Inverter microwave

[Auspicious]

Originally Posted by mikedefieslife

A typical 1000w microwave draws around 1500 watts. If you set the microwave power to 600w, the unit still draws 1500watts but cycles on and off more.

Which is what I said. Total power consumption is similar (I said the same) but peak loads are higher on conventional microwaves.

I did some Googling and found no numbers outside of marketing pieces to substantiate the claimed 15% total power reduction of inverter microwaves. There are some credible sources of reviews (more than advertising mills) that don't talk about power efficiency.

Originally Posted by mikedefieslife

I've not run any tests as I have better things to do in life (like fix all the broken things on my boat , but I would think that when I need to reduce the heat source, actually doing so and having a constant stream of 30 or 50% heat, is preferable to heating at full power for 30-50% of the time. That's how you burn the outside of your food but fail to cook the inside well.

Incorrect. You are considering the microwave as if heat impinges from outside the food. It doesn't. The microwaves cause the molecules in the food to vibrate; vibrating molecules generate heat. The extent to which surfaces heat faster is due to the attenuation of the 2.45 GHz microwave radio inside the food. The molecules vibrate faster near the surface of the food than near the center. Temperature does equalize due to conduction. Thermal inertia applies. The difference in cooking efficacy, if any, favors the intermittant cycling in most use cases.

Again, no credible source material including from professional or academic source that cites improvements in cooking quality from inverter microwaves.

It would seem to me that one of the benefits of inverter microwaves is lower appliance weight which makes it easier to tie them down properly so they won't go flying across the cabin in a seaway.

[GordMay]

Cooking food (successfully) in a conventional (power transformer) microwave is challenging because the magnetron, the element that cooks the food in most microwaves, can only deliver full power. Even when set to “50% power”, the microwave oven is actually going through cycles of delivering 100% power, followed by a period of no power.
In an inverter microwave oven, the power level of the oven can be adjusted as per the heating load. So when you set 50% power, for example, you actually get a steady stream of 50% power for the entire cooking time.

The result is lower peak demand, more evenly cooked food, defrosting without cooked edges, and even the ability to keep foods warm until mealtime.

[Auspicious]

Originally Posted by GordMay

Cooking food (successfully) in a conventional (power transformer) microwave is challenging because the magnetron, the element that cooks the food in most microwaves, can only deliver full power. Even when set to “50% power”, the microwave oven is actually going through cycles of delivering 100% power, followed by a period of no power.

On microwaves I have used the power cycle is five or six cycles per minute.

Your observation neglects thermal inertia, attenuation effects from surface to center of food, and conduction as a function of time.

If the factors don't convince you I offer the analogy of making Hollandaise sauce moving the pot on and off the heat specifically in order to maintain stable temperature so the eggs don't cook and the emulsion does not break.

I take exception to your statement that cooking in a microwave is challenging due to power cycling. "Cooking" in a microwave is challenging because browning doesn't happen. Fine for reheating and for things like baked potatoes. Not useful for a decent steak or even a mediocre hamburger. Can't make a decent chicken breast. I guess you could make enchiladas if you hit them with a propane torch to brown the top.

First person to cite Maillard reaction gets keel hauled. *grin*

sail fast and eat well, dave

[CaptTom]

I use a cheap-o WalMart 750W microwave. Not a dial type; it has a digital display and pushbuttons. Not an inverter type. It works fine on the 2,000W inverter, although we think it's a bit slower and makes a slightly different sound. Seems a lot cheaper than getting an inverter type 1250W microwave and running it at half power or 60% power. And if it dies I'll just buy another.

A word of caution to those looking at inverter microwaves: They operate at about the same frequency as a WiFi router, and can case significant interference. Without the long, boring story about how I spent weeks tracking down an intermittent network problem which seemed to always interrupt our lunch break, suffice it to say I have first-hand knowledge of this fact.

[Auspicious]

Originally Posted by CaptTom

A word of caution to those looking at inverter microwaves: They operate at about the same frequency as a WiFi router, and can case significant interference. Without the long, boring story about how I spent weeks tracking down an intermittent network problem which seemed to always interrupt our lunch break, suffice it to say I have first-hand knowledge of this fact.

