The Many Options for Preserving Foods
There are many options for preserving foods, each with its own benefits and downsides. Here are some things to consider, depending on which method you choose.
1. Canning
Canning can be a cost–effective way to preserve the quality and extend the shelf–life of fresh foods at home. Foods which are commonly canned include applesauce, vegetables, jams and jellies, and baby food purees.
The basic steps for proper canning include thoroughly washing the fresh produce you’ll be using (with cool tap water, never soap or bleach), peeling and hot–packing if needed, adding acids like lemon juice or vinegar if the food isn’t already sufficiently acidic, and using self–sealing containers with lids.
Canning jars are then processed in boiling water (for acidic fruits and vegetables) or by using a pressure canner (for low–acid fruits and vegetables) for a specific amount of time. This kills any pathogens and prevents bacterial growth to ensure food safety.
Home canning can offer significant financial savings, and has no risk of bisphenol–A (BPA) or phthalates contamination, as canning uses glass mason jars in place of plastic or BPA–lined commercial cans.
Canned foods also keep most of their nutritional value longer. Approximately 30–50% of vitamins A, C, B (thiamin), and B2 (riboflavin) are lost during the heating process, with an additional 5–20% loss of these per year afterwards. Less sensitive vitamins remain intact over time and are found in only slightly lower quantities than in fresh food.
Vegetables hold up well and maintain much of their nutrition if handled and canned quickly. Another advantage to canned foods is that you can enjoy them right out of the container—no preparation required.
This great homemade strawberry chia jam recipe requires only four ingredients, and an easy heating, cooling, and canning to preserve the final product.
The Risks and Downsides Of Canning
Canning does come with some risks. Home canning requires a sterile environment to prevent contamination. Canned foods also need to be stored—airtight—at the right temperatures to prevent pathogens like botulism. A good rule of thumb is to follow these USDA guidelines and pay close attention to cleanliness, timing, and temperature to ensure you’re preserving uncontaminated food.
Aside from losing some of their flavor and nutrients over the years, canned preserves, jams, and jellies often use a lot of added sugar in their preservation process. Added sugar is a tremendous health concern in the U.S. because it has been shown to increase the risk of chronic diseases, such as diabetes, heart disease, and some cancers. These types of canned foods should only be consumed in moderation.
It is also important to note that mold can grow on canned foods, especially on the surfaces of high–sugar foods like jams and jellies. Mold can produce toxic compounds called mycotoxins, which can be carcinogenic. Luckily, mold is often colorful and easy to see. You can prevent mold through proper heat processing and airtight sealing. It is always a good idea to test the seals of your canning jars before storing them (in a cool, dry, and dark place).
2. Freezing
Freezing is another great option for preserving most foods. You can freeze soups, baby purees, oats, coffee grounds veggie burger patties, chopped fruit, and blanched vegetables to name a few.
A properly maintained freezer will store food for long periods, after which you can safely thaw (either in the fridge or in cold water) and cook as desired. Nutritionally, foods that you prepare at home and then freeze are almost always better for you than prepackaged frozen meals.
Freezing offers minimal risks, but keep in mind that everything in the freezer is subject to freezer burn, which happens when air comes in direct contact with the food. Freezer burn can look like grayish–brown spots, it won’t make the food unsafe to eat, but it does make it dry. These areas can simply be cut off after thawing. And while most foods taste very similar after freezing, some go through significant and sometimes unpleasant textural changes.
And as much as we’d like them to, frozen foods don’t have an infinite shelf life. Foods such as soups and stews, vegetables, and fruits can spoil after storing it a long time. To prevent storing foods in the freezer and forgetting about them, write the date on the container in permanent marker (I keep a roll of masking tape and a Sharpie in the kitchen for this very purpose).
Use or compost extremely old items regularly. A good rule of thumb is to store more recently frozen foods at the back and choosing to thaw and eat the older items at the front first. This creates a natural rotation and eventually cuts down on food waste.
3. Drying or Dehydrating
Drying or dehydrating are excellent preservation method for fruits, vegetables, and herbs. Drying food tends to concentrate its flavor, costs very little, and makes storage easier by reducing its size (produce is mostly made up of water).
Dehydration works by removing water from fresh food, which prevents bacterial growth. The moisture content of home–dried food should be around 20% or less. You can do this by using a commercial dehydrator, hanging bunches of fresh herbs to dry (unless you live in a high humidity climate), oven drying, or even using the sun to make your own solar food dehydrator. Before drying certain fruits and vegetables, it is a good idea to blanch them (dip them briefly in boiling water) to help preserve them best.
Dehydration does have some drawbacks. While many nutrients remain fairly stable during dehydration, vitamins A, C, and B (thiamin) are sensitive to both heat and air. One drawback of electric dehydrators is that they use a lot of energy. This can be avoided by using other home drying methods whenever possible.
Dehydrating food can also take time—often taking over ten hours—so be sure you’re prepared to be patient and do some planning ahead. Preparing foods for drying can take time as well, e.g.: slicing, coring and spreading out fruits on a drying rack, all of which needs to be done manually.
