(Continued from Part 2. This concludes the article.)
The first issue when I started was using the pressure cooker even though the gasket had some very small wrinkles along one surface. On the previous two experiments the pressure hadn’t gotten above normal and the gasket held. The second issue developed after Experiments #1 and #2. The lid was harder to turn into place so I applied butter to act as a lubricant for this third experiment. The owner’s manual suggests a little mineral oil if a small amount of lubrication is needed. Too much butter making the gasket too slippery was the probable cause for the gasket blowing out at the end Experiment #3. The wrinkled gasket probably didn’t help. Take-home lesson: when the manual says to not use an imperfect gasket, they mean it! Another important lesson: if anything is amiss with a pressure cooker such as the lid being harder to turn than normal, figure out what the problem is before using it.
To try the blowout-plug test again, I removed the gasket butter with hot soapy water. I’d be standing back 20’ so if there was a malfunction again, no problem. Unfortunately, the test failed because the gasket was damaged enough that the lid wouldn’t seal and pressurize, all I saw was steam was coming out from under it. My first three experiments showed a pressure cooker can often work normally even when slightly defective, but the last experiment showed how dangerous it can be when it gets under abnormally high pressure. For that reason, don’t ever use a gasket with even small defects. Replacement gaskets are inexpensive and as always, two is one and one is none.
My more expensive pressure cooker uses an O-ring instead of a gasket and it sits in a groove making it impossible to blow out, thus allowing the pressure-relief valve to do its job.
Much to my chagrin, with the aluminum cooker out of commission I had to use my smaller steel pressure cooker for the safety-plug test as well as for redoing experiment #3.
I set the experiment up as before, on the stump with my butane stove. I knew from experience that once the pressure peg moved into place locking the two handles together, it would take another 2½ – 3 minutes for the pressure to get high enough to start rocking the cap. The three minutes passed and I was expecting that a minute or so after that, the blowout plug would be docking with the space station to deliver some fresh hot chili.
Surprisingly, it took seven or eight minutes before it finally blew.
Suddenly, there was a very loud hissing sound and, like Old Faithful, the steam put on a pretty good show. It went a good 15’ into the air before it started to fan out and move sideways. The cat was sleeping nearby and when the plug blew he jumped almost as high in the air as the steam had. The last I saw of him he was pawing his way through the air hoping to make it to the wood shed before losing altitude. He still shakes slightly when he sees the steam rising off his coffee in the morning. Or it could be time to switch to decaf.
I wasn’t able to repeat the experiment because the small rubber plug was probably in the one of the surrounding counties so I didn’t waste my time looking for it.
Actual Explosions With Pressure Cookers?
With my experiments done, I checked the Internet. You can see pressure cooker mishaps on YouTube, mostly in restaurants. In these cases, some were possibly old enough to lack modern safety valves and in all cases, the cooks were doing other things in a busy kitchen and not keeping a close eye to be sure the steam cap was still rocking. The few actual explosions were in restaurants but the majority of them were rapid steam releases, both completely unavoidable.
As with the restaurant pressure cookers, all of the home issues were due to leaving them unattended. Even if the other three rules are ignored, they can only become dangers when pressure cookers are left unattended and nobody notices the weight cap isn’t rocking, Had they done so, the heat could have been turned off, the pressure would have dropped immediately, and nothing dangerous could have happened.
As an important side note, one thing I was unable to test was how close someone has to be to a rapid steam release to be injured. The Ideal Gas Law also says that as gases expand, they rapidly cool down. Refrigeration works by compressing Freon, then letting it expand rapidly. As a young teenager I shot a nearly empty blow torch propane tank but instead of the fiery explosion I was hoping for, when I picked it up it was covered with frost due to the rapid propane gas expansion from its compressed state. Steam does the same thing. I don’t know the distance but I would guess that in a pressure-cooker steam blast, a person would have to be pretty close to it, or have a lot of food coming out with it, in order to be burned.
The stories I read online where the user received 1st and 2nd degree burns were both with regular pressure cookers as well as Instant Pots. The user was typically only a few inches from the steam and lifting the lid off. The pressure-cooker instruction booklet indicates that some recipes need a quick cool down after the burner is turned off. This is accomplished by manually tipping the steam cap sideways to slowly release the steam. If done incorrectly, large amounts of steam can be released very quickly and burn the user. On Instant Pot Q. & A. websites, almost all the replies in the comments sections said in the situation described by the questioner, each burn case was due to human error. After doing an incomplete pressure release, the users generally made the hazardous mistake of removing the lid from the pot even though they still felt resistance. Do some research on this topic.
The Safest Way to Use a Pressure Cooker
I’ll use black beans as an example of how to safely cook with a pressure cooker. After soaking overnight, the user manual says black beans should be cooked from 2-4 minutes depending on how firm you prefer cooked beans. I use three minutes. Remember, this is the total cooking time once the steam cap starts rocking.
The user manual says to soak the beans overnight, then 1.) rinse well before putting in the cooker, 2.) fill it no more than half full, 3.) add water until the beans are just barely covered, and 4.) add a tablespoon of vegetable oil. These four things keep foaming to a minimum to prevent potential steam-vent clogs.
