Munetoshi care questions

[Crestwood23]

Got a nice birthday gift from my wife (heavily directed by KKF LOL) - a beautiful 240mm Munetoshi gyuto, a shapton glass 500, and a Hasegawa board. I am a newb and have some questions. I am loving the Munetoshi so far - such great balance and feel - WOW! Question- I cut a lemon and noticed some rust almost immediately - I scrubbed it down and removed the rust - is this a big no-no or am I ok with acidic foods as long as I clean and dry thoroughly?

I used the knife a few times and now have some difficulty cutting tomatoes - can I touch it up on the shapton 500 - or is it better to get a higher grit stone like a 2000 for touchups?

 

[HumbleHomeCook]

Congrats! That's an awesome gift.

Munetoshi have iron cladding so, as you're discovering, the entire blade is susceptible to rusting. You can cut anything you like with it. Yes, acidic foods will cause oxidation faster than other foods but that just means you need to rinse it sooner. You might find it discoloring onions at first as well. As you use your knife and it builds some patina, this will start to settle out and not be as aggressive.

Citrus can dull the shirogami faster but I don't shy away from it.

You can use the 500 to bring the edge back up but a higher grit stone is more appropriate for that task. I mean, don't suffer with a dull knife while you're waiting on another stone, but definitely plan to get one sooner rather than later.

A little laxative grade mineral oil can help with your handle and on the blade if you're concerned about it rusting at rest.

 

[NickMinton]

Just for clarification, you’re probably noticing patina as opposed to rust.

Depending on what foods you cut, the patina will be different colors. Hot Meats, especially pork and beef, usually make blades different shades of blues, mangoes too! Veggies and fruits will usually cause some yellows, oranges and purples but it’s always hard to predict

When you’re done with your knife, gently clean it with soap and hot water by hand. Hand dry it off and let it dry out in room air for a minute or two before putting a sheath, saya or cover on it.

Otherwise, go have fun. Munetoshi knives have a long history of positive reviews, so congrats and welcome!

 

[Crestwood23]

Congrats! That's an awesome gift.

Munetoshi have iron cladding so, as you're discovering, the entire blade is susceptible to rusting. You can cut anything you like with it. Yes, acidic foods will cause oxidation faster than other foods but that just means you need to rinse it sooner. You might find it discoloring onions at first as well. As you use your knife and it builds some patina, this will start to settle out and not be as aggressive.

Citrus can dull the shirogami faster but I don't shy away from it.

You can use the 500 to bring the edge back up but a higher grit stone is more appropriate for that task. I mean, don't suffer with a dull knife while you're waiting on another stone, but definitely plan to get one sooner rather than later.

A little laxative grade mineral oil can help with your handle and on the blade if you're concerned about it rusting at rest.

Thanks for the tips!

 

[noj]

Pretty much everything has been said, except perhaps patina is good for your food preparation. When a blade is first developing patina, you are (more) likely to notice it can add a metallic (iron) taste. The same thing happens if/after you remove it. Enjoy the patina - plus it can have pretty colors;-)

 

[JASinIL2006]

If you're impatient, you can force a patina using things like coffee or mustard; just search this board for terms like 'forced patina'. That can help avoid the imparting of a metallic taste to food while you wait for a patina to form naturally.

 

[aporigine]

… A little laxative grade mineral oil can

(fights to hold it in)
(the frivolous remark, also)

 

[aporigine]

Pretty much everything has been said, except perhaps patina is good for your food preparation. When a blade is first developing patina, you are (more) likely to notice it can add a metallic (iron) taste. The same thing happens if/after you remove it. Enjoy the patina - plus it can have pretty colors;-)

Once it stops discoloring shallot or red onion …

 

[M1k3]

Just keep using it and wiping it off. Eventually it'll act -nearly- stainless.

 

[M1k3]

When it starts looking like this, it's pretty stable.

 

[Benuser]

When it starts looking like this, it's pretty stable.View attachment 334626View attachment 334627

A bit how it looks after applying phosphoric acid, which enhances patina formation. Patina is the next oxidation of common rust. Very obvious when abundantly rinsing with the hottest water. Orange turning grey.

 

[M1k3]

A bit how it looks after applying phosphoric acid, which enhances patina formation. Patina is the next oxidation of common rust. Very obvious when abundantly rinsing with the hottest water. Orange turning grey.

No Coca-Cola around my knife, thank you.

 

[Benuser]

No Coca-Cola around my knife, thank you.

Had pure phosphoric acid in mind.