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Ultrasonic Chef's Knife

seattleultrasonics.com

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Re: Ultrasonic Chef's Knife

#561

Post by peteforde »

com2kid wrote: post #375
peteforde wrote: post #336

I recently backed NeoBlade, which is an ultrasonic multi-blade cutting device for crafters. https://www.kickstarter.com/projects/hozodesign/neoblade TL;DR it's really freaking cool, though the blades do seem to get dull fairly quickly. That said, they are made of a radically different grade of steel. If the tech in the NeoBlade has been adapted successfully to the chef's knife, then all of the haters are going to sou…

I'm still in the camp that air fryers are stupid. A convection oven does literally the same thing. Also, portable air fryers make such small servings that they're useless for people with families. What the hell I going to do with three chicken wings?

You're technically right that an air fryer is a type of small convection oven, but dismissing them as "stupid" ignores why they're so popular. The point isn't that they reinvent physics, it's that they package convection in a way that's faster, uses way less electricity, is easier to clean, and perfectly sized for 1-2 people. Most folks aren't cooking for a big family every meal. I often just want to make fries, roast veggies, or crisp up leftovers. My Cosori lets me do that without heating the entire kitchen (and way faster, too).

I also simply don't have a convention oven. I rent my place, and it's not like I can just swap out the white goods.

Yes, the smallest ones are limited in capacity, but that's not the whole category. Larger models handle whole chickens.

The proof is in the market: people buy them in droves because they make food hot/crispy really quickly. A conventional oven can do the same thing, but it's like saying a desktop computer makes laptops "stupid". Technically true, but it ignores convenience, size, and efficiency, which are the reasons air fryers took off.

Anecdotally, most air fryers are owned by people who used to believe that they didn't need an air fryer. Have you actually had one in your life?

Re: Ultrasonic Chef's Knife

#562

Post by balls187 »

herpdyderp wrote: post #552
dlcarrier wrote: post #352

Earlier quoted context omitted.

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

I've tried sharpening knives a few times in my life and I've never been able to tell the difference. I agree with the principle, but in practice I simply haven't witnessed it matter.

It matters most for two things: safety and efficiency.

Unsharp knives cut well enough, and I would assume that people's knife skills and/or cooking skills may not notice the difference.

Do you follow a mise en place approach to cooking?

Re: Ultrasonic Chef's Knife

#563

Post by amluto »

lightedman wrote: post #546
hn_go_brrrrr wrote: post #537

Earlier quoted context omitted.

Cutting garlic or meat will both require more cleaning than just a rinse.

You're supposed to keep a glass of water with a bit of chlorine bleach (to obtain roughly 300 ppm) handy for wiping your tools and surfaces down as you work. Not that anyone teaches Home Economics at school any longer.

Taking a piece of metal or a plate that has any oily or other non-water-soluble food on it, rinsing it, and chlorinating it results in a mess that might indeed be non-infectious but is otherwise disgusting. Also, leaving a piece of stainless steel covered in chloride (which that bleach will turn into) is one of the worst things you could credibly do to it in a kitchen context. (And, while the relevant regulators don’t seem to care about disinfection byproducts in a kitchen, all those residual organics that didn’t get removed plus hypochlorous acid seem like they would thoroughly fail most drinking water standards.)

Also, I don’t know what all the food safety and dishwasher vendors are telling their customers, but that nice residual chlorine has a tasty and odor that is not appetizing at all. But you can also legally disinfect your dishes and such with sufficiently hot water, and you can buy a commercial dishwasher that does that instead of using chlorine.

In a home context, what’s wrong with dish soap and a sponge or brush? In a commercial kitchen that really wants to be compliant could use dish soap followed by a (very) hot rinse. The average household instant hot water tap is plenty hot for this, too, although demonstrably hitting those HACCP targets might be tricky.

Re: Ultrasonic Chef's Knife

#564

Post by fernandotakai »

kleiba wrote: post #556
idiotsecant wrote: post #553

Earlier quoted context omitted.

I think you might be bad at sharpening knives. There is no shame in that, almost everyone is very bad at it, it's difficult to do it properly.

> almost everyone is very bad at it [citation needed] It's more that sharpening a knife - like many other skills - takes practice.

most people don't even know how to properly hone a knife since there are specific movements.

i would recommend anyone sending their knives to a professional for sharpening -- you will feel much more confident cutting, and everything will be safer.

Re: Ultrasonic Chef's Knife

#565

Post by amluto »

tptacek wrote: post #400
CamperBob2 wrote: post #390

Earlier quoted context omitted.

