About R's KOSO

What is Koso?

KO・SO (酵素)
an enzyme, a ferment

“Koso drink | fermented drink using traditional Japanese methods, rich in prebiotic and probiotics. It is also simply called Koso.”

"Koso" is defined as an enzyme or a ferment in Japanese. Koso drink is a traditional enzyme drink created from vegetables, fruits, and plants, which provides abundant probiotics + prebiotics + postbiotics. Koso is popular among young Japanese women, juice cleansers, and individuals who attempt intermittent fasting. Koso has been a healthy and safe dietary supplement in Japan, dating back about 100 years.

Japan has a long history of making fermented foods, such as miso, soy sauce and sake. Fermented foods are essential ingredients in the dietary habits of Japanese people. In the past, it wasn't easy to locate enough ingredients to sustain a healthy diet due to the lack of nutrient-dense foods. When Koso was created, it provided many different types of essential nutrients, allowing people to improve their quality of life.

Advantages Of R's KOSO

R's KOSO is Japan's best-kept health cleansing secret. R's KOSO contains over 100 different fruits, vegetables, and plant-based ingredients. R's KOSO includes unique ingredients such as seaweeds and mushrooms. Seaweeds are one of nature's best dietary source of iodine, which has been proven to help support the thyroid gland. Plus, seaweed is a little known secret that helps Japanese women maintain such beautiful hair. Mushrooms possess many vital nutrients like β glucans, dietary fiber, mannans, as well as act as prebiotics to stimulate the growth of gut microbiota.

R's KOSO utilizes over ten different yeasts during the one-year fermentation process, including lactic acid bacteria, and koji, which is a Japanese cultural fungus. Additionally, R's KOSO contains probiotics, prebiotics, and postbiotics such as acetic acid. All these essential ingredients help improve gut health, which is closely linked to weight loss, skin health, and mental health. Also, it could be long-term solutions for bloated stomach and constipation.

How to make R's KOSO?


Natural 100+ fruits, vegetables, plants including mushrooms and seaweeds. All ingredients are from Japan.


Cut ingredients and put natural sugar in a well-balanced state. The component is extracted as an extract without using any water by osmotic pressure.


Add secret Lactic acid Bacteria, Yeast and, Koji for fermentation. There are many useful microorganisms.


All ingredients are fermented and aged for about 1-year by the cryogenic tank. Our factory has 70 years' experience to make Koso. The product is manufactured to exceptional standards by highly trained professionals. All ingredients comes from Japan.


Enhance gut health - our century-old traditional Japanese fermentation process provides a natural, plant-based, probiotic to support digestive health, skin radiance and, immune system.

Feeds your microbiome - rich in prebiotics and dietary fiber to feed the beneficial bacteria that reside in your gut and promote a healthy gut.

Better digestion - rich in probiotics and prebiotics to help you absorb more nutrients from the ingredients in the formula as well as the other foods you eat.

Healthy weight - Studies show taking prebiotic fiber caused positive changes in the gut microbiome, including increased levels of beneficial bacteria that are associated with a decrease in fat mass.

Antioxidant-rich - contain abundant functional ingredients, i.e., polyphenols, vitamin A, E, C. It gives your body a powerful shot of helping you neutralize toxins and promote healthy, clear skin, anti-aging.

Boost Immune system - our fermented superfood supplement made from 100+ vegetables and fruits, provides balanced nutrition, combining probiotics and prebiotics. The gut actually has about 70 percent of the body's immune cells. Taking balanced food is one of the big ideas to keep a healthy gut and boost immunity.


Serving size:2 tablespoons (30ml / 1oz) of R's KOSO mix with 1/2 cup water or sparkling water. 1 serving is calculated for Cleansing. It can be used 1/2 serving for daily enjoyment.

Storage:Refrigerate after opening and use within 4 weeks.

Methods:Try Koso Cleanse. 1 bottles is good for the following.

Methods Good For Suggested Use Recommended Duration

Breakfast Cleanse (every day)

2 weeks

1 serving

12 weeks

Breakfast Cleanse (4 Days/w)

4 weeks

1 serving

12 weeks

1-Day Cleanse

3-4 weeks

3-5 servings

12 weeks

3-Day Cleanse

1 program

3-5 servings

Every 2 months

Daily Enjoyment

2-4 weeks

1/2-1 servings

Every day (at least 12 weeks)


