Making the Most of the Seasonal Bounty
Editor’s Note: It’s that time of year where we think you need to think about how you can continue to eat local the rest of the year. As we explain in our guide, there’s good reasons for doing your thinking now. Looking for special tomato advice? Look here and here.
Make Plans to Eat Local Later
Freezing, canning, drying, pickling, and cellaring are all methods for making plentiful local foods last through the hard fall and winter months. Eating locally does not need to be a hobby during market season. Preserve and store so you can eat locally all year long. The reasons for eating local do not diminish with the temperature.
There are simple ways to make the harvest last, like throwing some food in the freezer. There are also complicated ways to preserve summer’s bounty (have you ever tried canning tomatoes?). Some methods take investment and space, like buying a spare freezer. Other methods require ingenuity, like finding a cold spot for a root cellar. In this article we’ll introduce the concepts, techniques and issues related to food preservation and storage. Look forward to future features on these topics as well as blog posts and forum discussions. We look forward to your questions and comments, and we want you to share your experiences.
Watch the calendar
Mother Nature does not fool around with Chicago. The calendar flips a page, the weather flips a switch. Oppressive humidity leaves while clouds and rain arrive (more often). The end of the summer is harvest time, the peak of local food supplies. As consumers, we can find local food as accessible and as affordable as it will be all year in mid September. Likewise, the farmer’s markets are so full you cannot eat all that is there. As harvest time ends, we enter an extended period, from November through to May, where the Chicago-based locavore will need to draw upon storage in order to stay local. You’re at an advantage if you can do something with the seasonal bounty to make it last throughout the colder months.
Harvest Time Action
Preservation and storage need not begin at harvest time. Peas, broccoli, blueberries, available mid-summer, freeze well. Nevertheless, the bulk of saving starts as summer ends. Local is more accessible and affordable during peak times. Take advantage of the $16 bushel of tomatoes. It is also at this time of year that the best keeping crops, the apples and potatoes and onions meant for the long-term, come into the markets. Plus, you probably don’t have a cool spot in your house the middle of summer. Thus, now is the time to focus on preservation and storage.
Choose the right foods
Good storage and preservation begins with the right produce. Certain varieties of fruits and vegetables are bred for storage. In addition, potatoes and onions need to be “cured” to enable them to last. Ensure you start with the right stuff. Summer apples like Lodi and Transparents are not meant to keep (unless made into sauce), while colder-weather apples like Rome Beauties or Granny Smiths store very well. Likewise, some tomatoes, especially the plum types, are better for canning. Talk to your farmer about storage. Ask them about which apples, pears and onions are best for storing and preserving. No one knows what foods keep in storage better than the person growing them.
Choose the right method
There are several methods to preserve and store the harvest. Different methods work best for different types of foods and different methods produce different kinds of dishes. A pickled green bean is very different from a frozen green bean. Don’t pickle everything unless that’s what you want to be eating.
Some methods require specialized equipment, skills, space, or simply an investment of time. The desire to freeze is tempered only by the amount of freezer space you own. The desire to can is often tempered by free time.
Food can last two ways: It can be kept at the right temperature and humidity to slow it from spoiling or it can be treated in a way to eliminate the bacteria that cause spoilage. Listed below are the most common methods of food preservation and storage.
The US Department of Agriculture sums up freezing with this statement, “You can freeze almost any food.” They also add that freezing works because “freezing to 0 F inactivates any microbes–bacteria, yeasts and molds–present”. Finally, the USDA notes that freezing “prevents the growth of microorganisms that cause both food spoilage and food borne illness.” Not only does freezing work, it is easy. After minimal processing, the freezer does all the work. On top of all that, vegetables frozen at the peak of their freshness have more nutrients than many vegetables on the grocer’s shelves in Winter.
Freezing keeps fruits and vegetables closer to fresh than through canning. Compare a canned green bean to a properly frozen green bean and you will taste a difference. While any fruit or vegetable can be frozen, the best vegetables to freeze are those that are eaten cooked. Vegetables eaten raw like cucumbers and lettuces are not good candidates for freezing, although you can freeze something like a cucumber after juicing it. A few vegetables like onions and potatoes are better stored than frozen. The rule here would be, if you can store in a cellar (so to speak), store it there. On the other hand, there are certain vegetables that are especially suited to freezing including peas, sweet corn and various beans. Corn frozen immediately is generally going to taste fresher and sweeter than corn left around for days. Most fruits freeze well too.
