What Is Konjac? Shirataki Noodles, Taste, Nutrition & How to Cook Them

Konjac is a traditional Japanese ingredient made from the konjac plant, while shirataki is one of the best-known noodle forms made from it. In Japan, konjac is eaten in many different shapes, from firm konnyaku blocks to thin shirataki noodles and decorative knots.

Shirataki noodles are known for their mild, neutral flavour and distinctive smooth, springy texture. According to the Japanese Food Composition Database, standard shirataki contains approximately 7 kcal per 100g and is made up largely of water, which is one reason its nutritional profile attracts so much attention.

This guide explains what konjac is, how shirataki differs from konnyaku, what it tastes like, what glucomannan is, the calories and nutrition in shirataki noodles, and how to prepare and cook them.

Official sources: This guide uses information from Japan's Ministry of Agriculture, Forestry and Fisheries (MAFF), the Ministry of Education, Culture, Sports, Science and Technology (MEXT), UK Government guidance and UK legislation. Nutritional values and ingredients can vary between individual products.

■ What Is Konjac?

Konjac is a traditional food made from the konjac plant, Amorphophallus konjac.

The underground part of the plant, commonly referred to as the konjac corm, can be processed into konjac flour. Water and a setting agent such as calcium hydroxide are then used to produce the firm, springy food known in Japanese as konnyaku.

Japan's Ministry of Education, Culture, Sports, Science and Technology describes refined konjac flour as a product made from the konjac plant and used as a raw material for edible konjac products.

In Japan, konjac is available in a number of forms, including:

• Konnyaku blocks
• Shirataki noodles
• Ito konnyaku, or thread konjac
• Konjac balls
• Knotted konjac

These different forms are used in home cooking, regional dishes and traditional Japanese cuisine.

Source: Japan's Ministry of Agriculture, Forestry and Fisheries introduces konjac as one of Japan's traditional processed foods and describes its connection with Japanese regional food culture. View MAFF's konjac information

■ What Are Shirataki Noodles?

Shirataki noodles are thin Japanese noodles made from konjac.

According to Japan's Ministry of Education, Culture, Sports, Science and Technology, shirataki is also known as ito konnyaku. It is traditionally made by forming prepared konjac into fine strands.

In the UK, you may see similar products sold under several names:

• Shirataki noodles
• Konjac noodles
• Konnyaku noodles

Unlike noodles made from wheat, shirataki has a smooth surface and a distinctive springy, slightly chewy texture.

The noodles have a mild, neutral flavour, making them particularly well suited to flavourful broths, sauces and seasonings.

Source: The Japanese Food Composition Database classifies shirataki within the konjac category and gives its English food name as "Konjac/noodles". View the Japanese Food Composition Database

■ Konjac vs Shirataki: What Is the Difference?

Konjac and shirataki are closely related, but the two terms do not mean exactly the same thing.

Konjac is the broader ingredient, while shirataki is one particular form of food made from konjac.

In the UK, konjac noodles and shirataki noodles are therefore often used as similar product descriptions.

However, in Japanese cuisine, konjac includes far more than noodles. Blocks, knots and other shapes are also widely used.

■ Are Konnyaku, Konjac and Shirataki the Same Thing?

These three terms can be confusing if you are new to Japanese food.

Konjac is the English term commonly used for the plant and foods derived from it.

Konnyaku is the Japanese term commonly used for the prepared food made from konjac. It can include blocks and a variety of other shapes.

Shirataki refers specifically to thin strands made from konjac.

Rather than treating all three words as names for completely different ingredients, it is more useful to think of them as closely connected parts of the same Japanese food tradition.

■ What Does Konjac Taste Like?

Konjac has a mild, neutral flavour. Its texture is usually much more noticeable than its taste.

Konnyaku blocks have a firm, bouncy bite, while shirataki noodles are smoother, thinner and slightly slippery, with a springy texture.

This makes shirataki quite different from familiar wheat noodles such as ramen or udon.