Lots of things share the ISM band and intermodulation can lead to interference: microwaves, WiFi, Bluetooth, GPS, satellite phones.

[LostBiker]

Getting back to microwaves, over the road truckers use 12v microwaves. There seems to be quite a selection -

12 Volt Microwave For Truckers – BestMicrowave


John

[GordMay]

Originally Posted by Auspicious

On microwaves I have used the power cycle is five or six cycles per minute.

Your observation (#17) neglects thermal inertia, attenuation effects from surface to center of food, and conduction as a function of time.

If the factors don't convince you I offer the analogy of making Hollandaise sauce moving the pot on and off the heat specifically in order to maintain stable temperature so the eggs don't cook and the emulsion does not break.

I take exception to your statement that cooking in a microwave is challenging due to power cycling. "Cooking" in a microwave is challenging because browning doesn't happen. Fine for reheating and for things like baked potatoes. Not useful for a decent steak or even a mediocre hamburger. Can't make a decent chicken breast. I guess you could make enchiladas if you hit them with a propane torch to brown the top.

First person to cite Maillard reaction gets keel hauled. *grin*

sail fast and eat well, dave

Points taken.


However, since YOU mentioned it:
“Food Processing and Maillard Reaction Products: Effect on Human Health and Nutrition” ~ Nahid Tamanna, and Niaz Mahmood
➥ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4745522/

[Auspicious]

Originally Posted by LostBiker

Getting back to microwaves, over the road truckers use 12v microwaves. There seems to be quite a selection -

Hello John.

The microwave you linked--representative of many 12 VDC applicances--is very problematic. Even a "low power" microwave will draw 70 amps. Inadequate installation, including insufficient battery capacity as well as wire size, is why many over the road (OTR) trucking companies explicity stop their company drivers from using such equipment in company trucks. Owner-operators of course can use what they like.

There are a number of cooking groups for OTR truckers. They tend to carbs and fats but still some good stuff with application to cruisers, especially those who find cooking a challenge.

Regardless, if you're going to carry a microwave my suggestion is to use an inverter close to your batteries with properly sized cabling between batteries and inverter and run AC to the microwave and other appliances. Never lose sight of the power you are pulling from your battery banks.

sail fast and eat well, dave

[JCA320]

Originally Posted by GILow

Yep, I have one, 1200 watt max.

It is just as the technical specs say, power level varies depending on the setting you use. This is backed up by my inverter (as in the one that converts dc to ac) and the power levels are about consistent with the readings I get from the inverter display.

The manual went on about how inverter microwaves cook things better. I don’t know about that since I have never cooked anything in a microwave, I just use them to defrost or reheat stuff.

It does seem to defrost things a little better (more even) than the old sort.

Do you mind sharing the brand/model number if you’re happy with it?

[Eder]

If I was on a boat that used a microwave to feed the crew I'd jump over board.

[CaptTom]

Originally Posted by Eder

If I was on a boat that used a microwave to feed the crew I'd jump over board.

On our boat, we ARE the crew. And we use the microwave a lot. We also use the range, the bread maker and especially the InstantPot. Each has its purpose. Being able to eat a warm meal underway without taking time out to do a lot of cooking, especially if conditions aren't ideal, is priceless.

I have crewed with owners and skippers who disliked canned or prepared foods. They also happened to be great cooks. The chow was good, but the time spent provisioning for and preparing meals added a lot of complexity to the logistics of each day and impacted the schedule (this was on deliveries.)

[Auspicious]

Originally Posted by CaptTom

On our boat, we ARE the crew. And we use the microwave a lot. We also use the range, the bread maker and especially the InstantPot.

If you're happy that's fine. The increasing dependence on appliances (including quite specifically the dreaded cult of Instant Pot) instead of skill is distressing.

Breadmakers? Really? Those things at the end of your arms are called hands.

Sure, making a lasagna from scratch halfway between Horta and Falmouth is really hard, but making lasagna before departure and freezing it is trivial. Hint: most lasagna recipes are for 9x13 pan - double that and make three 8x8s.

