the Master Food Preservers program sponsored by the Cooperative Extension, University of California, Sacramento County. The Master Food Preservers offer public classes to teach the art and science of preserving food safely at home. Check the preservers’ website for a list of upcoming classes at http://cesacramento.ucdavis.edu/.
Preserving is a lot of work so make sure you begin with the best quality fruit and vegetables. Food should be fully ripe, but not over ripe. Also make sure everything that comes in contact with food, such as utensils and kitchen towels, is clean. Follow recipes exactly. This is especially important when canning. Adding or changing ingredients can affect the safety of the end product. Here are some other guidelines:
If you’ve got the freezer space, freezing is the easiest way to preserve what you grow. Not all foods, however, are suitable for freezing. Some vegetables, such as cucumbers, summer squash and greens, turn mushy. Some fruit, such as pears or berries, change color and texture. That doesn’t mean freezing isn’t safe, it just means that, for some items, you should expect some changes in texture. Prepping foods correctly for freezing will give you better success.
Use the correct containers. Rigid containers, such as plastic bowls with snap lids, should be moisture proof and have a tight seal. Heavy-duty plastic bags (those made for freezing) are fine as long as they can be sealed tightly. If you use plastic bags gently press the bags to remove as much air as possible before sealing.
Liquids expand when frozen. When freezing liquids or foods prepared in sauce, leave about 1 inch of air space at the top of the container. If packed too tightly, the container might pop open in the freezer.
Most vegetables hold up better if they are blanched in boiling water before freezing. Hard vegetables such as carrots should be blanched about five minutes. More delicate vegetables, such as broccoli flowerets, take just a minute or two. Blanching prevents flavor loss and helps preserve color, texture and nutrients. Cool vegetables quickly after blanching by plunging them into cold water to stop the cooking. Drain thoroughly before packing and freezing.
Fruit should be washed and sorted before freezing. While it is not necessary to freeze fruit with a sprinkle of sugar or packed in sugar syrup, sugar does help retain flavor and texture.
Fruit that tends to darken when exposed to air, such as apples, peaches, apricots and pears, should be treated with ascorbic acid or a commercial fruit color preserver. Fruit that has darkened is safe, it’s just prettier if treated.
Freeze in small quantities or in amounts that you will use at one time. For example, if your favorite zucchini bread recipe calls for 2 cups of grated zucchini, freeze it in 2-cup portions.
Frozen food should be kept at 0 degrees and thawed in the refrigerator or the microwave oven.
Frozen fruit and vegetables should be used within a year. They will still be safe to eat after that, but the quality won’t be as good.
If the power goes out or the freezer stops working, don’t open the door. If the freezer is full, food should stay frozen for two days. Vegetables and fruit can be refrozen if ice crystals are still present or if the freezer stayed at 40 degrees or lower. Discard any thawed foods that have reached room temperature or show signs of spoilage.
A benefit to drying is that food is easy to store and takes up less storage space. The basic premise behind dehydrating is that bacteria, molds and yeasts which spoil food cannot live in the absence of water. So as long as dried foods are kept dry, they won’t spoil.
The easiest way to dry fruit and vegetables is with a food dehydrator. Dehydrators are small table-top appliances with mesh racks for holding pieces of food. Most work by circulating air heated to 140 degrees around the trays. If you use an electric dehydrator, follow the instructions that come with it for dehydrating.
It is possible to dehydrate some foods in the sun or a convection oven. If you use a convection oven, it needs to be set at 140 degrees or at the lowest temperature possible and the door left ajar. Here are some basic guidelines for dehydrating:
Fruit that tends to turn dark when exposed to air should be pretreated with ascorbic acid. You can also use a sulfite dip, but many people are sensitive to sulfites. In most cases ascorbic acid is the best choice even though the protection might not last as long as with sulfites.
Pure ascorbic acid is available in tablet or powdered form at grocery stores and some pharmacies. You can also use fruit juice that is high in vitamin C, such as citrus or pineapple, but juice is not as effective as pure ascorbic acid and it adds flavor to the fruit.
Place fruit pieces in a single layer on drying trays and leave space for air circulation. You can spray trays with nonstick cooking spray to prevent sticking.
Fruit is safe for sun drying, especially in the Sacramento area where humidity is low. Experts do not recommend vegetables for sun drying because of the low sugar content.
Outdoor drying is best done when the temperature is 85 degrees or higher. Plan to move the racks indoors at night or if there is a chance of rain.
Make sure the screens you use are safe for contact with food. Old window screens won’t work. Use stainless steel, fiberglass or plastic.
Cover food with cheesecloth or another screen to protect it from insects and birds.
Dried fruits should be leathery and pliable when finished drying. Squeeze several pieces together in your hand. If they don’t stick together when released, they are done.
Store dehydrated fruit in airtight containers in a cool, dry, dark place for up to a year. They will be safe to use after longer storage, but the quality won’t be as good.
Canning is a labor-intensive but rewarding way to preserve the bounty from the garden. The process involves quickly heating jars of food to high temperatures in order to preserve color and flavor while destroying spoilage organisms. As food inside the jars cools, it shrinks and forms a vacuum inside the jar, which seals the lid to the jar.
There are two types of canning, water-bath and pressure canning. The method you use depends on the type of food you are preserving.
High acid foods, such as fruit, tomatoes, jams and jellies, can be safely preserved with a water-bath method. Water-bath involves submerging filled jars in a kettle of boiling water for a certain amount of time. Low acid foods, such as beans or squash, must be processed in a pressure canner, which reaches higher temperatures than water-bath. If you use a pressure canner, follow its instructions.
Follow recipes and guidelines from an updated, reliable source such as the USDA or Master Food Preservers.
Making even minor changes in a recipe, such as reducing the acid or adding extra ingredients can change the processing time or method, so measure carefully and don’t be tempted to alter recipes.
Use the proper equipment. Reusing old jars, as long as they are not cracked or chipped, is fine. Reusing old rings in good condition is OK too, but always use new lids.
Use only Mason jars made for home canning, not regular glass jars, such as mayonnaise jars, because they will break and lids might not fit tightly.
After filling jars and before you adjust the lids, wipe the top with a clean, damp cloth to remove any spilled food or liquid which might prevent a tight seal.
Make sure you follow the correct processing time and technique for the type of food you are canning.
If a jar does not seal correctly, refrigerate it and plan to use it within a few days or freeze the contents.
Before using home-canned foods, check the food for mold, off odors and broken seals. If food spurts liquid when the jar is opened, discard it.
Store home-canned food in a dark, dry place and plan to use it within a year for best quality.
Sources: National Center for Home Food Preservation, http://nchfp.uga.edu; “So Easy To Preserve,” 5th edition, The University of Georgia Cooperative Extension; “Complete Guide to Home Canning,” USDA, National Institute of Food and Agriculture; Master Food Preservers, University of California Cooperative Extension, Sacramento County, http://cesacramento.ucanr.edu/Master_Food_Preservers_181.