Because konjac has a mild, neutral flavour, it works particularly well with flavourful seasonings such as:

• Dashi
• Soy sauce
• Mirin
• Miso
• Sesame-based sauces
• Japanese hot-pot broths

The flavour of the broth, sauce or seasoning therefore plays an important role in the finished dish.

■ What Is Glucomannan?

Glucomannan is a type of polysaccharide naturally associated with the konjac plant.

UK-referenced food specifications describe glucomannan as the principal constituent of konjac flour. It is made primarily from the sugar units mannose and glucose.

Japanese government information also identifies glucomannan as a component of refined konjac flour.

Sources: UK food specifications describe glucomannan as the principal constituent of konjac flour. Japanese government information also identifies glucomannan as a component of refined konjac flour. View UK legislation

■ Konjac Noodles Nutrition: How Many Calories Are in Shirataki?

Standard shirataki contains approximately 7 kcal per 100g according to the Japanese Food Composition Database.

The same database shows that shirataki is made up largely of water.

Nutritional values can differ between products because recipes and manufacturing methods vary. Always check the nutrition declaration on the individual packet.

Source: Nutritional figures for standard shirataki are taken from the Standard Tables of Food Composition in Japan. View the Japanese Food Composition Database

■ Are Konjac Noodles Good for Dieting?

Konjac and shirataki are often searched alongside terms such as "diet" and "weight loss".

According to the Japanese Food Composition Database, standard shirataki provides 7 kcal per 100g, so its nutritional profile differs considerably from many conventional noodle products.

However, it would not be accurate to say that simply eating konjac noodles causes weight loss.

In Great Britain, nutrition and health claims made about foods are regulated. Only authorised claims may be used, and products must meet the specific conditions attached to those claims.

There is an authorised health claim relating to glucomannan and weight loss in the context of an energy-restricted diet, but its use is subject to specific conditions, including requirements relating to the amount of glucomannan consumed.

Source: UK Government guidance explains that nutrition and health claims used for foods in Great Britain must be authorised and used according to specified conditions. View UK Government guidance

■ Are Konjac Noodles Gluten-Free and Vegan?

The ingredients in konjac noodles vary between manufacturers, so always check the individual product.

If you follow a gluten-free, vegan or other specific diet, check the ingredients and allergen information on the packaging rather than assuming that every product labelled "konjac noodles" is identical.

For example, Yutaka Organic Konjac Noodles are currently labelled Gluten Free, Vegan and Organic, while Yutaka Shirataki Noodles are currently labelled Gluten Free and Vegan.

Always refer to the current product page and product packaging for the latest dietary, ingredient and allergen information.

■ How to Prepare and Cook Shirataki Noodles

Shirataki noodles are simple to prepare, but rinsing and briefly heating them before adding sauce or broth can improve their texture.

1. Drain and Rinse

Open the packet, drain away the liquid and rinse the shirataki thoroughly under fresh water.

2. Boil or Dry-Fry

Depending on the product, the noodles can be briefly boiled or heated in a dry frying pan to remove excess moisture.

Yutaka Organic Konjac Noodles can be boiled for approximately two to three minutes or heated in a frying pan after rinsing.

3. Add Your Seasoning

Once excess moisture has been removed, combine the noodles with your chosen broth, sauce or seasoning.

Because shirataki has a mild, neutral flavour, it works particularly well with:

• Soy sauce-based sauces
• Japanese hot-pot broths
• Miso-based sauces
• Sesame dressings
• Stir-fries

■ How Is Konjac Eaten in Japan?

Konjac has long been used in Japanese home cooking, regional cuisine and traditional dishes.

Sukiyaki

One of the best-known uses for shirataki is sukiyaki.

Japan's Ministry of Agriculture, Forestry and Fisheries lists shirataki alongside ingredients such as beef, spring onions, leafy vegetables and tofu in its introduction to Japanese sukiyaki.