Freezing is an excellent tool for preservation but for one key fact, it requires freezer space and electricity. The ability to freeze much depends on the ability to invest in freezer capacity, and just as important, having space for freezer capacity. Room for a freezer may be especially limited for apartment dwellers. The good news, freezers themselves are not exorbitant. Chest style freezers can be had for less than $300 and full size freezers can be had for less that $500 based on a recent visit to Sears.com. Energy-effiicent models will not introduce a significant increase to your energy bill.
Freezing vegetables require one small bit of preparation. Vegetables must be blanched, a process of quickly boiling and then cooling the vegetables. Blanching deactivates enzymes in vegetables that cause vegetables to mature, i.e., get tough or otherwise have off-flavors. (Instead of blanching, vegetables may also be briefly nuked in your microwave.) Fruits do not need to be blanched, but can be packed by themselves: “dry pack” or in a sugar syrup. Packing in syrup may lessen freezer burn, but it is not necessary. Fruits can be frozen with their skin on, even whole. Two good rules to follow when freezing anything : 1)spread items on trays to initially freeze; the flow of cold air over the food will enable the items to freeze faster and prevent them from freezing in blocks. 2) do not put hot foods straight in the freezer, such as just blanched veg; this will warm up your freezer.
Do not forget that another way to store items in the freezer is to convert them to ice creams, sorbets and ices. It is not much work to make a watermelon granita. This can provide nearly the experience of eating watermelon long after summer ends.
Other freezing resources:
- GardenGuides: Freezing Vegetables (for information on specific vegetables)
- Colorado State University: Guide to Freezing Vegetables
- FDA: Freezing and Food Safety
Cold storage, whether in true root cellars or not, is the another way to store food. We use “cold storage” as a catch-all phrase to cover foods that can last with decent care and not much else. Cold storage may seem the easiest step of all as no processing is required–in fact many foods for storage, like onions and potatoes, are processed or “cured” for storage by the farmer. The apparent drawback to cold storage, obviously is: who the hell has a root cellar these days? There are ways around that, and besides, there are some items that do not need real cool conditions to last. Food can last a surprisingly long time with good storage habits.
There are two classes of foods that can be stored. First, there are foods that need a cold setting (ideally between 32 and 40 F) and moist environment to stay vital. Then, their are foods that need a dry environment and generally should be kept around 50 F (or lowe). Onions, garlic and winter, or hard squash, fall into the latter category. They need to be kept dry. Onions should also be kept dark to prevent sprouting. Fruits and vegetables to be stored the other way, the cold way, include most root vegetables (turnips, rutabagas, carrots, parsnips, horseradish, beets, etc.); cabbage, potatoes, tomatoes, sunchokes, apples, celery and grapes. As discussed, make sure to choose the right types of apples and potatoes for storage. If in doubt ask the farmer. Many sources suggest wrapping tomatoes in newspaper for storage. Also, items like celery and grapes will last a long time in good cold conditions, but taken up a few degrees will quickly fade. Other items, like apples and potatoes have more wiggle-room when it comes to conditions.
Finding storage for onions and squash is easy because they do not require as cool conditions. Most homes in the North are plenty dry for these things. It’s the other fruits and veg that are harder to store. The first step to home storage is to identify a place or a way to keep food in that 32 to 40 range. The obvious location that stays in that range is a refrigerator, an excellent tool for long term storage. There may be other places in your house or apartment. An un-heated attic works very well. Food can also be placed in containers just outside the house such as in a window well, the stairs leading to a basement or an apartment porch. The residual heat of the house is usually enough to keep food from freezing, but if food is kept in containers, it can also be moved inside on truly cold days. A little ingenuity can find the cool spot.
A cool spot works only so well. The other critical step to keeping foods edible is to keep them moist. Traditional root cellars were dank. Modern takes on root cellars need the dankness added. This can be done by keeping pans of water in your improvised cellar, using wet burlap, or by placing the items in sand. Items kept in the refrigerator are especially vulnerable to dry conditions.
