A lot of us are trying to stretch our food budgets by growing our own or purchasing in bulk. Many are also joining CSAs (Community Supported Agriculture) programs, which provide them with produce (and sometimes other items) throughout the growing season. To take full advantage of local food sources, we need to find ways to store food after harvest. This post will give you a brief overview of different home food preservation methods, and direct you to addition resources. Then you can decide which methods works best for you.
Home Food Preservation – 10 Ways to Preserve Food at Home
There are many different methods of preserving fruits and vegetables. Some home food preservation methods are old, like cool storage, while others are new, like freeze drying. Many once common food storage methods are no longer recommended due to safety concerns. I use a mix of food preserving options. Each method gives a different flavor and texture, and it gives us more variety in our menus. Different fruits and vegetables also store better one way versus another.
1. Minimal Processing – Cool Storage and Room Temperature Storage
If you can make it work in your home, cool storage and room temperature storage are the easiest home food preservation options. This includes cool, dry storage, such as an unheated pantry or porch, and root cellaring, i.e., cool, damp storage.
“Root cellars” type storage areas may include:
- root cellars
- unheated basement space
- crawl space
- in ground “clamps” (holes or trenches for food storage)
- other options
Cool storage basics, including storage requirements for many crops, can be found in the post “Root Cellars 101” and “Above Ground Root Cellars – Enjoy Your Local Produce Longer“. Some good candidates for root cellar storage include:
My garden always includes storage crops that can store without much processing, such as: shell beans, pumpkins and squash and root vegetables. You can read more about my favorites in the post, “The 5 Easiest Vegetables to Store”.
Food preservation by drying is one of the oldest home food preservation methods. Food can be dried using:
- Commercial dehydrators, such as the Excalibur or American Harvest Dehydrator
- Solar dehydrators
- Sun Ovens
- Baking sheets in the oven
- Air drying/hang drying
Dried foods are great when storage space is tight, but not all foods dehydrate well. Store dehydrated foods in a cool, dry location in an airtight container for longest shelf life.
The USDA recommends pasteurizing dried foods at 160°F/71°C for 30 minutes or freezing at 0°F/-18°C for 48 hours to kill insects and their eggs, but I haven't had any insect problems with food dried in my commercial dehydrator.
Foods that may dehydrate well include:
- Fruit Leathers
Check out “Home Food Drying – 6 Things You Need to Know to Dehydrate Food at Home” for recommended dehydrating equipment, plus dehydrating guidelines and storage tips and a printable quick reference chart for fruit dehydrating. See Vegetable Dehydrating 101 for a printable list of vegetable blanching and drying times.
3. Canning – Water Bath Canning and Pressure Canning
Home canning is the heat processing of food in glass jars for preservation. For many years, food was heat processed in commercial facilities in cans (thus the term “canning” as opposed to “jarring”). The Mason jar was invented and patented in 1858, but didn’t see widespread use until later in the century.
Water bath canning can be done with any large stockpot or kettle with a lid, as long as you have a way to keep the jars from sitting directly on the bottom of the pot and can cover your jars with at least two inches of water. Water bath canning is used to preserve high acid foods (pH of 4.6 or lower), such as:
- Jams, jellies and other spreads
- Tomatoes (with added acid)
- Pickles and relishes
Can I use a pressure canner for water bath canning?
If you can a pressure canner, you may use it for water bath canning by leaving the vent open. If your canner has a rubber overpressure plug, that may also be removed.
Please be careful using a pressure canner for water bath canning. Some people have noted that they still get a slight pressure build up inside their older units, leading to a release of hot steam when the lid is opened. Loosely covering the canner with the lid (instead of locking it on) can help prevent steam buildup.
Read “How to Can Food at Home – Quick Guide to Safe Home Canning” for more information on water bath and pressure canning.
Pressure canning must be done in a pressure canner, which processes foods using high temperature, high pressure steam. A pressure canner is not the same as a pressure cooker, although some pressure canners can also be used for pressure cooking. Check with your owner’s manual.
PRESSURE CANNING MUST BE USED FOR LOW ACID FOODS, such as:
Unsafe canning practices can lead to botulism poisoning, but it's easily avoided with simple safety steps. See “Botulism – Causes, Symptoms, Treatment, Tips for Safe Home Canning“.
Freezing foods typically produces flavors and textures most similar to fresh, and can be done without much specialized equipment. It is recommended that you blanch or cook most vegetables before freezing to stop enzyme action and insure best quality.
What is blanching? Blanching involves heat treating the veggies, then immersing them in cold water to stop the cooking process. Three minutes in boiling water is a common blanching time.
Fruits are frozen “as is”, or with sugars or antioxidants to extend storage life and slow discoloration. With both fruit and vegetable preservation, I like to initially freeze them on a cookie sheet and then pack them into vacuum sealed packages for long term storage.
Sealing frozen produce in vacuum seal bags helps prevent ice crystal formation and can extend the storage life of frozen foods 3 to 5 times longer. I rarely store anything in the freeze without vacuum sealing.
5. Freeze Drying
Freeze drying (lyophilization) is now an option for home food preservation. The company Harvest Right manufactures home freeze drying units in Utah.
How does a home freeze dryer work? From “Home Freeze Drying – The Good, The Bad and The Ugly”:
- First, you get a heavy duty freezer (the Harvest Right units drop to -30°F (-34°C) or colder).
- Second, you pair this up with a completely airtight chamber that can hold a vacuum (no oxygen) every single time you use it.
- Third, you tie in a high end vacuum pump strong enough to suck the stripes off a zebra.
