Japanese Food Guides
Japanese Food Guides
Why Japanese Chefs Use Koji: The Secret Behind Natural Umami
by B2C Yamasan
on Jul 31 2026
For centuries, Japanese chefs have relied on one powerful ingredient to create deep flavor, natural sweetness, and incredible umami: koji.
Although many people outside Japan are only beginning to discover it, koji has long been an essential part of traditional Japanese cuisine and fermentation culture.
Today, professional chefs around the world are also embracing koji for its ability to transform ingredients and elevate cooking naturally.
So why do Japanese chefs use koji so often?
What Is Koji?
Koji (麹) is made by fermenting steamed rice, barley, or soybeans with a beneficial mold called Aspergillus oryzae.
During fermentation, koji produces natural enzymes that break down proteins and starches into amino acids and sugars.
This process creates:
Rich umami flavor
Natural sweetness
Greater depth and complexity
Improved texture
Koji is the foundation of many traditional Japanese foods, including:
In Japan, koji is often called The heart of Japanese fermentation.
Miso View Collections
Soy sauce View Collections
Sake
Mirin
Amazake
Shio Koji View Products
Without koji, Japanese cuisine as we know it would not exist.
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Koji product
1. Koji Creates Natural Umami
One of the main reasons Japanese chefs use koji is that it naturally increases umami.
The enzymes in koji release amino acids such as glutamate, which are responsible for savory flavor.
Instead of relying on artificial flavor enhancers, chefs can use koji to create a deep, satisfying taste naturally.
This is why many Japanese dishes feel rich and flavorful even when they use simple ingredients.
2. Koji Makes Meat and Fish More Tender
Koji is also widely used as a marinade.
When meat or fish is marinated with shio koji or koji-based seasonings, the enzymes help break down proteins gently.
As a result:
Meat becomes more tender
Fish develops a richer flavor
Clean-label products
Ingredients stay juicy during cooking
Many chefs compare koji marination to natural aging techniques because it improves texture and depth without overpowering the original ingredient.
Today, "koji marinade" has become increasingly popular among chefs worldwide.
3. Koji Enhances Ingredients Naturally
Japanese cuisine often focuses on bringing out the natural qualities of ingredients rather than covering them with strong seasoning.
Koji helps chefs achieve this balance beautifully.
Instead of adding heavy sauces, koji enhances:
Sweetness
Aroma
Umami
Complexity
This creates elegant and balanced flavors that are central to Japanese cooking philosophy.
4. Koji Supports Fermentation Culture
Fermentation has always played an important role in Japanese food culture.
Japanese chefs use koji not only for flavor but also as part of traditional food preservation and fermentation techniques developed over centuries.
Koji allows chefs to create:
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Sake
Mirin
Amazake
Shio Koji View Products
These fermented foods contribute depth, character, and tradition to Japanese cuisine.
5. Modern Chefs Are Rediscovering Koji
Today, chefs around the world are experimenting with koji in new and creative ways.
Koji is now used in:
Steak marinades Kankoji SteakView Recipe
Vegan cooking Koji NattoView Product
Plant-based cheese
Sauces and dressings: Fermented Tomato SauceView Recipe
Desserts Lemon Koji SyrupView Recipe
Fine dining fermentation
Many modern chefs appreciate koji because it offers:
Clean-label flavor enhancement
Natural fermentation
Reduced need for additives
Sustainable cooking possibilities
As interest in fermented foods and gut-friendly eating grows globally, koji continues to gain attention far beyond Japan.
A Traditional Ingredient for Modern Cooking
Koji has been quietly shaping Japanese cuisine for over 1,000 years.
What makes it special is not only its history but also its ability to naturally improve flavor, texture, and depth in cooking.
From traditional Japanese kitchens to modern restaurants worldwide, chefs continue to use koji because it transforms simple ingredients into something extraordinary.
At Yamasan, we are proud to share authentic Japanese fermentation culture from Kyoto, Japan, with customers around the world.
Discover the rich world of koji and experience the natural power of Japanese fermentation in your own kitchen.
Japanese Food Guides
What Is Japanese Sake? A Complete Beginner's Guide to Japanese Rice Wine
by B2C Yamasan
on Jul 30 2026
Japanese sake is a traditional alcoholic beverage made by fermenting rice, koji (rice malt), water, and yeast. Often referred to as Japanese rice wine, sake is brewed using a unique fermentation process that creates a wide range of flavors, from light and fruity to rich and full-bodied.
Whether you're just beginning your sake journey or looking to expand your knowledge, understanding the different Japanese sake types, serving temperatures, and food pairings will help you enjoy sake even more.
