Induction Stovetops

“God will provide the victuals, but He will not cook the dinner”- Proverb

There are five primary ways to cook food in a home:

1. Fireplace cooking (rustic but fun)
2. Gas stove/oven (same principle as a fireplace but you control the flame)
3. Electric stove/oven (using the “waste” heat of an electrical circuit)
4. Induction (magnetic field)
5. Microwave (waves vibrate food molecules)

Of these methods only a Microwave cooks the food directly. Typically all other methods first heat a cooking vessel and the vessel then cooks the food. Think of the times you wait for a skillet to warm up or burn something because the pan is too hot.

In this post I want to discuss Induction stoves. My wife & I were looking at new stoves the other day and most of the stoves on display were Induction. Neither of us has ever used one. How do they work? [The numbers below match the picture]

1. The “burners” (or more accurately called the “elements”) pulse electricity through copper coils to create an oscillating magnetic field.

2. The field extends just above the element and into the metal of the cooking vessel. This creates an electric current INSIDE your pan/pot, which generates heat. Essentially the cooking vessel becomes an electric heating element.

3. The heat of the pan/pot cooks the food.

4. Nothing outside the cooking vessel is affected by the magnetic field.

In order for Induction to work, the cooking vessel must react to magnetism. That’s yes for iron and steel, no to materials like aluminum, copper, and Pyrex. If you’re not sure, try the magnet test. A vessel is ferrous (i.e. subject to magnetism) if a magnet will stick to it.

Induction Pros

• Heat faster with the fine control of gas cooking.
• More energy-efficient than traditional cooktops (90% vs 70% for electrical units)
• Safer. The hottest thing is the pan itself, not a flame or an electrical element which can be quite hot.
• Cleaner – ever try to clean a spill on an electric element? The induction element surface is perfectly flat and wipable.
• In Consumer Reports, 2008, induction appliances outscored gas and electrical ovens.

Cons

• Won’t be able to use your copper, aluminum or Pyrex pots
• Pot & pans need to have a flat base to make contact with the magnetic field. A rounded Wok won’t work so well. (I did read that China makes rounded induction elements just for woks!)
• Pans heat really fast! Say 10 seconds. This would normally be considered a plus but it also means you’re likely to burn some food until you get used to it. It is suggested that you always put some oil or liquid in the pan before turning on the heat – this will help buffer the heat.
• The Induction magnetic fields could interfere with a pacemaker or defibrillator.
• Metal jewelry like rings and bracelets can become hot if your hand hovers over an active element. Many modern induction units have sensors and only activate the magnetic field when a “lot” of metal is detected – a pot’s worth instead of a ring or bracelet.
• Noise – some induction stovetops have an internal fan to keep the electrical parts of the elements cool. Some pot and pans will hum or buzz on an induction stove.

Bottom Line

While there is no “flame” with Induction cooking you still have to take precautions. The metal pan will become hot and will still burn you. When you pick the pan up, the stovetop that was directly under the pan is still hot from the heat of the pan and needs a moment to cool before the stovetop is safe to touch.

Resources:
http://theinductionsite.com/
http://en.wikipedia.org/wiki/Induction_cooker

Camp Stoves - Sterno

The ultimate camping trip was the Lewis and Clark expedition.” -Dave Barry

The best know of alcohol cooking fuels is a jellied alcohol called Sterno. Two tablespoons of alcohol fuel will boil two cups (1 pint) of water in five minutes under ideal conditions (not windy). The flame is not hot and is best used to warm foods instead of boiling.

One 8 oz. can of Sterno fuel, about the diameter of a can of tuna fish and twice as
high, will allow you to cook six meals if used frugally. A can will last 2.5 hours but can be extinguished and relit for later use. Sterno is frequently used indoors to warm chafing dishes. But as this article notes, even Sterno can cause carbon monoxide poisoning if it is deprived of sufficient oxygen.

Sterno evaporates very easily, even when the lid is securely fastened! It is not a good fuel for long-term storage. If you use Sterno in your 72 hour kit, check it every six months for evaporation.