Source: MAFF includes shirataki among the typical ingredients used in sukiyaki. View MAFF's sukiyaki guide

Oden

Konjac is also a classic ingredient in oden, where ingredients such as daikon, eggs, fish cakes and konnyaku are gently simmered in seasoned dashi.

Both konnyaku and shirataki appear among traditional oden ingredients in information published by MAFF.

Source: Japan's Ministry of Agriculture, Forestry and Fisheries introduces konnyaku and shirataki as ingredients used in Japanese oden. View MAFF's oden guide

Hot Pots and Simmered Dishes

Shirataki and other types of konnyaku are also used in Japanese hot pots and simmered dishes such as nikujaga.

Their mild flavour and springy texture make them well suited to dishes where they can be cooked in a seasoned broth alongside vegetables, tofu, meat or seafood.

■ What Can You Make with Shirataki Noodles?

Shirataki noodles can be used in traditional Japanese dishes as well as more contemporary noodle meals.

If you are trying shirataki for the first time, sukiyaki, Japanese hot pot or a well-seasoned stir-fry are easy places to start.

■ Where to Buy Konjac and Shirataki Noodles in the UK

Konjac and shirataki are available in the UK through Japanese food shops, Asian supermarkets and specialist online retailers.

At Yutaka Shop Online, you can choose between different types of konjac and shirataki noodles depending on the dish you would like to make.

■ Konjac and Shirataki: The Key Things to Remember

The easiest way to understand konjac is to remember that it is much more than a type of noodle.

Konjac has been part of Japanese food culture for generations and can appear as blocks, noodles, knots and other forms.

Shirataki is simply one of the best-known noodle forms made from konjac.

For cooking, remember:

drain → rinse → briefly boil or dry-fry where appropriate → add flavour

For nutrition, use the actual information for the product you are eating. Standard shirataki is listed at approximately 7 kcal per 100g in the Japanese Food Composition Database, but individual products can vary.

And while konjac is frequently associated online with dieting and weight loss, food-related health claims in Great Britain are regulated. It is therefore better to focus on the product's actual nutritional composition rather than assuming that eating konjac automatically produces a particular health outcome.

■ Frequently Asked Questions

■ Sources

• Ministry of Agriculture, Forestry and Fisheries (MAFF), Japan — Konnyaku

  Japanese government information about konjac as a traditional processed food and its place in Japanese food culture.

  View MAFF konjac information
• Standard Tables of Food Composition in Japan — Shirataki

  Official Japanese food composition data covering the classification and nutritional composition of shirataki, including energy, water and dietary fibre.

  View Japanese food composition data
• Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan

  Government reference information covering konjac flour, konjac foods and the preparation of shirataki.

  View MEXT information
• UK Legislation — Konjac and Glucomannan

  Food specification information describing konjac flour and glucomannan.

  View UK legislation
• UK Government — Nutrition and Health Claims Guidance

  Guidance explaining the framework for nutrition and health claims made about foods in Great Britain.

  View UK Government guidance
• UK Legislation — Authorised Health Claims

  Legislative information covering authorised health claims and the conditions attached to claims relating to glucomannan.

  View authorised health claims
• Ministry of Agriculture, Forestry and Fisheries (MAFF), Japan — Sukiyaki

  Official Japanese regional cuisine information showing shirataki among the ingredients traditionally used in sukiyaki.

  View MAFF sukiyaki information
• Ministry of Agriculture, Forestry and Fisheries (MAFF), Japan — Oden

  Official information on oden and the traditional use of konnyaku and shirataki.

  View MAFF oden information
• Yutaka Shop Online — Organic Konjac Noodles

  Product-specific information including ingredients, nutritional values, dietary preferences and preparation guidance.

  View Yutaka Organic Konjac Noodles
• Yutaka Shop Online — Shirataki Noodles

  Product-specific information including ingredients, nutritional values, dietary preferences and suggested uses.

  View Yutaka Shirataki Noodles