For those of us who aren't knowledgeable in this field, what happens if you do?

It's hard to do irreparable damage to the steel of a knife. It's just an inert lump of metal. But you could fuck up the handle. Theoretically, the detergent could dull your edge. If you don't isolate your knife and it rattles around, that'll definitely dull it. Mostly: it should only take a couple seconds to clean off your knife in the sink.

> It's hard to do irreparable damage to the steel of a knife.

It’s easy — just heat it above the tempering temperature of the steel in question. You can achieve this in an ordinary oven for most steels, and you can also achieve it (locally) with a motorized sharpener that isn’t cooled. Don’t take a knife you care about to be professionally sharpened by a person who uses a non-water-cooled power tool.

Re: Ultrasonic Chef's Knife

#566

Post by balls187 »

Saline9515 wrote: post #526
athoscouto wrote: post #508

Earlier quoted context omitted.

I've seen chefs arguing the other way around. You have to apply more pressure when using duller knives, this means less control and less safety.

I agree, but this is more about stopping when you get hurt. I cook everyday and hurt myself only with very sharp knifes as I couldn't feel when the knife was about to cut my skin.

That's an issue of skill and technique.

For trained chefs, the sharper blade means things stay in place as expected, because the weight and motion of the blade are cutting, and not force exerted.

Related: I watch chefs use a mandolin, no freaking way I'd use it the way they do. I just do not have the skills necessary to free hand it. I will use a safety glove and/or a guard.

Re: Ultrasonic Chef's Knife

#567

Post by nathan_compton »

dlcarrier wrote: post #352
Taek wrote: post #243

I'm a bit surprised to see how much snark there is in the comment sections of this video. The requests for "let's see an independent chef use this knife to do real kitchen work" make total sense, but the moralizing around e-waste and losing fingers etc feels off balance. People spend hundreds of dollars and many hours sharpening kitchen knives, of course there's a viable market for sharper kitchen knives. And for e-w…

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

This seems like a sign that going into business selling knives based on their sharpness or apparent sharpness is a bad idea.

Re: Ultrasonic Chef's Knife

#568

Post by [deleted] »

peteforde wrote: post #561
com2kid wrote: post #375

Earlier quoted context omitted.

I'm still in the camp that air fryers are stupid. A convection oven does literally the same thing. Also, portable air fryers make such small servings that they're useless for people with families. What the hell I going to do with three chicken wings?

You're technically right that an air fryer is a type of small convection oven, but dismissing them as "stupid" ignores why they're so popular. The point isn't that they reinvent physics, it's that they package convection in a way that's faster, uses way less electricity, is easier to clean, and perfectly sized for 1-2 people. Most folks aren't cooking for a big family every meal. I often just want to make fries, roas…

[deleted]

Re: Ultrasonic Chef's Knife

#569

Post by bfdm »

rkomorn wrote: post #528
IanCal wrote: post #524

Earlier quoted context omitted.

People say this a lot but the dull knives I have won’t cut my hands around the force required to cut, say, veg. My sharp knife will cut my hand at extremely low levels of force. Also the direction the dull knives can slip is usually along the surface of what I’m cutting which would almost always be away from my hand.

I guess it depends on how dull your dull is. The knives I consider dull will absolutely cut me if I do something dumb, and I'm much less likely to do something dumb when the blade goes straight through what I'm cutting without having to use any force. I guess it also depends how and what you're cutting. I sure wouldn't try to julienne carrots with a knife that doesn't easily slice through the carrot.

The telltale sign for me is that chopping an onion causes the layers to separate from pressure before the knife starts to cut in. Super dangerous.

Re: Ultrasonic Chef's Knife

#570

Post by Retric »

mapt wrote: post #555
an_ko wrote: post #464

Earlier quoted context omitted.

Such people should perhaps consider a ceramic-bladed knife. They stay sharp basically forever because the blade is extremely hard, with the downside that it's not repairable with ordinary equipment if chipped. But if the owner would never maintain their metal knife anyway, then it's not _really_ a downside.

They do not stay sharp. On hard material and when overloaded, they will chip in large, unfixable chunks. On softer material, they continuously sharpen their edges at a microscopic scale, fracturing away tiny chips as they're worn, to new glassy ceramic molecular edges. A well used ceramic blade becomes micro-serrated. This sounds fantastic until you think about what is happening to the shards of hard glassy ceramic w…

People can work up to eating fairly large shards of glass. Eating tiny bits of ceramic occasionally are unlikely to be an actual issue any more than ingesting a little bit of sand.
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