- Fourth, you add a heater and thermostat, so you can cycle the temps up and down, repeating the sublimation process for hours on end.
- Fifth, tie in a humidity sensor to make sure the water is out, triggering the cycle completion.
Home freeze drying allows you to preserve many foods that do not store well using other methods, such as dairy products, full meals (hot dishes, cream based soups, etc), and leftovers. You can also store vegetables, fruits, meats and seafood. For a detailed review and more information, see “Harvest Right Home Freeze Dryer Review”. You can also read a comparison of freeze drying and dehydrating.
Natural fermentation can be used to change low acid foods into high acid foods, giving them a longer shelf life to store “as is”, or allowing them to be canned in a water bath canner instead of a pressure canner. (Remember, water bath canning is suited for high acid foods.)
Through the use of salt, whey or specific starter cultures, food is fermented. This improves its digestibility and nutrient content. It becomes what is referred to as a “live culture food”.
Because fermentation involves substances such as lactic acid and specific microbes, the flavor profile and texture of the food does change. Fermentation is responsible for treats such as chocolate, cheese, yogurt, and kombucha, as well as pantry staples like sauerkraut, kimchi, sourdough bread and vinegar.
For detailed instructions on creating your own live culture foods, see The Complete Idiot’s Guide to Fermenting, or click here to download this free fermenting formulas cheat sheet from Traditional Cooking School by GNOWFGLINS.
7. Preserving in Salt and Sugar
Preserving foods in salt and sugar was more common before modern canning, freezing and dehydrating were available.
Salt and sugar draw liquid out of the food. (They are hydrophilic.) This interferes with microbe growth. Bacteria and molds need water to grow, just like us. These methods significantly impact food texture and flavor, so they have become less common.
Herb infused salts and sugars are a fun way to easily preserve your fresh herbs. Visit “Lavender – How to Grow It and Use It for Food, Medicine and More” to learn how to make a basic herbal sugar.
8. Immersion in alcohol
Like salt and sugar, alcohol draws water out of food, inhibiting microbe growth. You can submerge small amounts of food completely in the hard liquor of your choice, and they will store almost indefinitely. Don’t try to preserve too much food in too little alcohol. There’s a limit to how much water can be absorbed.
This food preservation method is best for making flavor extracts and preserving high acid foods such as fruit. Remember, low pH also inhibits mold and harmful bacteria growth.
- Liquid Sweetener from Homegrown Stevia
- Homemade Extracts – Vanilla, Lemon and Almond
- How to Make Chocolate Mint Extract
9. Vinegar Pickling
Microbes can't survive in a high acid environment, so vinegar can be used for food preservation without heating/canning. Think old-fashioned pickle barrel. I make at least one batch of vinegar pickles every season.
10. Immersion in Olive Oil
This home food preservation method is very common is some parts of Europe, but it is not one I recommend for the inexperienced home food preserver. Food is immersed in oil, locking out the air, to preserve it. The problem is that if the vegetables are low in acid, they present a serious botulism risk.
For safe instructions on how to make herb infused oils, see “How to Infuse Herbs in Oil, Water, Vinegar, Alcohol or Honey”.
Which Food Preservation Method is the Best?
It really depends on what you're trying to store and your storage conditions.
The Case for Canning
“While some nutrients are lost during canning, recent research has shown that refrigerating fresh fruits and vegetables also results in nutrient losses, especially of fragile vitamins like vitamin C. For example, broccoli loses 50 percent of its vitamin C and Vitamin A (in the form of beta carotene) after five days of refrigeration, similar in scale to the loss of vitamin C during cooking and canning. This is because plant foods are alive and thus continue to metabolize nutrients during storage.
It's safe to assume that root cellar storage causes the same magnitude of nutrient loss. Frozen food loses more nutrients than canned food after six months of storage. Dried food loses the most nutrients. With this in mind, canning is preferably done very soon after harvest, when nutrients are at their peak, thus preserving the most nutrients possible. “
The Case for Dehydrating
In contrast, Mary Bell's Complete Dehydrator Cookbook states:
When you dry foods at home under gentle conditions, you produce a high quality product. Compared with canning and freezing, both of which involve extreme temperatures, food drying is the least damaging form of food preservation.
The Case for Freeze Drying
The article “Freeze-drying fruit is top technique for retaining nutrients: Study” on Foodnavigator.com notes:
“Research conducted by Sheffield Hallam University found that freeze-drying strawberries resulted in zero loss of vitamin C and phenolic content an minimal losses in total antioxidant capacity (TAC) – only 8%. In contrast, fresh strawberries chilled for equal time showed a vitamin C loss of 18%, a TAC loss of 23% and a massive 82% loss in phenolic content.”
In terms of taste and texture, I generally prefer frozen, canned and freeze dried products. Fermentation adds nutrition, but fermented foods generally store for less than a year. Weeks or months of storage is more common. Dried foods can last for years and take up very small amounts of space. They are best used in soups, stews or other recipes where they will benefit from long, slow cooking with plenty of liquid, or as snack foods.
Freezing is probably easiest for the beginner with minimal equipment, but requires freeze space, which can be limited. Canning can be used on a variety of foods, but does require some basic equipment. Canned goods are best used within 1-2 years. No matter which home food preservation method you choose, properly ripened produce picked and processed quickly is likely nutritionally superior to most grocery store offerings.
Recommended Food Storage Resources
I hope you find this post useful. Please consider sharing it if you do, and let me know if you have any home food preservation questions that you'd like answered.
Originally posted in 2012, updated in 2017.