Sterno is more expensive than gas and liquid fuels but it is extremely convenient, safe (non-spill, not pressurized), and ultra-portable. It works in extreme cold and low pressure (like the top of Mt. Everest) when other stoves fail.

http://zenstoves.net/Sterno.htm

Bottom Line

"If you want the lightest, most compact, most reliable stove on the market, buy a can of Sterno. Yes, it takes 10 to 12 minutes to boil water ... My Sterno stove fits inside a 16-ounce cup. Throw a book of matches and a bandanna into the remaining space in the cup and the whole thing weighs 11 ounces and will serve you on a 6-day hiking trip. What's not to like?" - Kent Forrester

Camp Stoves - Pressurized Gas

"Camping is nature's way of promoting the motel business.” - Dave Barry

A pressurized gas stove looks like a liquid gas stove - it has a flame burner with an attached fuel canister. The difference is the contents of the canister if it leaks. Coleman fuel (discussed yesterday) will leak as a liquid but Propane and Butane will escape as a gas. And while you can refill your liquid stove with fuel, for gas stoves you must buy fuel canisters already filled and pressurized.

Propane & Butane are "safe" for indoor use as they produce carbon dioxide (not monoxide) while they burns. Still you should crack open a window because it does consume some oxygen in the room. The primary hazard of using propane indoors is that leaks will "pool" in low areas since it is heavier than air. Your hot water tank could ignite an explosion if leaked propane pools in the basement.

Propane stores indefinitely, having no known shelf life. Propane stoves and small portable heaters are very economical and simple to use but the storage of propane is governed by strict local laws. Check out your local ordinances.

Like Coleman stoves, gas stoves and grills allow a fine control over cooking temperatures - just like a home stove. My wife and I often see Butane stoves used in cooking demonstrations at fairs.
The most difficult aspect of gas canister stoves is finding the right canister. They are non-refillable and often custom made for each stove manufacturer. Old canisters must be safely disposed of (they remain potentially explosive). It is also very difficult to know how much fuel is left inside a canister.

Gas stoves do not operate below 0 degrees Fahrenheit.

Bottom Line

It will be interesting to see if Butane stoves replace the Coleman stoves in popularity. Less mess and easier to use but at a higher fuel cost.

Camp Stoves - Pressurized Liquid

"If you're not in New York, you're camping out.” - Thomas E. Dewey, NY Governor

Pressurized liquid stoves (like kerosene and white gas) are very popular with campers. When my parents camped, we used a Coleman two burner stove for cooking. Single burner stoves are great for hiking and survival. Some models are "multi-fuel", able to burn kerosene, unleaded gasoline, diesel, white gas, and even jet fuel.

Liquid "gas" operates well in very cold weather (sub-zero Fahrenheit) and is cheaper than pressurized gas like propane. It is readily available world-wide. Liquid gas stoves are the most difficult to get started. They must be pumped/primed/pressurized before starting. While white gas (Coleman fuel) is relatively clean, burning other fuels will create soot that will eventually clog
the fuel lines and require a cleaning.

Liquid gas is very flammable and so is anything it gets spilled upon. Do NOT use liquid fuel inside a tent and be very careful when pouring the fuel outside.

White gas stoves (Coleman) are fairly easy to use and produce a great amount of heat. However they produce vast amounts of carbon monoxide. NEVER use a Coleman Fuel stove indoors. Never store white gas fuels in the house or near a heater, it is highly volatile and can explode under the right conditions.

Coleman fuel has a tendency to evaporate even when the container is tightly sealed so it is not a good fuel for long-term storage. Because of its highly flammable nature great care should always be exercised when lighting stoves and lanterns that use Coleman fuel. Many serious burns
have been caused by carelessness with white gas.

Kerosene (Range Oil No. 1) is the cheapest of all the storage fuels and is also very forgiving if you make a mistake. Kerosene is not as explosive as gasoline and Coleman fuel. Kerosene stores well for long periods of time and by introducing some fuel additives it can be made to store even longer. Do not store kerosene in metal containers for extended periods - the moisture in it will cause rust. A 55 gallon drum stores in the back yard, or ten 5 gallon plastic containers will provide fuel enough to last an entire winter if used sparingly.