1. Main Types of Japanese Sake
◆Junmai (Pure Rice Sake)
Junmai is made using only rice, water, koji, and yeast, without added distilled alcohol.
Flavor Profile
Rich rice flavor
Full-bodied umami
Smooth and well-balanced
Best With
Grilled dishes
Simmered Japanese foods
Meat dishes
Cheese
◆Ginjo & Daiginjo
Ginjo and Daiginjo are brewed with highly polished rice, producing elegant and aromatic sake.
Flavor Profile
Fruity and floral aromas
Light, delicate body
Clean finish
Best With
Sushi
Sashimi
Carpaccio
Fresh appetizers
Fruit
◆Honjozo
A small amount of brewer's alcohol is added to create a lighter, cleaner taste.
Flavor Profile
Crisp
Refreshing
Easy to drink
Best With
Tofu
Sushi
Soba noodles
Salads
Everyday Japanese meals
2. How to Drink Japanese Sake
One of the unique characteristics of Japanese sake is that it can be enjoyed at different temperatures, each offering a different tasting experience.
Chilled (Yuki-bie / Hana-bie) – Highlights fruity aromas and freshness, ideal for Ginjo and Daiginjo.
Room Temperature – Brings out balance and complexity.
Warm (Nurukan / Atsukan) – Enhances sweetness and umami, especially for Junmai and Honjozo.
Experimenting with serving temperatures is one of the best ways to discover your favorite style.
3. How to Choose Japanese Sake
If you're wondering how to choose sake, pay attention to these points:
Sweet or dry (Sake Meter Value / SMV)
Rice Polishing Ratio (Seimai Buai)
Sake classification (Junmai, Ginjo, Daiginjo, Honjozo)
Fresh (Nama Sake) or Pasteurized
These label details provide useful clues about the sake's aroma, body, and flavor.
4. Japanese Sake Pairing Guide
Pairing food with sake can enhance both the drink and the meal. In Japan, sake is often grouped into four flavor styles.
◆Aromatic Sake (Kunshu)
Elegant, fruity, and floral.
Examples
Ginjo
Daiginjo
Pairs Well With
Appetizers
White fish sashimi
Carpaccio
Fresh fruit
◆Refreshing Sake (Soushu)
Light, clean, and refreshing.
Examples
Honjozo
Nama Sake
Low-alcohol sake
Pairs Well With
Cold tofu
Boiled vegetables
Sushi
Soba
Caesar salad
◆Rich & Umami Sake (Junshu)
Full-bodied with deep rice flavors.
Examples
Junmai
Yamahai
Kimoto
Pairs Well With
Simmered dishes
Yakitori
Sukiyaki
Steak
Gyoza
Cheese
◆Aged Sake (Jukushu)
Complex aromas of dried fruit, nuts, and spices.
Examples
Koshu (Aged Sake)
Pairs Well With
Grilled eel
Braised pork
Mapo tofu
Dark chocolate
5. Three Simple Rules for Sake Pairing
Match the Color
Light-colored sake pairs beautifully with delicate dishes, while darker, aged sake complements richer, darker foods.
Match the Occasion
Premium Daiginjo is perfect for special meals such as fresh sashimi, while everyday sake pairs wonderfully with home-cooked dishes.
Match the Temperature
Serve chilled sake with cold dishes like salads and sushi, and enjoy warm sake alongside hot pots, grilled foods, and comforting winter meals.
YAMASAN Sake Ware
Guinomi Sake Cup Set of 5
Mount Fuji Sake Cup Pair
Premium Japanese Sakeware Set
Japanese Food Guides
Koji vs Miso vs Soy Sauce: What’s the Difference?
by B2C Yamasan
on Jul 30 2026
Japanese cuisine is famous for its rich umami flavor and deep fermentation culture.
Among the most important traditional Japanese ingredients are koji, miso, and soy sauce. Although they are closely connected, many people are confused about how they differ.
So what exactly is the difference between koji, miso, and soy sauce?
In this guide, we'll explain each one simply and explore how they are related in Japanese cooking.
What Is Koji?
Koji (麹) is the foundation of many Japanese fermented foods.
It is made by fermenting steamed rice, barley, or soybeans with a beneficial mold called Aspergillus oryzae.
During fermentation, koji produces natural enzymes that break down starches and proteins into sugars and amino acids.
This creates:
Natural sweetness
Rich umami
Deep flavor
Fermentation activity
Koji itself is not usually eaten alone in large amounts. Instead, it is used to make many traditional Japanese seasonings and fermented foods.
