A Brief Compendium of Techniques That Can Be Used for Food Preservation

Written by: Marge Vorndam, Master Gardener

Many gardeners are focused on preservation of the crops that they grew over the Summer.  Others are interested in extending the storage of other items such as meats, including fishes, for later consumption.  If you are a do-it-yourselfer, this missive will briefly introduce you to the various techniques that are in use to choose from for optimal outcomes. However, it is essential to further follow up on approaches that a preservationist may have interest.

The goal of food preservation is to prevent spoilage from microorganisms that would also love to participate in enjoying your food. There are many methods to choose from. Use our reference list and Google to find scientifically valid information on your chosen technique before proceeding in implementing any of these suggestions. The Reference section at the end can provide more detailed information and recipes.

Escherica coli – An example of a bacterial microbe enemy, E. coli, is pervasive in our environment and on our food.  Preserving methods disable microbes before they target our food, for example. E. coli and other microbes are responsible for a wealth of adverse health conditions in humans. This microbe is only one example of the host of organisms that will take advantage of our foods if they are not sufficiently sanitized. Photo source widely reproduced online.

• Freezing – This versatile method is likely used by many preservers already. Freezing keeps damaging microbes at bay, if not outright disabling them. Items that are popular for freezing are fresh fruit, blanched or cooked veggies, jams and jellies. Blanching before freezing helps to remove harmful organisms. Blanching is the process of briefly dipping the product into a boiling water bath to disable these organisms.
• Water bath canning – Warning! Water bath canning may be used to process high acid containing produce only! The acid content inhibits spoilage. Examples of these items are fruits, tomatoes, and jams. In some cases, lemon juice or vinegar can be used to increase acidity to the point that lower acidity produce can be water-bathed in a large canning pot set on a stove. Always check on the product that you are preserving re: using this method from a knowledgeable source.
• Pressure canning –High pressure must be used for produce, meats or pre-prepared foods that lack a high acid content. Water bath canning is not adequate to develop the high temperatures or pressure required to sterilize these foods. Pressure canning will require investment in appropriate equipment for this process to be used.

Fr. Boeckmann, C. 2024. An Introduction to Pressure Canning at home.
https://www.almanac.com/pressure-canning-guide

• Drying-Dehydration – Use a dehydrator or low temp Oven. Produce preserved in this way can be rehydrated later for cooking use. Dehydrating can be used when processing fruits, meats for jerky and herbs.  Once dried, these items can be jarred and stored for later use.  Even a warm room with air circulation and sunlight or a hot vehicle can be used.
• Pickling – Raw veggies are submerged in in an acidic brine. Vinegar or lemon juice is commonly used to aid the pickling process. Veggies that are pickled can be preserved by using water bath canning or refrigeration. Refrigerator pickles can be another way to pickle.  They slowly develop flavor from the brine over time in this cold environment. The pickling process generally results in a somewhat sour flavor.
• Smoking – This process is used with meats that are treated using salt or sugar and heavy dosing with a smoke stream, generally from wood products. The technique has a variety of approaches, but the overall point is to destroy the microorganisms that would otherwise spoil the meat.  Popular examples of foods resulting from the smoking process are bacon and sausage.
• Fermentation – Benefit: Probiotic development! Salt/saltwater brine is used, and fermentation occurs over weeks in an anaerobic (without air) environment.  Kimchi and sauerkraut production are examples of the use of this method. Lacto-fermentation is a subcategory where lactic acid bacteria are initially added to increase probiotic health.
• Root Cellars – These structures were popular historically long before refrigerators were on the scene. Digging underground holes or caves can enable storage of many hardier vegetables such as potatoes, pumpkins, and hard fruits like apples.  The benefit is that this frees up refrigerator and kitchen storage space.  Smoked meats can also be stored in this cool environment. Since underground locations provide a cooler environment, and since the entry is covered by some type of insulating material, items stored in this manner will last for several months.

Fr. Will, H. , nd. Build a root cellar on your farm.
FarmLife.  https://myfarmlife.com/home-garden/build-a-root-cellar-on-your-farm/

• Salting – Burying moist produce such as some fruits and meats in a quantity of salt is another way to preserve foodstuffs. Salt draws out excess moisture, which inhibits bacterial action. This is also a method that will hold items for long periods of time.
• Vacuum Sealing – This preservation method has gained in popularity in the relatively recent past. The process involves removing all air/oxygen from foodstuffs using a vacuum pump.  The product is placed in a specially constructed plastic bag that is sealed once the air has been removed.  Refrigeration/freezing of the sealed bag is recommended to further assure safe storage.

This list covers the majority of the methods available for preservation. Explore the methods further to choose an appropriate approach for your situation.

References

Hupping, C. 1990. Stocking Up: The Third Edition of America’s Classic Preserving Guide.   June 15, 1990

Bordessa, Kris. 2023. Pickling vs. Fermenting: What’s the Difference?
https://www.attainable-sustainable.net/pickling-vs-fermenting/

Bordessa, Kris. 2023. Home Food Preservation Methods for Saving the Flavor of Summer.
https://www.attainable-sustainable.net/food-preservation-methods/

Colorado State University Extension. Nutrition, Food Safety & Health.
This compendium provides specific in-depth information on the various topics discussed above. See for a comprehensive list, https://extension.colostate.edu/topic-areas/nutrition-food-safety-health/?target=publications