Mold doesn’t sound very appetizing. But mold is involved in the making of so many foods we enjoy; from baked goods to aged steaks. Mold is a crucial part of the fermenting process-hello wine and cheese! It has also been used for centuries to make Shio Koji-an essential Japanese seasoning. Made from rice that is inoculated with Aspergillus oryzae, Shio Koji has a mild and sweet flavor that is the basis of miso paste and one of the most versatile ingredients in a Japanese kitchen.

Shio Koji can be used as a marinade to both tenderize and flavor meats, as part of a sauce, or as a replacement for salt. Although it takes about a week to make, the process is almost completely hands off. With the Shio Koji, we are going to make some pickles, which are essential to a traditional Japanese meal. It’s really quick and easy to make, and the perfect way to highlight the use of Shio Koji.

Making Shio Koji

If you live in a big city with a large Asian population, you can probably find commercially prepared Shio Koji at a well stocked Asian grocer. I haven’t had any luck finding it in Miami, though I did find some while visiting my daughter who has an H Mart (the Asian super store) nearby.

But Shio Koji is very simple to make from scratch and a wonderful ingredient to have on hand. You will need to buy Koji rice; I got mine from Amazon. There are a couple different strains of the Koji culture. The rice I got was snow white but I’ve also seen it a darker color.

The fermentation process is helped by massaging the rice, so do it for several minutes. Next we put the mixture into a container and allow it to ferment for about 10 days-a couple days less in the summer where it will ferment more quickly, and a couple days more in the winter when the temperature in your house drops. I put the container in a cabinet so it’s out of the way, but make sure you don’t forget about it. Stir the contents gently with a clean spoon every couple of days. You will notice the mixture getting thicker as the days go by and you should notice a sweet smell as well.

Once the koji is ready, store it in the fridge. It will last for up to 6 months. Use a spoonful whenever you want to add a pop of umami to a dish. It’s also popular to marinate meats, like chicken or pork, with Shio Koji. Coat the meat with a couple tablespoons per piece and marinate overnight for the best flavor. Or, use it to make pickles!

Shio Koji Pickles

Pickles hold a very elevated spot in Japanese food culture. There is hardly a meal that doesn’t have a little bowl of some type of pickled vegetables. Sometimes pickles are the main event, served simply with some steamed rice. They are wonderful starters, as they enhance appetites. Served as a side, they offer a bright balance to a heavier meal. There are many different styles of Japanese pickles, like this quick Daikon pickle. Those made with Shio Koji are called shiokojizuke, and any kind of vegetable can be pickled in this style.

No matter what type of pickle is enjoyed, they all offer outstanding health benefits from the probiotics and enzymes. Pickles are great for digestion and full of micronutrients. For this very quick pickle dish, I’m using cucumbers, carrots, and radishes for a variety of colors and textures. Some other vegetables to consider for this pickle include daikon radish, green cabbage, or even chayote squash.

I start by cleaning and trimming the veggies. Other than maybe cutting the vegetables in half to fit your container, there’s really no other prep.

At this point I let the pickles sit on the counter for a couple hours, and then I put them in the fridge for at least four hours, or ideally overnight. They will get saltier, and more pickle-ier (yes I just made up a word) the longer they sit. You can rinse the koji off or leave it on. I prefer the little specks of white on the colorful veggies, but it’s totally up to you. (Once the vegetables are done pickling, you can pull them out of the marinade, rinse them off, and store them in a different container to keep them from continuing to absorb the marinade. They will keep for several days.)

I generally do not throw out the used marinade. Instead, I will do a couple more batches of veggies, increasing the marinating time as the koji gets watered down with each batch. Make sure you use clean utensils when digging into your container as you do not want to introduce any bacteria that will create spoilage.

I love to eat these crunchy pickles as is, but they are also excellent anywhere you enjoy pickles. These pickles do not have a strong flavor so they are incredibly versatile and would make a great addition to any number of meals: on sandwiches, to add some zip to a salad, a welcome side to grilled fish, as part of a charcuterie platter…how will you serve them? Let us know by leaving a comment below, or tagging us in your pics @funkyasiankitchen, we love hearing from you!

Shio Koji

• Author: Funky Asian Kitchen
• Prep Time: 30 minutes
• Total Time: 30 minutes
• Yield: serves 6 1x
• Category: small plates
• Cuisine: Japanese

Print Recipe

Pin Recipe

---

Ingredients

Scale 1x2x3x

For the Shio Koji:

• 10 oz dry rice koji (300 g)
• ¼ cup sea salt (60 g)
• 16 ounces water (473 g)*

For Pickles:

• 6 red radishes
• 2 small persian cucumbers
• 1 medium carrot
• 1 cup prepared shio koji
• 1 teaspoon sugar
• 2 whole dried chilies
• 2 large garlic cloves smashed
• 1 square kombu, cut into 4 pieces

---

Instructions

Make the Shio Koji:

1. Put the rice in a bowl and use your hands to break up the rice into small pieces.
2. Add the salt and continue massaging the rice for about 2 minutes.
3. Add half of the water and continue squeezing and massaging the rice for another 2 minutes.
4. Add the remaining water and stir. 
5. Pour the mixture into a container and cover with a lid. Store the container in the warmest part of your kitchen. (I put mine in a cabinet near the stove.)
6. Let the mixture ferment for approximately 10 days. Mix the contents with a spoon every couple of days.
7. The shio koji is ready to use when the mixture is thickened and there is a gentle sweet scent. Store the shio koji in the fridge until ready to use.

For the Pickles:

1. Wash all of the vegetables. Trim and peel the carrots. Trim the cucumbers and the radishes.
2. Fit the vegetables into a tight shallow container. 
3. (You can also use a gallon zip top plastic bag.)
4. Add the smashed garlic, kombu, and dried chilies on top of the vegetables. 
5. Mix the sugar and the shio koji together until the sugar is dissolved.
6. Pour the mixture over the vegetables. Place the lid on top of the container. If using the bag, push all of the air out of the bag and zip it closed.
7. Leave the container out on the counter for a couple hours then place in the refrigerator.
8. Refrigerate the vegetables at least 4 hours or overnight. The vegetables will continue to get saltier as they marinate. The veggies are ready to eat after the first day.
9. You can rinse the koji off before eating or eat it without rinsing.
10. Once the vegetables are pickled to your liking, you can take it out of the brine, rinse it off and store it until ready to eat. The vegetables keep for a week refrigerated.

---

Notes

* Avoid hard water or alkaline water and do not use rock or kosher salt.

*I reuse the marinade a couple of times, increasing the pickling time to adjust for the decreasing saltiness. 

Keywords: shio koji, japanese pickles, fermented foods, asian condiments