Energy-Wise Cooking & Canning
Feeding Ourselves - It is all about nutrition and how to provide it, year-round, every day, multiple times. You can either:
- Eat things in their freshest state, which means for us means straight from the soil
- Store things that are still alive, in a state of "suspended animation"
- Preserve things through the one-time use of as little added energy as possible using solar drying or, as we will see on this page, steam-canning & steam-juicing
- Or you can use some continuously energy-sucking appliance to slow food's inevitable nutrient loss, a choice we would like to help you avoid
There is simply no point in using more energy to cook or preserve your food than what the food itself contains in calories. If you are aware of the distance most commercially available foods travel to reach your table then you may already be growing some portion of what you eat. That is a great first step! For those who wish to take the next step, avoiding unnecessary and wasteful use of precious energy sources in food preparation and preservation, we offer the following examples of what we do here at home.
First, the Energy-Saving Cooking (since we also need a heat source for steam-canning and juicing)
Direct Solar Cooking
This shows the two solar cookers we use. The home-built one on the left is more of a slow cooker, using a simple mirrored reflector above a covered cast-iron skillet set in a galvanized pan filled with vermiculite insulation. The parabolic dish on the right focuses the Sun's energy enough to bake, boil, or fry stuff. It was purchased many years ago from Zomeworks, in Albuquerque, NM. There is a Pyrex bowl at the center that holds either another inverted Pyrex bowl on top, holding dark-colored pots for boiling, or a steel rack that holds pans for baking/frying. Cooked food usually goes from here into an insulated, double-walled, stainless steel "hot box" (pictured further below) to stay warm or cook further.
Low-Voltage Electric Indirect Solar Cooking
This is our latest addition to the kitchen. Essentially, it too is a solar-powered oven. We started with the notion that we needed to divert more electricity from our photovoltaic (PV) solar array to other useful chores, since our home is "off-Grid" and our batteries are often already full. With our recent system upgrade to gain enough solar input to charge an electric car, the excess electricity can be quite substantial. So we came up with the idea of building a 12-volt electric oven, using DC electricity straight from the batteries and solar charge controller. The models available on websites catering to RV enthusiasts and over-the-road truckers simply were not built to last and were uninsulated.
We initially built this one using two recycled stainless steel tanks, a "barrel-stove" door kit, four 300-watt, 12-volt, (0.5-ohm) ceramic resistance heating elements, some heavy-gauge wiring, and about 7 gallons of horticultural vermiculite as insulation. The switches at the bottom front each added in one more heating element to the single 300-watt element that was active when the unit was switched on. With all four switched in, burning up 1200 watts of power, the unit could quickly reach over 550 degrees F. And the insulation keeps the temperature stable for long periods, greatly increasing the efficiency.
Recently we rebuilt the oven with two 30-watt heating elements (5-ohm elements rated for 300 watts at 36 volts, which, when run at 12 volts produce 30 watts) and two of the initial 12-volt, 300-watt elements. Now, when we manually switch it on at the breaker box, or when we switch the breaker that allows the charge controller to divert excess solar power to the oven automatically, a 30-watt resistor begins heating. The second switch adds another 30 watts, and the remaining switches each can can 300 more, for a total of 660 watts. The original heating power set-up simply proved unnecessary with this shape, size, and amount of insulation.
Here you can see the first pot of veggie stew coasting down to 150 F after cooking at 250 F for an hour. The heating elements are at the bottom, just below a ceramic floor tile that acts as a heat-retaining, heat-distributing oven shelf. It is supported by three 3/8" steel rods under the tile, just to make sure the heating elements are protected. We later replaced the tile with a 1/8" steel plate to make it less fragile.
This unit allows us to utilize sunshine while baking/cooking larger pots of food than what the parabolic cooker can handle. The cooker has a standard range outlet connection, allowing us to wheel it into the kitchen or our "summer kitchen", the sauna, when we do not want to heat up the house. When we DO want to use it as a "diversion load", to heat the house during winter, we just switch on a couple of heating elements (or let the charge controller do this for us) and leave the door open. This works well to utilize excess sunshine when we are already heating water with wood-stove fires at night and do not want to overheat the hot water tank by diverting sunshine during the day.