After putting the lid on and the pressure cap in place, I turn the burner on high. Depending on the pressure-cooker size and amount of beans and water, the pressure cooker should be up to pressure in 10-20 minutes. The metal safety button in the handle pops up so I know it’s almost to full pressure. Before the cap starts rocking, a little steam may come out from the safety plug, the metal safety button, and from under the lid as the pressure cooker is getting up to full steam. After 2½ – 3 minutes, everything seals up and the pressure cap starts rocking. When it does, I start the timer and turn the heat down so the cap is rocking gently. I stand there for those three minutes while the beans are cooking, watching the cap rock back and forth indicating the steam vent isn’t clogged. As long as it’s rocking, all is well. In all the years that I’ve used a pressure cooker, I’ve never had it clog. When the three minutes are up, I turn off the heat. The cap stops rocking and the pressure begins dropping immediately.
For beans, the user manual says to allow the pressure cooker to cool until the metal safety button in the handle has dropped down, allowing the lid to be removed. This generally takes 30 minutes or so. Before opening the lid, just as an extra precaution I “burp” the pressure cooker by tipping the cap to one side. Then I remove it and open the pressure cooker. If I’m making a small batch of chili, I make it right in the lidless pressure cooker.
It’s that simple. After a few batches, a newcomer to pressure cooking will get used to the procedure and realize that as long as steam is coming out from beneath the weight, pressure will remain in the perfect range, much too low to engage the safety valve or blow out the rubber safety plug.
There are slightly different styles of pressure cookers so it’s important to follow the directions in the user manual even if we don’t understand the reasons for each item. Also, some foods can be filled more than half full so follow the user manual instructions. Generally, online pressure-cooker recipes will also mention the safe-fill level.
Things I No Longer Worry About
Before running these four experiments, I used to worry about forgetting to turn the heat down, bumping the cap while it was rocking, knocking the pressure cooker off the stove, and doing whatever it was to cause the safety plug to blow. Now, I rest easy when using my pressure cookers. I wish I had done these experiments years ago instead of just thinking about it from time-to-time.
If I forget to turn down the heat once the cooker is up to pressure, I know excess steam from high heat can’t blow the cap off the steam vent.
If I bump the cap, I know the tabs will keep the cap from coming off. It may tilt to one side and release steam but with a hot pad or something nearby, I can quickly tip it back into the correct position.
If I knock the pressure cooker off the stove, the pressure cap will catch on the steam vent to control the rate of steam being released. While it can still be enough to cause 1st or 2nd degree burns, I know instead of following the natural inclination to watch a falling object I need to get out of the way as quickly as possible. I also keep my pressure cooker on the back burner with the handle facing sideways to make it nearly impossible to fall off the stove while cooking.
I know I need to replace any gaskets with the slightest issues. The same protocols used when putting lids on canning jars should be used with pressure cookers: be sure the rim of the pot is clean of debris, be sure both sides of the gasket are free of debris, and be sure the gasket passes a visual inspection looking for cracks, rips, etc. I also know that I need to be sure the safety plug hasn’t hardened.
Pressure cooking is now less stressful. And even if I break three of the four important rules (which I’d never do), as long as I’m standing there attending the pressure cooker and shut off the heat if the cap stops rocking, I’ll prevent anything dangerous from happening. I now leave my PF Flyers in the closet when I’m using my pressure cookers.
The Take-Home Message of This Article
A pressure cooker will be an indispensable TEOTWAWKI item. If you don’t already own one because you’re afraid of the potential dangers, follow these five rules and your pressure cooker will be as safe to use as your waffle iron.
1. Clean and check the pressure cooker before using. Check the gasket and the steam vent.
2. Keep the steam vent clear – Let me repeat for the final time the most important concept: the only real way for a pressure cooker to become a danger is for the steam vent to get clogged. Check it before using the cooker, then be sure to strictly observe the maximum fill levels for each recipe. In a tiny minority of cases, if a lid gasket is in bad enough shape it could possibly blow out once the cooker is up to pressure, but generally the cooker won’t pressure-up to begin with if there are gasket issues.
3. Keep an eye on the pressure cooker to be sure the weighted cap is rocking or spinning. If it stops, turn off the burner.
4. Follow the manufacturer’s directions on cooking different kinds of food – Most importantly, how full to fill the pressure cooker. The user manual will have charts showing times for basic foods like beans, rice, pasta, meats, etc. A few call for covering with tin foil to prevent splashing.
5. Start out easy with quick-cooking food – These range from 1-5 minutes and include among others, dry beans, vegetables, and recipes with small pieces of chicken or other meat. If you never get past these, you’ll be in good company with the majority who never feel a need to move beyond these which cook quickly and are easy to keep an eye on.
In closing, I used my first pressure cooker strictly for beans the first ten years I had it. If that’s all we ever use it for in TEOTWAWKI-ville, it’ll create huge fuel savings. For those who have a pressure cooker but are afraid to use it, follow the instructions in your user manual and cook some dry beans to build up your confidence. Or have your spouse do it while you rush out to that emergency pinochle game. For those who still don’t own a pressure cooker, go ahead and buy one and start getting accustomed to it before the SHTF.
For those hard-core preppers planning for the worst, many foods that you want to home may only be pressure canned once refrigeration becomes a faded memory. You’ll need some way to can all those potatoes, meats, poultry, chilis, and soup stocks, among many other things. Learning to use a smaller pressure cooker is a good way to prepare for using a pressure canner if you don’t already own one.