"Taking time out to cook" is a reflection, in my mind, of the political correctness in the 70s that led to the demise of Home Economics in schools and the rise of people who simple can't cook. It isn't hard. It is never too late to learn. Appliances are not a substitute for planning and preparation. If you think that provisioning for good food offshore adds to the complexity of logistics then I am very sad for you. You're losing a lot of flexibility.

Microwaves are fine for reheating, some defrosting (when you don't plan ahead properly), but NOT cooking. Being offshore is not an excuse for bad food. Let's not forget the lights and beeping of the microwave that intrude on the rest of the off-watch. That's not okay.

Now just get off my lawn.

[CaptTom]

Originally Posted by Auspicious

Now just get off my lawn.

LOL, OK, I can't really argue with most of what you say. Still, we do coastal cruising for enjoyment. We're not on a tight watch schedule, so no danger of waking the sleeping watch. Maybe the dog.

But I do have to say a couple of things in my defense.

If you make lasagna ahead of time, or cook a big meal with leftovers (sometimes in the IP), then even you acknowledge that the microwave is a perfectly legitimate way to reheat it.

The breadmaker is a big improvement over slinging flour all over the cabin, but beyond that, it allows us to start it up underway and go back to enjoying the cruise, knowing that we'll be the envy of the whole anchorage when we open the cabin doors and the smell of fresh bread wafes out.

As for the IP cult, yeah, I'm in that. We use it all the time to make rice. Again, we can start while still underway, and have it ready for supper. Another good one is called "one pot lasagna." Basically, throw everything in, press a button, and it's ready in like 20 minutes. Chicken comes out moist and tender. People even bake cakes and all kinds of crazy things in them.

Because of all these appliances, we eat much better than we otherwise would underway. You can only do so many peanut butter sandwiches, cans of pasta or pop tarts before you start craving real food.

[Auspicious]

Originally Posted by CaptTom

But I do have to say a couple of things in my defense.

I think this is a discussion so there is no need to mount a defense. You're wrong, but you don't need to defend yourself! *grin*

I have a warped sense of humor (or humour, depending on which side of the Atlantic I happen to be on at the moment). Please bear with me.

Microwave ovens and their kin are certainly convenient. "Legitimate" is a big word with judgmental overtones. Since you raised my lasagna (okay I brought it up, but still), I'll point out that many foods like said lasagna suffer by reheating in a microwave. Pasta in general tends to dry out. A covered skillet, obviously on a gimballed cooker, with just a bit of water does a better job in only a little more time. This works for things like stuffed shells as well. Dishes with less structural integrity like spaghetti take a little more attention but return good rewards. Now if you bought your lasagna in the frozen food aisle it may not merit such concern. MINE is worth some care. *grin* What then is the threshold for "legitimate?"

I'd say the same about foods like soups. If "soup" means Campbells or Progresso than sure, shove it in the microwave. If you put heart and soul into it then warming it gently on the cooktop, perhaps with additional water or stock, is a worthwhile endeavor.

Now I'm not much of a coffee drinker but some people are down right religious on that subject. If you sip at your coffee over time I suggest the Contigo West Loop (https://www.amazon.com/Contigo-AUTOS.../dp/B00HZI5XNO), which comes in an array of colors. You can drop kick one across the boat without a leak or a drip. For large consumers I like having a vacuum thermos like the ones you see in conference rooms. We carry two on Auspicious - one for hot drinks and one for soup. You don't have to reheat what doesn't get cold. I am a passagemaker so lights and beeps are disruptive to the off watch. That is my mind set. Boat motion is also an issue. In all my deliveries I've seen exactly one gimballed microwave, and that didn't work very well due to door weight.

You raised the issue of leftovers. I'm a big fan of leftovers. If I make a roast pork loin (say triple butterflied and stuffed with onion bechamel and spinach) with roast veg. I am going to make a lot. For a crew of four I'll make three or four pounds of pork. First round of leftovers are sliced thin for sandwiches. Next round might be shredded with a jar of sauce (I admit to cheating) for "barbecue." I'll do similarly with chicken, where grilled breasts turn into chicken tacos and then chicken salad and perhaps even a chicken Caeser. The microwave just doesn't help there.