A Bit of Really Old Technology
This is the latest addition to our sauna. It replaces a tiny airtight box stove that was adequate for sauna heating but too small for much cooking. We wanted to be able to better utilize the sauna as a "summer kitchen", a quaint old custom from grandma's day, when she did not want to overheat the house with a cook-stove fire in the summer (since the only option was a wood-stove, not gas, electric, or a microwave!). A separate building was built outdoors, usually near the kitchen, for summer cooking. With screens on the windows and doors, the sauna does this for us also. This stove is from the early 1900's, built in Chicago, but with four of its cast iron top plates replaced with a single, less leaky, steel plate. Now we can do canning and steam juicing (not to mention regular cooking and baking) outside the kitchen when we do not want to overheat the house. These are often antiques but many firms offer modern versions which are usually larger. As you can see from the 36-inch wide corrugated steel on the wall behind it, this stove is not as small as what it replaces, but it is still small as wood cook-stoves go.
And its Updated, High-Efficiency, Mass-Surrounded Cousin
Here is a big reason we bought this wood-stove for our home's primary winter heat source. It can hold a lot of cook-pots. I had rice in one, beans in another, the wok had some veggies stir-fry-steaming, behind that is some squash steaming, and the skillet in front with the circular potholder is our version of a stove-top oven for flat-breads. There is a stainless steel cake pan with dough in the cast iron skillet, with a cast iron spacer under it, a stainless steel cover over it, and the insulating potholder over that. This was enough food for easily a couple of meals, all on one brief firing of an armload of "box elder" (Manitoba Maple, or Acer Nigundum). You can see more details of this stove on our Masonry Stove page.
The Most-Used Appliance in the Kitchen
And this device is a REAL energy saver in our home. Basically it is just two cheap, thin, stainless steel cooking pots with lids, one inside the other. The unit sits inside a large ceramic crock, just to hide it from view. The pots are joined together using polyurethane foam which acts as a highly efficient insulator. Even the lids are bound together with foam, creating a space that allows food that has reached the boiling point to keep cooking without an additional heat source. The same sort of device, in different form, has been used in many cultures, often called a "hay box" cooker. This one is simply a bit higher-tech.
Using it is so easy! And it saves so much energy normally used in cooking. For instance, beans can take hours to thoroughly cook. Instead, soak them in water overnight, drain and refill the pot with water, then bring them to a boil for 10 to 15 minutes (depending on the size of the bean) using whatever form of energy you currently use for cooking (gas, electric, wood, coal, peat, sunshine, whatever). Next you put them in a "retained heat cooker" such as this and wait for maybe an hour. Perfectly cooked beans come out! We use this thing anywhere from one to three times per day and would feel lost without it.
But, as with all beans in the genus Phaseolus (common beans), you MUST first boil them to alter a chemical that is especially high in red kidney beans. Failure to do so can cause poisoning, as you will find at this link. Definitely read it if you currently use a "slow-cooker", which does not actually reach the boiling point!
Construction of this "hot-box" involved first putting a 1.5-inch, solid polystyrene foam block in the bottom between the two pots to maintain a space. Next I spray-foamed the area between the pots with polyurethane caulk, starting low and spiraling up with the caulk can until the space was slightly overfilled. The lids were set upside-down with a rigid foam block between them and similarly foamed with polyurethane caulk. Excess foam was then trimmed from the pots and lids and clear silicone caulk was applied thinly to each raw foam surface. Then waxed paper was cut to sit flat on the silicone smeared on each side. The waxed paper acts as a "release agent", allowing the lids and pots to conform to each other without sticking. The lids were pushed down onto the top of the pots and the silicone was allowed to cure. Excess silicone and waxed paper were trimmed off the next day and the unit was ready to use.
Another way of using extra solar power
We recently tried some experiments designed to cut our use of fossil fuels even further by attempting to generate our own cooking gas instead of using compressed propane (LP gas) for some of our cooking needs. While this proved less than fully successful in our rather cold climate, even during a record-breakingly hot summer that should have generated plenty of gas, we tried another approach which has worked quite well. Pictured above are two 120-volt AC electric cook-top units, one using 1500 watts, the other 900 watts. We initially bought the one on the right locally and it worked well for most of our cooking but it could not replace gas as a heating source for canning foods. It simply would not put out enough heat once its cast-iron top plate reached its maximum temperature, at which point the unit would turn off and on repeatedly to maintain that temperature. The heater would not sustain the hard boil required for canning unless you were willing to wait seemingly forever. So we bought the unit on the left online and we use it almost exclusively for canning as its output is easily high enough to do the job. We can actually turn its temperature (duty cycle) control down a bit and it will still sustain a full, rolling boil in the canner. If you have an inverter large enough to handle the load, and enough solar electrical input to maintain your other needs even on cloudy days, these cook-tops can use the excess solar energy that is inevitable on really sunny days. They are especially handy when intermittent clouds lower the temperature of the direct-solar parabolic cooker too much.
