Food Preservation

Jul 14, 2023

It's peak season for fruits and vegetables from now through September: peppers, tomatoes, cucumbers, peaches, apricots, plums, berries … the list goes on and on.  It's not unusual for a neighbor to drop off a bag of peaches, or to find a roadside stand offering melons, or to encounter a box of cucumbers or zucchini labeled with a “free” sign when out on a walk.  Our farmers markets offer an amazing selection of locally-grown fruits and vegetables, and wild blackberries thrive on the banks of our creeks and rivers.  If you find yourself in the enviable position of having more fresh produce than you can possibly consume or give away, it's time to start canning and preserving. You'll be glad you did when you can pull out a jar of homemade bread & butter pickles at Thanksgiving, or slather your own apricot jam on a piece of toast come February.

Sun drying is the earliest form of food preservation. Evidence of this method has been found from 12,000 BC. Humans living in arid and semi-arid regions simply laid raw food in the sun to dry. This method is quick and easy for drying large quantities of fruits on drying trays after sulfuring.  Exposing halved fruits such as peaches and apricots to sulfur fumes for a period of time before drying prevents the browning reaction and preserves a fruit's bright color and quality.  The modern-day dehydrator works great for other foods and is especially useful for drying persimmons late in the fall when it's too cool for sun drying.

Apparently the ancient Greeks and Romans loved jams and jellies. Around 500 BC, traders began pulverizing over-ripe fruit, then boiling the juice and adding honey to turn what would have been waste into something useful. One of the first known cookbooks is De Re Coquinaria (“The Art of Cooking” in English), from the fourth century AD or earlier. It includes a recipe for jam which is simply fruit and sugar boiled together. Those living in northern climates with insufficient sunlight to properly dry fruits soon added this method to their food preservation techniques.

During the 15th century, curing became an effective means of preserving meat. While both ancient Egyptians and Romans used a salting method, it proved ineffective for storing meats. During the Middle Ages, it was discovered that storing meat inside a salt solution (brine) would lengthen the amount of time it took for the food to become spoiled. Placing meat in the brine prevented the growth of bacteria. This method was used by armies going to war, but the brined meat still didn't last long before going rancid. The meat offered little nutritional value and reliance upon it often led to scurvy. Because of the downsides of brining, the French emperor Napoleon spent time and money looking for a better way to preserve food for his armies. This interest would lead to the development of new methods such as canning and pasteurization.

Toward the end of the 18th century, natural refrigeration became a means of preservation in areas where snow and ice were available. Holes were dug into the ground and meat was stored and covered with snow during the winter. This method of preservation reduced both enzymes and bacteria, keeping meat from going rancid. But it wasn't until the invention of mechanical refrigeration that cold storage became more widespread.

The 19th century saw the introduction of mechanical refrigeration as well as methods of canning and pasteurization which added to the overall quality and safety of food preservation. Nicolus Appert, a French scientist, began sealing food in glass jars with cork, wire, and wax before placing them in boiling water. Appert discovered that this technique made the contents air-tight and kept out bacteria. But glass jars could also be cumbersome and would often explode due to pressure from the nonperishables packed into the jars.

At around this same time in England, there was increasing need to feed the navy as well as arctic explorers over long periods of time. Drying, pickling, or preserving in jars were the only methods of longer-term food preservation. Metal cans came into the picture when Peter Durand, a British merchant, patented a method of storing food in cans on behalf of French national Phillippe de Girard who had invented the method in 1811. Durand sold the patent to Bryan Donkin, a British inventor and manufacturer. Donkin began processing meat in iron tins, and this canned meat made its way to the English Royal household. Several days after King George III and Queen Charlotte tasted the canned meat, Donkin received a letter from the Duke of Kent telling him how much the King and Queen had enjoyed the meal. Soon the manufacturing company of Donkin, Hall, and Gamble began distributing canned foods to the British navy and eventually selling canned perishables throughout England and across the Atlantic to merchants in New York City.

Although canned goods could be purchased from England, it wasn't until an American, Gail Bordon, invented condensed milk in the 1850s that canned goods became commercially successful in the United States.

In the early years of the 20th century the United States Department of Agriculture (USDA) published its first guide to home food preservation. “Canning Vegetables in the Home” was published in the Farmer's Bulletin 359 in May 1909; a year later, “Canning Peaches on the Farm” appeared in the same publication.

Since that time, home canning has played a critical role in important eras of American history: growing and preserving one's own food helped many citizens supplement rationed food supplies during World Wars I and II; home canning was a means of survival for many families during the Great Depression of the 1930s; and the back-to-the-land movement of the 1960s and 1970s saw increased interest in preserving home-grown food. As many of us are well aware, a home canning resurgence occurred during the COVID pandemic, so much so that it became difficult to find canning jars for sale on grocery shelves.

The University of California Division of Agriculture and Natural Resources offers a Master Food Preserver Program in some counties (alas, not in Butte County; the closest program is in Yuba County).  The Program's website contains all the information you need to start canning safely – including plenty of useful recipes.

If you'd like to try some very easy ways to preserve the summer's bounty, here are two simple no-fuss recipes.

Fruit Leather: Any fruit or combination of fruits works well

 Wash fruit (peel stone fruits)

Puree three cups of your chosen fruit or fruit combination in a blender

Add a teaspoon of lemon or lime juice

Add a tablespoon of honey (optional)

Spread mixture on two baking sheets lined with parchment paper and either bake at 150 degrees or leave in the sun (covered with cheese cloth) until dry.

Bread & Butter Pickles:

 Mix together:  2/3 cup sugar

                        1 cup cider or white vinegar

                        1 teaspoon turmeric

                        2 teaspoons salt

                        1 teaspoon mustard seed        

                        1 teaspoon celery seed

Slice three to five cucumbers into rounds about 3/16ths of an inch thick and put into the mixture cold. Bring to a boil and boil for two minutes.  Pack into jars and seal (or just pack into jars, forego the canning process and store in refrigerator – super easy!).  Makes 2 pints.

UC Master Gardeners of Butte County are part of the University of California Cooperative Extension (UCCE) system.  To learn more about us and our upcoming events, and for help with gardening in our area visit our website.  If you have a gardening question or problem, email the Hotline at mgbutte@ucanr.edu or leave a phone message on our Hotline at 530-552-5812. To speak to a Master Gardener about a gardening issue, or to drop by the MG office during Hotline hours, see the most current information on our Ask Us section of our website.