In Japan, koji is often called The heart of Japanese fermentation.
Add Koji Paste to Cart
Add Semi-Dried Shio Rice Koji to Cart
Koji product
What Is Miso?
Miso (味噌) is a fermented soybean paste made using koji, soybeans, and salt.
In other words, Koji is one of the key ingredients used to make miso.
Depending on the ingredients and fermentation period, miso can taste:
Natural sweetness
Rich umami
Deep flavor
Fermentation activity
Miso is commonly used in:
Natural sweetness
Rich umami
Deep flavor
Fermentation activity
Because miso is fermented for months or even years, it develops a complex umami flavor loved around the world.
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Miso product
What Is Soy Sauce?
Soy sauce is another traditional Japanese seasoning made through fermentation with koji.
Traditional soy sauce is typically made from:
Soybeans
Wheat
Salt
Koji
During fermentation and aging, koji enzymes help create the deep savory flavor and aroma that soy sauce is known for.
Soy sauce is widely used for:
Seasoning
Dipping
Cooking
Marinades
Its flavor is salty, rich, and highly umami.
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Soy sauce collection
The Relationship Between Koji, Miso, and Soy Sauce
The easiest way to understand the relationship is this:
Koji is the fermentation starter
Miso is a fermented paste made with koji
Soy sauce is a fermented liquid seasoning made with koji
Without koji, traditional miso and soy sauce could not exist.
Quick Comparison
Koji
Fermentation starter
Mildly sweet
Rich in enzymes
Used to create other fermented foods
Miso
Fermented soybean paste
Thick texture
Rich and savory flavor
Often used in soups and sauces
Soy Sauce
Fermented liquid seasoning
Salty and umami-rich
Used as an all-purpose seasoning
Why Are These Ingredients Becoming Popular Worldwide?
As interest in:
Fermented foods
Gut-friendly eating
Japanese cuisine
Natural umami
Clean-label cooking
continues to grow; more people are discovering the traditional power of Japanese fermentation.
Chefs and home cooks around the world are now using koji, miso, and soy sauce to add depth and complexity to everyday cooking naturally.
Discover the World of Japanese Fermentation
At Yamasan, we are proud to share authentic Japanese fermentation culture from Kyoto, Japan.
Whether you are exploring koji for the first time or already enjoy traditional Japanese seasonings, understanding the connection between koji, miso, and soy sauce is the perfect introduction to the rich world of Japanese fermentation.
Japanese Food Guides
Why Natto Is Considered One of Japan’s Greatest Superfoods
by B2C Yamasan
on Jul 30 2026
In Japan, few traditional foods are as iconic — or as nutritionally impressive — as Natto. Made by fermenting soybeans with Bacillus subtilis (natto bacteria), natto has been enjoyed for centuries as a daily source of nourishment and wellness.
Its sticky texture and rich umami flavor may surprise first-time eaters, but behind that distinctive character is a remarkable combination of plant protein, vitamins, minerals, and unique fermented compounds that support everyday health.
What Makes Natto So Special?
Unlike ordinary soybeans, natto gains additional nutrients and enzymes during the fermentation process. This means you get both the natural goodness of soybeans and the benefits created by fermentation.
A single pack of natto (about 45g) contains:
High-quality plant protein
Dietary fiber
Vitamins B2, B6, E, and K
Calcium, iron, magnesium, and potassium
Natto-specific compounds such as nattokinase and vitamin K2
It’s a small food packed with an impressive nutritional profile.
Rich in High-Quality Plant Protein
Natto contains about 7.4g of protein per pack, comparable to roughly 54g of beef chuck roast.
Protein is one of the body’s essential nutrients. It helps build muscles, skin, hair, organs, hormones, and antibodies. Because natto is made from soybeans, it provides a high-quality plant-based protein source that fits naturally into balanced diets.
For people looking for more plant-forward meals, natto is an easy and satisfying option.
A Great Source of Dietary Fiber
Modern diets often lack enough fiber, but natto naturally contains both:
Soluble fiber — supports fullness and digestive balance
Insoluble fiber — helps maintain healthy digestion and gut movement
One pack contains about 3g of dietary fiber, roughly comparable to several small carrots.
This combination makes natto especially popular among people interested in gut health and everyday wellness.
Vitamin B2: A Key Benefit of Fermentation
One of natto’s standout nutrients is Vitamin B2 (riboflavin).
Soybeans themselves contain relatively little B2, but fermentation dramatically increases it. Vitamin B2 helps the body convert carbohydrates, proteins, and fats into energy and supports healthy skin, hair, and nails.