Then, the Energy-Saving Canning and Steam-Juicing
What can we do with all of these highly perishable berries? Steam-Juicing!
This is a typical daily harvest of raspberries from our patch. The variety is Autumn Bliss. This is what's left after we've eaten what we can handle fresh! What to do with the rest when you're maxed out on "raspberry this" and "raspberry that"?
We put two day's harvest into our stainless steel steam-juicer (after holding the first day's picking in a cool spot). This will remove the Pasteurized juice for bottling, leaving the pulp and seeds behind. The pulp-seed mix can be solar dried (on cookie sheets as a "fruit leather") or canned in the steam-canner, depending on the weather. Blackberries really need their seeds removed from the pulp before canning or drying as they are larger, more numerous, and more "gritty". There are various appliances available for doing so, most of them simple hand-cranked devices.
This is the fully (and obviously well used) assembled steam juicer. The bottom pan holds about an inch or so of water (instead of gallons of water!) that boils to make steam. The steam rises through the next layer, which is where the juice collects. The third layer, most of which is nested in the second, is the perforated basket of berries. The top layer is, surprise!, just a top. The silicone hose hanging down the front has a clamp on it to retain the juice until you're ready to tap it off. And to reduce distillation of water into the juice pan (from the cold stainless top), especially before the berries get hot enough to release juice, we normally run it with a folded towel on top for insulation. Our biggest use of the steam juicer probably occurs when we do tomato processing. We quarter our canning tomatoes and extract a lot of the juice, bottling it for soups and fresh drinking. We then pack the remaining pulp into quart jars and steam-can them. No boiling is required to get a thick sauce, and the small quantity of water used (compared to boiling water bath canning) really saves a lot of time and energy!
And this is the result. Seven, 16-ounce, recycled "Grolsch" beer bottles hold the product of the process (actually there was one more that I removed from the juicer and heated to boiling separately after the juicer had cooled and the pulp dripped totally "dry"). The bottles get filled to the top with hot juice, straight out of the hose, the top is clamped on with the wire bails, and you're done! Well, actually just a little bit of rinsing to do on the outside of the bottles from the overflowed juice. We fill about 200 of these bottles each year, primarily with apple juice. We don't use the steam juicer for apples because of the volume we do. Before we sold the equipment to someone doing an even higher volume of apples we hammer-milled the apples into a pulp and pressed the pulp in a hydraulic press we designed (built by a local metal shop). Now we simply run the apples through a medium-sized cone-shredder on our Kitchen-Aid mixer. Then we strain the juice, heat it to boiling, and pour it directly into the bottles. No further processing necessary!
Here you can see the process of preparing some small pears for juicing. The raw product is in the wire egg basket at the top. The knife and edge-sharpened spoon used to cut the pears in half and scoop out the cores are at the bottom left. The pulled-out stems are above them and the the pear halves. The cores that are about to become treats for our sheep are at the left. And the cut-up pieces of pear are in the steam juicer. A steam juicer full of cut pears made over 7 pints of very sweet juice and 4 cookie-sheet trays of fairly dry pear pulp for the solar food dryer. You would not think that this pulp would have much flavor, but even with lots of juice removed the heating that it undergoes during solar drying tends to sweeten it (semi-carmelization) and concentrate the flavor. Just try to avoid eating a second piece!
Of course steam-juicing can be used to preserve almost any acidic juice. We use it for apples, pears, peaches, plums, grapes, strawberries, raspberries, aronia berries, and even, as we are about to see, tomatoes. When we steam-juice a full pot of tomatoes we get about 7 pints of juice and about 7 quarts of tomato pulp left in the juicer. With so much liquid removed already, canning what remains gives you a ready-made tomato paste, especially if you use any of the available de-seeding machines (Victorio strainer, etc) to remove seeds and skins.
