How to Ripen Kimchi
Everyone has a different preference as to when Kimchi(김치) tastes the best – some love eating freshly made, raw kimchi (kind of tastes like a salad); some love eating it when it is just perfectly ripe and then there are those who love sour kimchi (신김치 shin kimchi) which has basically over fermented and obviously tastes quite sour. But one thing is for sure – no one likes the stage when it is in the in-between stages of being raw and ripe. Kimchi really does not taste good at all when it is in the process of getting ripe – I had an aunt who used to call this the time when kimchi has gone CRAZY! And you certainly don’t want to eat the kimchi when it’s crazy! 🙂 So here’s how to ripen Kimchi and avoid CRAZY kimchi.
Since most of us now buy kimchi from the store, let me first write about the best way to eat a store bought kimchi. Too often, I hear people say that the kimchi served at our house tastes great, but when they try the same brand themselves, they think it doesn’t taste nearly as good. I realized it was because they don’t take the time to ripen it properly and then also forget to serve it cold (right out of the fridge). I found that most kimchi (even the poorly made ones) will taste quite palatable when they have had time to ripen properly.
Now, the hard part about buying kimchi from a store is that it is hard to tell at what stage of the fermentation process they are in. One clue is the appearance of the vegetables. They will look more shriveled up if they are further along in the fermentation process. And the chances are that it will also have lost a bit of the juice because the content will start to bubble and balloon up when it ferments which ends up usually overflowing out of the jar. This is actually too bad because kimchi should always be immersed in its own juices for it to taste the best.
The best way is to buy the freshest kimchi possible and bring it home and ripen it from the beginning. But this is usually not possible…So far, I have found the best tasting kimchi that you can buy are actually the ones that are directly imported from Korea (종가집Jongajip is my favorite). It is expensive but worth it in my opinion as long as it hasn’t traveled too far or stayed on the shelf too long at your store. Other than that, the next best thing is to try to buy kimchi that is made locally if it’s available (less chance of it over ripening) and when you bring it home, open it, smell it or better yet, taste it. If your store has a fast turnaround, it is probably in the “crazy” stage.
If it’s already fully ripe, put it in the fridge in the coldest possible setting. If it’s not yet fully ripened and you can wait, let it ripen in your fridge. This will take about 2 weeks in your fridge. Also note that the juice may overflow so either move the kimchi into a bigger container or take some out (1/5th) and leave some room for the kimchi to expand. If your kimchi is still very fresh, not at all ripe and you need to eat it quickly, you can ferment it at room temperature.
In the summer, Kimchi will ripen in 12 ~ 18 hrs and in cooler weather it can take about 24 – 48 hrs. Just check every 4-6 hrs.
If this is all too much info for you to digest, I have a chart at the bottom of this post that can help you with the process. (Boy, it’s been ages since I drew up a flowchart…brings back memories from my college days of hand drawing the charts using graphic rulers..)
What is the ultimate best way to ripen or ferment kimchi?
The most delicious and fantastic kimchi is made when it is fermented the old fashioned way…In a traditional Korean clay jar, buried in the ground in winter time. Even though the ground freezes in the winter, the jar and the saltiness of the kimchi keep it from freezing completely. This is called 김장김치 (kimjang kimchi). Kimjang kimchi is usually made around the ‘start of winter’ (입동 ipdong) in the lunar calendar which is just about now (Nov 7-8th in Gregorian calendar).
I remember when I was a kid, we spent days preparing and making kimjang kimchi so that it could last us through the winter and into spring. We first dug big holes in the ground big enough to hold our huge clay jars (so big that a child can fall in). In the meantime, we spent the day washing and brining 100+ napa cabbages and also preparing the ingredients for the stuffing. The next day we took these salted napa cabbages and inserted the stuffing in between each cabbage leaf. It was an enormous amount of work but boy…was it worth it. All winter long, we got to eat these amazingly crunchy and zingy and sometimes even ever so slightly frozen kimchi that came out of these jars in the ground. So why was it so tasty?
According to research, when it is buried in the ground, the temperature remains quite constant – at 32 – 35 F all winter long. At this temperature it takes about 20 days for the kimchi to fully ripen but it is definitely worth the wait.
The clay jars are glazed to hold the moisture in but it can still breathe which allows just the right amount of air circulation to take away any heat produced from the fermentation (keeping the temperature stable). It also keeps the air tight enough for the bacteria to not grow too fast which helps the kimchi maintain its peak flavor for a longer period. The history of kimchi can be dated back almost 2000 years to the Goguryo Dynasty according to some historians, so you can see how long Koreans had time to refine the technique of kimchi making.