- 100+ INGREDIENTS - Vegetables, Fruits, Seaweeds, Mushrooms -

Leafy vegetable mix (cabbage, lettuce, asparagus, broccoli, rape blossoms, celery, cauliflower, spinach, chingensai, suiki, spring chrysanthemum, chisha, parsley, sprouts, perilla), Fruit vegetable mix (cucumber, winter melon, tomato, eggplant, pumpkin, bitter melon, watermelon, corn, okra, bell pepper), Root vegetable mix (daikon, turnip, ginger, uddo, yamato, yam, potato, sweet potato, carrot, lotus root, taro, burdock, lily root), Fruit mix (apple, quince, loquat, ume, strawberry, akebi, kumquat, apricot, sudachi, fig, mandarin orange, iyokan, kiwi, persimmon, peach, cherry, melon, grape, plum, pear), Brown sugar, crude sugar, malt sugar, galactooligosaccharide, sugar beet, glucose, ume extract, Bean mix (green beans, green peas, broad beans, soybeans, black soybeans, red beans), Mushroom mix (shiitake mushrooms, shimeji mushrooms, eringgi, jellyfish, maiko, enokitake) Cereal mix (black rice, brown rice, barley, bare wheat, red rice), Seaweed mix (kelp, wakame, aosa, hijiki, nori, mozuku, tengusa), Herb mix (dandelions, crimson, clover, aoki, jacobe, yukinoshita, kimihihiki, hinata taikochichi, sugiina, itadori, seri, artemisia, persimmon leaves, pine leaves, cedar leaves, persimmon leaves, octopus leaves, mulberry leaves), koji, yeast, lactic acid bacteria

- 1-YEAR FERMENTATION - Prebiotics and Probiotics -

A century-old traditional drink, Koso has good bacteria which are Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus casei, Lactococcus lactis. And galactooligosaccharide and dietary fiber are included as prebiotics. Dandelion Greens, Asparagus, apples, Burdock, Barley, Seaweeds act as prebiotics ingredients.


What does R's KOSO taste like?
R's KOSO is a Japanese plum flavored drink.

Is R's KOSO taste vegan?
Yes. R's KOSO taste does not contain animal-derived ingredients and the drink is plant-based.

How long has it been fermented?
R’s KOSO is fermented for about 1 year.

What’s the best way to take R's KOSO?
You can mix 2 tablespoons of R's KOSO with ½ cup of filtered or sparkling water. It's also good to take with yogurt, alcohol.

Is there an optimal time of day to take R's KOSO?
No, it can be taken at any time of the day that suits you. Especially we recommend you drink after you eat/drink too much. It is helpful to digest. Actually many Japanese women take it after dinner or replace the meal.

How does it compare to the Kombucha and other drinks?
R's KOSO is the only 100% plant-based supplement which has probiotics, prebiotics, acetic acid, Phenolics, vegetable, and fruits nutrients, Vitamins (A, B1, B2, B6, C, D, E, and K), Mineral (calcium, phosphorus, potassium, sodium, chloride, magnesium, iodine, iron, zinc, copper, manganese, iodine), 17+ Amino Acids, Short-chain fatty acid.

How different between Juice cleanse and Koso Cleanse?
R’s Koso’s Main feature is the benefit of Gut health. Compared to Juice cleanse, Koso Cleanse has probiotics and prebiotics that have positive impacts on your gut. Some research reveals that the gut is connected to the brain and skin.

Is R's KOSO safe to use when pregnant and when breastfeeding?
Yes, it's all natural plant-based food so you can take it.

Can I take it with other supplements?
Yes, R's KOSO can be taken with every other supplement because it's food.

Does it contain preservatives?
No, it is not contained it. The fermentation process made its shelf life longer.

R's KOSO - Made from 100+ Vegetables, Fruits, rich in Pre+Pro+Postbiotics

*The taste like Sweet Japanese plum juice. We recommend mix with sparkling water. It's going to be Plum Flavor Postbiotic Soda.


✔   Enhanced gut health

✔   Better digestion

✔   Healthy Weight

✔   Help with skin trouble

✔   Boost immunity

✔   Body and Mind Detox

✔   Mental clarity

✔   Better sleep

✔   Improve concentration

1bottle is good for:

✔   Breakfast Cleanse (every day) - 2 weeks

✔   Breakfast Cleanse (4 Days/w) - 4 weeks

✔   1-Day Cleanse - 3-4 weeks

✔   3-Day Cleanse - 1 program

✔   Daily Enjoyment - 2-4 weeks

* One bottle has 16 servings.
Serving size:2 tablespoons (30ml / 1oz) of KOSO mix with 1/2 cup water or sparkling water. 1 serving is calculated for Cleansing. It can be used 1/2 serving for daily enjoyment.  

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R's KOSO - Japanese Postbiotic Drink (474ml / 16oz)×2 bottles

R's KOSO - Japanese Prebiotic Drink (474ml / 16oz) - R's KOSO

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*For the first time, try KOSO. 5 servings are included.
It's not a shot. We recommend mixing with water or sparkling water.

R's KOSO - Japanese Prebiotic Drink (474ml / 16oz) - R's KOSO

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R's KOSO - Japanese Prebiotic Drink (474ml / 16oz) - R's KOSO

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* If you are interested in wholesale plan. Contact us: info@rskoso.com


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