I can simmer a leftover soup or stew on a gimballed cooker for the night watches without worrying about spills. Microwave? Not so much.

I have colleagues in the delivery business who do their provisioning entirely in the frozen food aisle. A microwave is key to their plan. It certainly isn't cooking. One skipper whose name you would likely recognize but I won't call out met up with me in Tortola some years ago and we had a joint crew dinner at the late, lamented Spaghetti Junction in Road Town. Our crews of course discussed their experiences coming down. The other boat was moving on to St. Martin and we were cleaning and offloading. In exchange for our leftovers I didn't buy a drink in the next two days as we packed out. *grin* I feel very strongly about eating well.

I am a big fan of pressure cookers. I carry two on my own boat (a 16 qt Presto and a 5l Kuhn-Rikon). They are worth the space. The Instant Pot is a poor pressure cooker. No worse than other electric pressure cookers but no better and significantly worse than conventional stove-top pressure cookers. This, Padawan, is why there are special cookbooks for electric pressure cookers.

I cook with what I have on boats. I can talk about the failings of IPs and other electronic cookery for slow cooking, rice, and yogurt for a long time.

To proceed, why are you slinging flour all over the cabin to make bread? You make the dough in an oiled bowl, knead it either in the bowl or on a lightly dusted counter, let it rise in the bowl. Why sling flour about? I'd rather clean a big bowl that I also use for salad or perhaps to chill beer in ice for an impromptu get together than have another single-purpose appliance to take up space and clean. Besides, the loaves look funny.

I absolutely agree with you about the smell of baking bread. Whenever I can (mostly) we bake approaching landfall. When C&I comes on board the boat smells nice, we have something to offer, and the relationship pays off greatly. On one trip I was fortunate to have two other cooks on board and when weather and a poorly maintained boat led to a long tow from USCG we had bread, cookies, and brownies for USCG, marina staff, and CBP) when we got tied up in Little Creek VA. No machines, no power, just hands. Well - a bowl and spoons.

I moved a boat into a major boat show for a broker and he hired me to stand on the boat and greet people. I made up a bunch of dough at home and baked bread and chocolate chip cookies during the show. We had a line to get on an admittedly worn boat. They had a small bidding war and a contract was signed by show end.

Originally Posted by CaptTom

Because of all these appliances, we eat much better than we otherwise would underway. You can only do so many peanut butter sandwiches, cans of pasta or pop tarts before you start craving real food.

Why? I could go on at great length about meal planning and provisioning, and have. Probably here. *grin* I've spoken at boat shows and rendezvous on a number of subjects but one of my favorites is "A Delivery Skipper Cooks." I certainly carry peanut butter. Canned pasta would never occur to me. Pop Tarts have been on the list when crew ask for them as a snack (snacks are another subject).

There is no more excuse for eating poorly underway than at anchor. Most power boats and sailing catamarans are admittedly more difficult than sailing monohulls but still eating well with the fundamentals is really quite simple. You don't need a bunch of appliances and I argue that most aren't labor saving. A stick blender is a major upgrade. Counter space is of more value than most other appliances. If you want to make an investment buy the biggest cutting board you can make fit over your gimballed cooker.

We've clearly landed on a hot button for me. Food is important. When we're getting ready for a trip we run around the crew on board before we leave, usually over a meal, to get to know each other (there are complexities here I won't get into). On one trip one of my repeat crew members (who actually had a list of things he wanted help with) said when his turn came up "I'm just here for the food." This is, by the way, an Alton Brown quote. I've been fortunate to have had a number of great teachers in my cooking life, from Jacques Pépin (who I don't know - YouTube) to Anja Drok who crewed for me fifteen years ago and pumped outstanding food out of the galley all across the Atlantic. As Chef Bernie Meehan, Executive Chef Emeritus of the Cosmos Club, taught me a good chef can cook anything anywhere. I have no pretensions of being a chef. I'm a damn good cook.

sail fast and eat well, dave

[Auspicious]

Now about my chicken marsala...

I crack myself up.