Since most Koreans now live in apartments and have no backyards to bury the jars, they have invented what is called a kimchi refrigerator. This fridge is different from the conventional refrigerator because the interior walls of the fridge are cooled instead of the air which helps to keep the interior at a more constant temperature. I own one and I have to say it is the next best thing to having your own kimchi jar in the ground. It even has temperature options for fermenting and then just storing it to prolong its freshness.
How to tell if Kimchi is ripe and ready to eat?
When a kimchi is not fully ripe, you are able to smell and kind of taste the individual ingredients – garlic, cabbage, radish, green onion, fish sauce, etc – as they have yet to fully integrate with each other. When it is fully ripened, the tastes of all the ingredients are well blended together and there is full flavor embedded in each cabbage leaf or vegetable pieces. There is also a slight sour taste with an added zing at the end. You can also no longer smell the raw ingredients individually but rather have a combined, wonderful slightly stinky smell that is unique to kimchi. Below is the chart that I promised earlier –
So how long can I store Kimchi in the fridge?
When stored at the ideal temperature that’s close to the freezing point of 32 F (-1 to 0℃), kimchi will keep for 3 months or more.
If the temperature of your fridge is higher (which is normally the case), it will probably keep for at least a month or more. Kimchi will start to taste just too sour when it starts to go bad – at which point, the best way to eat them is by cooking them by making Kimchi Jjigae, Budae Jjigae, Kimchi soft tofu stew, Kimchi fried rice and of course Kimchi Mari! Kimchi will sometimes go bad – it will have this whitish kind of film when it has been really too long and will also smell very pungently sour. You don’t want to eat it at this stage.
Can I take my Kimchi out from the refrigerator and leave it on the counter again to ripen further?
YES! Whether you have store-bought kimchi or made your own kimchi, you can take Kimchi out of the refrigerator at any time and let it ripen or sour further.
If it’s not ripe enough, it will take a long time to ripen in the fridge.
The whole point about my flow chart above was for people who have store-bought Kimchi. You may think it’s ready to eat because you got it from the store, but many times they are not fully ripe and therefore doesn’t taste as good.
Well, I hope this was helpful. Please share this info so that more people can learn how to ripen Kimchi properly and enjoy it at its best!
Take care,
XOXO
JinJoo
PS – if you want to learn more about Kimjang, here are two posts that teach you all about it!
- Kimjang Day: Part 1- How it’s done – I share my experiences and tips learned while doing Kimjang with my mother-in-law.
- Kimjang Day: Part 2 – Ingredients and Tips
Mark lee says
Hi, I just came back from Seoul but after the flight back the whole packet bloated.. Is it normal? Have the kimchi spoil and wad should I do? Thanks in advance for the help..
JinJoo says
Hi! Yes, it’s totally normal for the packet to get bloated. The fermentation process makes the Kimchi expand! It’s not spoiled at all (unless you see yellow/whitish wet mold/cabbages turning to mush which I doubt over just a plane ride) It’s just ripening. It may have gotten a bit too sour for your taste though. If it has, Kimchi jjigae and fried rice is your best bet. Store it in the fridge in the packet (if it’s not leaking) or transfer the content to a glass jar or container. After transferring, push down the cabbages firmly to immerse them in the liquid as much as you can.
JinJoo says
Thanks for stopping by! Good luck!
Kaylee says
Hello I was wondering if you could help me? I bought kimchi at my local asian mart a couple of days ago and when I brought it home I notice the top wasn’t on tight! I wonder if my Kimchi is ok to eat? It had bubbles come to the surface but when I tasted it, it was fizzy tasting and I notice the leaves were pretty bitter. I’ve only had kimchi at restaurants and it was first time buying it. It didn’t have an expiration date and it doesn’t small bad either. So I don’t really know if it’s ok or not… any advice would help, thanks!
JinJoo says
Does it taste really bitter and sour? Was the kimchi immersed in the juice? The good thing is that Kimchi usually doesn’t go bad enough to make you sick – unless it’s so old and not properly stored that there are actual molds (kind of yellowish white wet mold) that appear on the kimchi itself. Then you should NOT eat it. Kimchi can also taste bitter and not good if it was not properly immersed in liquid (which I suspect may have happened since you said the top was open-the top probably came loose while it was fermenting and started overflowing and lost some juice) and not stored in the right temp or stored too long. It should never taste bitter and even tasting too sour is just not right for a store bought Kimchi. It should be either just ripened or not yet ripened when it is sold.
If it’s not a popular Korean market (with fast turnovers) my guess is that the Kimchi was probably stored too long. I think you can eat it but if it tastes really bitter and/or sour, I would recommend that you take it back to the store. Let me know if you have more questions! Good luck!! Thanks!