If there is one step to cold storage it is to visit your food. The best storage methods will not protect all. An apple here, a potato there, will spoil, and as the cliche knows, one bad apple will spoil the whole bunch. It important to keep a vigilant eye on the food put-away in cold storage.
Cold storage resources:
- Making a root cellar from your old fridge
- University of Missouri: Guide to cellaring fruits and vegetables
- BBC: Root Cellars dig a hole and you’ve got a cellar
Canning is the antithesis of freezing. It requires a significant amount work. Foods for canning must be chopped and peeled and stemmed and seeded. Before getting to canning, recipes must be followed, food prepared. Then, there is the work creating a good and clean environment. Jars must be sterilized. It seems scary and mysterious. Those recipes have to be followed or canning can produce un-wanted results. Canning, however, also allows for storage without the investment and space of a freezer. A few items like tomatoes may come out better canned than froze. Canning also allows the Chef to extend their harvest with all sorts of pickles, relishes, chutneys, jams and jellies. These foods add variety and vigor to a bland winter diet.
Food can be stored in cans (glass jars) because of steps taken to inhibit bacteria growth and steps taken to seal food off from all the bad things floating unseen in the air. There are two ways of canning: hot water canning and pressure canning.
Bacteria growth can be inhibited by the acids in foods or by introducing acids such as the vinegar in pickling solutions. In high acid situations, a hot water can is enough. When foods are low in acid, typically most vegetables, something else is needed to control bacteria: heat. The pressure in a pressure-canner makes water boil at a temperature over 212 F. This higher temperature kills bacteria. After this, proper use of hot water or pressure-canners will produce sealed jars. What started safe will remain safe.
Drying allows food to last by making it harder for bacteria to prosper. Bacteria needs water. Dried foods are not fully safe from spoilage. After drying it might still be necessary to freeze or seal the foods or at least kept in good storage conditions. Good candidates for drying are tomatoes, plums, and hot peppers. Many herbs can be dried for future use.
Home drying can be done with a dehydrator, a microwave or an oven. Like canning, dried foods, at least some dried foods, need some work before the actual preservation. Dried tomatoes should be cored and halved, although opinions differ on the need to seed tomatoes when drying. Fruits need to be pitted. Fruit leathers take more work.
Other Food Preservation Methods
Canners and freezers are wonders of modern innovation. Traditionally, many foods were preserved through fermentation. Fermentation flips the principles already discussed on their head. Canning, drying and freezing thwart microorganisms. Fermentation fosters them. Good bacteria’s and yeasts that can make food last. Fermentation is used to create products like pickles, kimchi and sauerkraut. Still, once fermented, products are often then processed, via canning or freezing, for additional storage.
Like fermentation, there are other ways to prolong food life without fully preserving it. In other words, if you pickle or jam, the new food will last a good long time in the refrigerator, but it will not last outside the fridge, let alone forever in the fridge. There are traditional cooked dishes that also serve to semi-preserve foods. For instance, the Sicilian caponata mixes eggplants and other summer vegetables in a sweet-sour-salty recipe that can be used in various ways on the table. Pestos, combining herbs, nuts and cheeses, are another way of making things last.
Other ancient methods for preserving foods used oils or vinegars. Oil makes a decent barrier to spoilage. In older times, meat was often preserved under fat. Now, we can keep roasted peppers or dried tomatoes around for longer periods by keeping them in oil. Flavored oils and vinegars may not keep a food, but they will keep the essence of a food. Likewise, fruits can be kept in alcohol. The most treasured method of saving fruit is to juice it and then make that juice last by making wine.
There are many ways to preserve the bounty of the harvest. Which way you chose will depend on what you want to preserve as well as the ways you have to save it. The more you eat local, the more you are going to want to eat local after the harvest ends. Over time, you will find preservation methods that work for you. You will invariably learn new ones. It is impossible to know how much to store and preserve without living through a Fall, Winter, and Spring with limited fresh foods. Try. Try using the methods discussed here. The reasons that have you eating local now, should have you eating local then. So give it a try.
- Wild Fermentation – The guru of fermentation, Sandor Katz
- National Center of Food Preservation: How do I ferment?