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Moritaka patina

Mon Sep 16, 2013 1:35 pm


A little while ago I bought a Moritaka Gyuto 240mm KG-240 Blue from you and I love the knife. The only thing is the upkeep. I am new to Chef's Knives and did some research before I bought my first knife the Moritaka. I read ll of the care info for the knife and other suggestions through forums but I can't seem to keep my blade from discoloring. I rinse it in between items with hot water and again with some soap and hot water when I am finished then I wrap it in a phone book to suck up any extra moisture. I looked at Sayas to see if that would help but it even seems like the blade starts discoloring right before my eyes while I am using it. I was wondering if there is a way to keep my knife in good condition and use it as my all around go to knife. I was also wondering if a different knife and steel may be better for all around use in the kitchen and maybe I should set my Moritaka aside for special use? I want to be able to cut different vegetables and fruits etc.. without worrying about running to the sink every second to keep the blade from discoloring? Any suggestions would be really appreciated. I hate to think I am not taking care of my knife, and hopefully knives, correctly.



Re: Moritaka patina

Mon Sep 16, 2013 1:46 pm

Hi Matt,

You're fighting an uphill battle my friend. Anyone that gets a carbon steel knife really has to accept that the knife is going to discolor. As a matter of fact it's encouraged, which is why lots of people force a patina on the whole blade to get it over with quickly. Patina on the blade will keep the steel from reacting with the foods you are cutting. That black patina is a layer of black oxidation that keeps acids from actually contacting the carbon steel. By constantly cleaning off the patina you keep the knife shinny but at full re-activity and the thing will discolor as soon as you look at it.

The Statue of Liberty is made out of copper and is blue/green but you can clean it and make it look like copper. The problem with this is patina will start forming on the exterior the minute you're done cleaning it and by the time you get to the end of the job the part you did at the beginning will be green again. They actually did this for some dumb reason a while ago with the expected results.

If you want a shinny knife get a stainless knife and you'll never have to worry about patina or stains again. There are lots of good ones around.

If you want to keep using the carbon blade and want to keep it shinny I would suggest oiling the knife after every use. The thin layer of oil (canola or olive oil is fine if you're using it daily) acts like a barrier and will help but not stop re-activity. My friend down the street owns a sushi bar and he keeps his carbon blade pretty shinny by wiping it with ice water and towel drying at his station after every use. It's tedious but it seems to work for him.

Re: Moritaka patina

Mon Sep 16, 2013 9:36 pm

MATT <> Stainless steel = no stains

Re: Moritaka patina

Tue Sep 17, 2013 5:56 am


Just force a patina, or let one develop (which is easier than what you've been doing up to now), and it should settle down.

It's also helpful to have a damp towel for wiping close to your board.

Re: Moritaka patina

Fri Sep 20, 2013 11:07 am

+1 on the CFTG, all carbon steel knives are going to do that. The patina on the steel is its protection. If you enjoy the performance of the carbon steel without the maintenance, or just want the knife to be "shiny" maybe you can look into some stainless clad knives where only the cutting edge is carbon steel.

Re: Moritaka patina

Sat Sep 21, 2013 4:48 pm

Thanks Everyone for chiming in. I am really most concerned with taking care of my knife. I don't really need it to stay shiny. I like a natural patina on things. I just wanted to make sure I was taking care of it properly. I will just continue to keep it clean and dry and let the patina build up. Just curious, now that I am looking for a patina on my knife, what I should do to encourage a nice patina?

Re: Moritaka patina

Sat Sep 21, 2013 4:53 pm


...and chefknivestogo wrote:

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