This is one reason fermented foods are so valued in traditional Japanese food culture.
Vitamins That Support Everyday Wellness
Vitamin B6
Vitamin B6 plays an important role in enzyme function, nervous system health, and red blood cell production. It also supports healthy skin and daily vitality.
Vitamin E
Known for its antioxidant properties, Vitamin E helps protect cells and supports healthy circulation.
Vitamin K
Natto is especially famous for its high Vitamin K content — particularly Vitamin K2, which is produced during fermentation. Vitamin K helps support normal blood clotting and healthy bones by helping the body utilize calcium properly.
Important Minerals in Natto
Natto also provides a variety of essential minerals:
With just:
Calcium— supports bones and teeth
Iron— helps transport oxygen throughout the body
Magnesium— involved in hundreds of enzyme reactions
Potassium— helps balance sodium levels in the body
Even in small servings, natto offers a surprisingly broad range of nutrients.
Unique Compounds Found Only in Natto
Nattokinase
One of natto’s most talked-about compounds is nattokinase, an enzyme created during fermentation. It does not exist in plain soybeans.
Nattokinase is widely known in Japan as a component that supports healthy circulation and overall wellness.
Soy Isoflavones
Soy isoflavones resemble the hormone estrogen in structure and are often associated with beauty and wellness support, especially for women.
Lecithin
Lecithin is a phospholipid connected to brain and nerve function and is often associated with memory and cognitive health.
Polyamines
Polyamines are compounds involved in cellular activity and healthy aging, making natto a food often associated with long-term vitality.
The Power of Soybeans + Fermentation
What makes natto truly fascinating is how fermentation transforms an already nutritious ingredient into something even more beneficial.
Soybeans already contain protein, minerals, and beneficial plant compounds. But when fermented into natto, they gain additional nutrients like Vitamin K2 and nattokinase — nutrients not naturally present in soybeans alone.
This combination of:
Traditional Japanese fermentation
Plant-based nutrition
Convenient everyday eating
is why natto continues to be loved across generations in Japan.
A Simple Traditional Food with Modern Appeal
As more people around the world explore fermented foods and plant-based nutrition, natto is gaining attention far beyond Japan.
Whether enjoyed over rice, mixed into bowls, paired with noodles, or incorporated into modern recipes, natto is one of the easiest ways to add traditional Japanese wellness foods into everyday life.
Sticky, flavorful, and incredibly nutrient-dense — natto truly is one of Japan’s hidden superfoods.
Explore Our Natto Collection
Discover traditional Japanese natto products crafted for everyday wellness, nutrition, and authentic flavor.
Dried Natto
Natto Fermented Soybean Powder
Natto Furikake Seasoning
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Japanese Food Guides
by B2C Yamasan
on Jul 30 2026
Discover the essence of Japanese superfoods with Yamasan Kyoto Uji. Our selection includes nutrient-rich staples like natto, koji, and miso, each offering unique flavors and versatility in the kitchen. Explore our Healthy Choices collection to find these traditional foods and incorporate them into your daily cooking.
🌿 Natto: A Fermented Tradition
Natto, made from fermented soybeans, is renowned for its distinctive texture and long history in Japanese cuisine. It's traditionally enjoyed over rice or mixed into rice bowls, and offers a good source of plant-based protein and fiber. Our Natto Fermented Soybean products offer a convenient way to enjoy this traditional food at home.
Explore Our Natto Series
🍶 Koji: The Fermentation Catalyst
Koji, a fermentation starter made from rice inoculated with Aspergillus oryzae, is fundamental in producing various Japanese condiments, including miso, soy sauce, and shio koji. It's the foundation of umami flavor in traditional Japanese cooking. Incorporate koji-based products into your meals to enhance flavor and depth.
Explore Our Koji Series
🍲 Miso: The Umami-Rich Paste
Miso, a fermented soybean paste, is a staple in Japanese cuisine known for its savory, umami-rich flavor. It has been a cornerstone of Japanese home cooking for centuries. Try our full and varied range of both Miso Pastes and Miso Powders to add depth to your soups, marinades, and sauces.
Explore Our Miso Collection
🛒 Explore Our Healthy Choices
At Yamasan Kyoto Uji, we're committed to offering products that align with a health-conscious lifestyle. Our Healthy Choices collection features vegan-friendly, non-GMO, and additive-free options, allowing you to enjoy authentic Japanese flavors while supporting your well-being.
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Embrace the tradition and rich flavors of Japanese superfoods with Yamasan Kyoto Uji. Visit our online store to discover these and other wholesome products crafted with care and authenticity.