Steam-Canning - A Handy Energy-Saving Adjunct to Steam-Juicing
This photo shows a 7-quart batch of multicolored heirloom tomatoes after steam-canning. The canner consists of a shallow stainless steel pan filled with about 1.5 inches of water. The jars sit on a perforated stainless steel plate directly above the water. A deep lid, shown behind the canner, covers the jars to contain the steam. With this little water to boil, compared to boiling water bath canning, you can see how you save loads of energy bringing it to the boiling point. Some have criticized steam-canning as an "unsafe" method, but this is because of incorrect timing. Steam-canning takes the same amount of time as boiling water bath canners. The difference lies in knowing when to start timing a batch. Boiling water bath times start when you see the water boiling. Steam-canning times start when you see the two vent holes at the lower edge of the lid pouring steam out horizontally in foot-long streams, not just little occasional puffs.
The tomatoes shown are a mix of open-pollinated heirloom red, orange, and green-skinned varieties, and we usually just can them without removing skins or seeds. Their depth of flavor more than makes up for any aesthetic abnormalities or seeds stuck between your teeth!
Our Latest Book
If you are looking for more detail than can be gathered on our site, check out our book:
Lots of folks have either downloaded or purchased a hard copy of "Pantry Full of Sunshine", Larisa's book based on many of the questions she fielded at workshops about her unique solar food dryer and her other energy-saving food preservation methods, like steam-juicing and steam-canning.
Our latest co-authored book, "Feeding Ourselves", now in its second edition, includes all of "Pantry's" information plus it is greatly expanded to show how food preservation fits into our overall scheme of nourishing ourselves year-round in a fairly harsh climate. And once again it has been updated to better reflect our most recent dietary changes, including entirely gluten-free, whole-food grain recipes and more about harvesting and using local nuts, with additional information on growing and processing home-grown foods of all sorts. If you liked "Pantry", or the first edition of Feeding Ourselves, you will love this one!
From the back cover of Feeding Ourselves: This book came about after many decades of trial and error in the quest for real, homegrown, organic local cuisine throughout the entire year. We've been gardening and preserving food to fuel our off-grid homestead lifestyle since the 1970's, determined to sever our reliance on the petrol-fueled American food system. Some of our explorations led to us to rediscover and integrate old methods, like root cellaring, into our routines. Other experiments resulted in the design of our solar food dryer. Our approach to this effort is from a vegan, gluten-free perspective. Over the years, Larisa taught workshops on food preservation, including many summers at the Midwest Renewable Energy Fair. In 1997, she decided to write a small book, "A Pantry Full of Sunshine" which she self-published to answer the frequently asked questions that couldn't be covered in an hour-long workshop. Now, over a decade later, this little book's limited scope became evident and we felt that there was much more to reveal about how we put food on our table. This seasonal guide features down-home advice from Minnesota. There is a focus on energy efficiency, both in cooking and food preservation. Whether you want to grow and eat vegetables, fruits, legumes, grains, nuts, seeds, herbs, spices, or sweeteners, we hope our approach will inspire you to explore feeding yourself, from the ground up. We intend this book to be merely a source of ideas and food for thought. While this is what works for us, it may not suit you, and is not meant to be a detailed plan of action. Feel free to creatively adapt our ways to fit your circumstances. Enjoy the abundance!
To see an Adobe PDF file of the second edition's covers and table of contents, just Click Here.
- Physical copies of "Feeding Ourselves" (184 pages, spiral-bound) cost $23.50 each, postpaid in the U.S. (please add $1.38 sales tax if you are ordering in Minnesota), or $20.00 plus shipping elsewhere in the world. Contact us for international shipping costs. All others can simply send a personal check, traveler's check, or postal money order to:
30319 Wiscoy Ridge Road
Winona, MN, 55987-5651
- OR: To order a physical copy of "Feeding Ourselves" using PayPal, Click Here. Clicking this takes you (very slowly if you have a dial-up connection) to a new screen with a "Buy Now" button, and this links to PayPal's secure order form where you can pay by credit card, checking account, or an existing PayPal account balance.
- OR: To order a downloadable Adobe PDF file of "Feeding Ourselves" for about half price ($10.00), just Click Here (requires a free Adobe Reader download to read the PDF file). Clicking the book download link takes you to PayPal's secure order form and gives you a link to the PDF via Payhip.com. The file size is over 8 MB so, depending on your connection speed, it may take some time to download.