Ingrid says
I made kimchi last month and place it in a plastic lock n lock container. But until now it doesnt taste sour. It even taste bitter. And yesterday i did what you told, to place it in a room temp. But its still the sane. What to do?
JinJoo says
Hmm…kimchi can taste bitter for few reasons. It could most likely be because it is in the Crazy stage (just about to ripe) which means you just need to let it ripe. Give it another day at room temp – it should ripe as long as the temp. is not too cold. It could also be because of the salt you used. Koreans use a special kind of salt for kimchi – sea salt where the bittern (bitter tasting solution) has been removed. It could be that the salt you used could have the bitter taste to begin with. Try tasting the salt on its own and good salt should not taste bitter.
If you made your kimchi quite salty, it could take longer to ripe which could also be part of the problem for you. what kind of kimchi is it? If it’s radish, it could also be because of the radish – it could taste bitter sometimes. If it’s the salt, unfortunately there isn’t much you can do. Otherwise, letting it ripe is the best thing to do. Let me know if you have more questions! Good luck!
Jen says
Hello JinJoo,
Thank you for this very informative article! I love kimchi and have just tried making it at home. The recipe I used required one and half cups of salt for 2 large napa cabbages. However, after the soaking process the cabbage was very salty even asfter several times rinsing. So I threw that batch away and soaked another 2 large napa cabbages using 3/4 cup of salt instead for both cabbages.
I have stored my kimchi in glass jars in room temperature (22 degrees Celcius) for the fermentation process. It has been in the jars for about 2 days.
I have read on blogs of people who made their kimchi and have lots of bubbling in the fermentation process to the point where their jars sometimes explode, even by day 2.
At day 2 of being in the jars here are some things I noticed about my kimchi:
1) A lot more liquid in the jars
2) I can also see tiny bubbles inbetween the pieces of cabbage
3) When I put my ears to the jars I can hear a soft, slow ‘ticking’ sound
Since this is my first time making kimchi, I don’t know what to expect. Are any of the signs in points 1-3 an indication that my kimchi is fermenting? I have 5 hugs jars full and hope that I don’t have to throw it all away!
Looking forward to your reply!
Thanks so much!
JinJoo says
Hi Jen! The increased liquid and bubbles are definite signs that your kimchi is fermenting but perhaps taking longer than most. If it’s on the salty side, it can definitely take longer. Also the 22 C room temp is more on the cooler side so it will not ripe as quickly.
If you have 5 huge jars, I would suggest that you store most of it in the fridge soon so they will keep fresh longer. If I were you, I would leave one jar out at room temp until it fully ripens and keep the rest in the fridge. Don’t worry, it will ferment – prob. in another day or two. Just check everyday and make sure it doesn’t ripe too much!
Let me know how it goes. Good luck!
Jen says
Hi JinJoo,
Thanks for your reply and advice. Very glad to hear that my kimchi is fermenting, even if doing so slowly. When I opened one jar, I did hear a very soft fizz sound. I have tasted the kimchi. It still tastes a bit CRAZY…I can taste the strong paste flavour and seems like all the flavours have not integrated yet.
I have left one jar out on to ripen in the pantry and the other 4 jars are now in the fridge and will keep monitoring them.
C’mon kimchi ripen for me!
JinJoo says
The fizz sound def. indicates fermentation. And remember you can always take kimchi out from the fridge and let it ripe for a day or so if it hasn’t already.
Jennai says
Hi JinJoo,
Just a quick update to let you know that my kimichi which was fermenting quite slowly turned out perfect in the end! I was really pleased with the level of sourness and the taste. Thanks for your advice!
JinJoo says
I’m so glad that it turned out tasty! And thank you so much for letting me know. Enjoy!
Phillip C. Levatino says
Judith, send me your e-mail address mine is goongae@aol.com and I’ll send you the website for jjamppong. It looks spot on. We have a refrigerator in the basement that’s dedicated to Korean food but my beloved “little korean” keeps her “everday I need Kim Chi” supply in the refrigerator in the kitchen tainting my salamme, proscuitto, capacola and pecorino romano cheese. I love my “little koran” but I love my italian delicacies also. What’s a Sicilian to do?
itt
Phillip C. Levatino says
Jin-Joo:
A final question for tonight or actually, this morning. I’ve seen pictures of the brown Kim Chi jars but they were above ground. In fact the restaurant had dozens and dozens of jars ALL above ground. Doesn’t that defeat the purpose of burying the jars, i.e. to keep constant temperature around the jar
JinJoo says
Phillip, you are very correct. Kimchi jars should be buried in the ground. However, kimchi jars are also used to store other things like Dwenjang, Gochujang and Soy Sauce and much more. So probably the restaurant was using it for that. Thanks for asking!