4. Fermenting
Fermenting foods is a great way to boost your intake of healthy probiotics (good bacteria) that are great for your digestive system and immunity. Fermenting starts with lacto–fermentation, which is a bacterial process that preserves and boosts nutrients in food.
The basic steps include chopping, grating, or otherwise preparing the raw food, deciding on the culture you’ll use (typically salt, whey, or a starter culture), preparing and adding brine, and placing everything in an airtight container in a cool environment. Fermentation does require a lot of care, as food can easily spoil during the process if not using fresh veggies, or distilled or purified water.
Fermenting typically uses a lot of salt, as salt helps preserve food by drawing out its water content and preventing bacterial formation. This can be a health drawback for people experiencing certain medical conditions. In such cases people should use fresh sauerkraut, kimchi, or other salty fermented vegetables as the “salt source” for their meals.
Kimchi is an awesome fermented dish popular in Korea. This Korean kimchi recipe uses traditional brining and fermentation to create a nutrient– and probiotic–rich condiment.
A Note About Mold
Mold is actually fairly rare in fermented foods, and there are ways to prevent it. First, use the freshest produce you can find, in an ideal world it should be organic. Next, choose the appropriate temperature for fermentation, which is between 65–70 °F. Last, use the right amount of salt—around 1–3 tablespoons per quart of water.
It can sometimes be difficult to gauge if fermented foods have spoiled. Sometimes a film may develop on the surface, but this may not necessarily be mold. Sometimes it is actually a harmless yeast called Kham yeast.
Other times fuzzy spots that are pink, black, green, or red may develop. These are a sign of mold. This doesn’t necessarily mean the whole batch is spoiled, as one can often remove the top layer and safely consume what’s underneath—so long as it smells and tastes okay. A good rule of thumb is “when in doubt, compost it.”
5. Pickling
Pickling can be done on more than just cucumbers. Many vegetables can be pickled as well. Some other commonly pickled foods include beets, cauliflower, peppers, cabbage, and even fruits like lemon or mango.
Pickling is preserving food in a high–acid solution, either via a process of natural fermentation or by adding vinegar and salt (and sometimes sugar) to prevent spoilage and extend shelf–life. Many combinations of pickled foods are colorful and make great gifts.
Very few ingredients are needed for home pickling. All you really need is the fruit or vegetable, a high–acid brine solution (water, vinegar, salt, sugar (optional), spices, and herbs), and an airtight container.
These easy, homemade refrigerator garlic & dill pickles take only 20 minutes to make. And you can adjust this easy recipe to pickle other vegetables, like these homemade refrigerator pickled beets.
6. Cold Storage
This is the most common way many of us store produce, whether in the refrigerator or in an underground root cellar if you’re lucky enough to have one. Cold storage produce, like apples, pears, root vegetables, celery, and cabbage can last up to several months when stored correctly.
It is important to follow ideal temperatures and conditions for food storage in order to get the longest shelf–life from them. Apples, for example, should ideally be stored at just above freezing, in a damp and breathable bag.
It may be tempting to bring fresh produce home and line it all up on the counter. But storing things too closely together can cause them to spoil faster. Here are a few basic rules:
- Store fruits separately from veggies. Many fruits and vegetables, like apples, cantaloupe, blueberries, bananas, potatoes, and tomatoes give off ethylene gas, which will ripen and brown anything near them faster.
- Store root veggies separately from aromatics (onions, garlic, ginger).
- To best preserve their freshness, some produce like apricots, grapes, strawberries, green onions, asparagus, and cut fresh herbs should go in the fridge right away.
- Avocados, kiwis, peaches, and pears should ripen on the counter first before storing them in the fridge.
- Never refrigerate pomegranates, mandarin oranges, ginger, jicama, potatoes, yams, sweet potatoes, squash, onions, and garlic, as they fare best at room temperature.
Things to Keep in Mind with Cold Storage
Maintaining the proper moisture levels is also important to prevent drying, wilting, or premature mold. Rather than storing produce directly on the counter, it helps to store them in containers with holes like baskets or mesh bags, to promote air circulation.
Most refrigerators have a fan, which it can dry out foods. The produce drawer is typically protected from this effect. Foods stored loosely in the fridge, outside this drawer, will dry out quickly if not kept in a bag, container, or otherwise protected.
Choosing fresh–looking produce at the store also helps prevent early spoilage. Unless you’re planning to eat them immediately, avoid avocados that are already mushy or bananas that are already spotting. Check produce to ensure it is not badly bruised, discolored, punctured or otherwise damaged.
It is also important to hold off on washing produce until it is ready to be preserved, cooked or eaten, as pre–washing can actually lead to mold formation during storage. Lastly, for those growing their own food, make sure you know when it is at its prime, so as to not harvest it too early or too late.
Try New Ways of Preserving Your Food
Nobody likes coming home or opening their fridge to find that the produce they just purchased with a hard–earned paycheck is already going bad or, even worse, no longer edible. If you’re looking for new ways to increase the shelf–life of fruits and vegetables, give some of these food preservation methods a try. You might find that knowing how to preserve food helps you save time, money, and reduces food waste.
Sources:
Food Storage & Preservation: How To Store Food Properly
https://foodrevolution.org/blog/food-storage-food-preservation/
Sep 6, 2019