Bottom Line

I had no problem priming Coleman stoves and lanterns as a child. I continued to use Coleman in my college days as I traveled and camped and have fond memories of the meals I cooked.

http://www.endtimesreport.com/BF-2412.html. http://www.coleman.com/coleman/ColemanCom/category_main.asp?CategoryID=2000

Travel Notes

Always let the pressure out of the fuel canister when you finish cooking. Never travel with a pressurized canister.

Coleman has a web page about airplane regulations and trying to take your stove with you when you fly. http://www.coleman.com/coleman/msds/travel.pdf
The pressurized fuel canisters are forbidden and must be removed from the stove. Some carriers will not allow any previously used fuel-burning appliance to be transported. Coleman fuel-burning appliances should be declared to the airline prior to transporting, whether checked in or with carry-on luggage.

Camp Stoves - Esbit

"Some national parks have long waiting lists for camping reservations. When you have to wait a year to sleep next to a tree, something is wrong.” - George Carlin

As discussed in my blog two weeks ago, there are four kinds of portable stoves that can be used for camping, during power outages, or when you need an extra burner. Some are safe for indoor use (kerosene, propane, Sterno) while some are not (Coleman fuel/white gas, esbit).

Today's blog will look at solid fuel like Esbit, hexamine, and trioxane tablets. These tablets have a high fuel density and do not liquefy while burning. They are light, easy to carry and there is no danger from "spillage". They can be extinguished and saved for re-use. They make excellent fire
starters for camp fires.

They are smokeless and ashless but not odorless. Solid fuel can emit noxious fumes like cyanide. Food should be cooked in closed pots. Hexamine should not be used in enclosed spaces like a tent or indoors. Solid fuel will leave a sticky dark residue on the bottom of pots.

Esbit tabs weigh 1/2 oz each and will burn 12-15 minutes. Using an aluminum foil windscreen or mini stove, Esbit will bring a pint to boil in 8 minutes. One and a half tablets will boil a liter.

Bottom Line

Esbit is ideal for back country hiking and camping. It is super light and safe (when used in open air). The heat is intense but small in size. Boiling water can be slow but an egg will fry fast. The high heat is suited for boiling not simmering. It is excellent for making hot drinks, stews, pasta and other one pot meals. Given the high cost and short life of solid fuel it is not suited for baking, grilling or roasting.

www.rei.com/product/653343

http://en.wikipedia.org/wiki/Esbit

FYI
Esbit was created in Germany and stands for "Erich Schumms Brennstoff in Tablettenform"; i.e. Erich Schumm's Fuel in Tablets.

Cooking without power

"I was 32 when I started cooking; up until then, I just ate.” - chef Julia Child

The recent Survival Encyclopedia blog post got me thinking about cooking at home without power. We have an electric stove so if the power goes out, no stove! If you have a gas stove, it could be risky to use post earthquake and other emergencies where the gas lines might have been damaged. So what are your options?

1. Don't Cook: Keep a food supply of peanut butter, tuna fish (with a manual can opener), crackers and other foods you like to eat uncooked.
2. Use your fire place: If you have a fire place learn to use it for more than roasting hotdogs. Buy a dutch oven (a cast iron pot) and practice old fashioned cooking. Remember to cook over the coals, not the flames.
3. Use your BBQ grill: a grill (either charcoal or gas) is a great emergency backup to your stove.
4. Use a portable stove: these come in at least four varieties.

• Solid Fuel Tablets - good for boiling a cup or small pot
• Pressurized Liquid - Coleman fuel stoves
• Alcohol Fuel - safer but not as hot
• Pressurized Gas - Grocery stores now sell single burner Butane stoves that are just like cooking on a gas stove. This also includes a propane gas grill.

Bottom Line

For the next week I'll go into more details about these cooking methods. Try them out!

For more ideas on cooking without your stove see,

http://sharonastyk.com/2008/03/18/the-tools-we-use-part-i-making-dinner-without-a-conventional-stove/

http://www.thefarm.org/charities/i4at/surv/heatcook.htm