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The most common types of miso are red, white, barley and soybean. Red miso is a mixture of white rice, barley or soybeans fermented for one to three years. It contains the highest levels of protein. White or yellow miso contains a higher percentage of rice koji and less soybeans, is sweeter than red miso and contains a higher percentage of carbohydrates and a lower percentage of protein.

So, to answer your question White or Yellow Miso is sweeter than Red Miso.

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The color can be darker or lighter, and the taste can be sweeter or saltier. The most common kinds of miso are shiro (white) miso and aka (red) miso. The white varieties aren't really white, but are light yellow and have a sweet taste. The red varieties are dark brown and are salty. Shinsyu miso, which is light brown, is also commonly used. Mixed miso called awase miso is popularly sold in supermakets.

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Sweet misos are usually white.

Here's the recipe for Miso paste

1 1/2 cups white miso

3/4 cup sugar

3/4 cup sake

3/4 cup mirin

Combine miso and sugar in the top of a double boiler. Add sake and mirin, and whisk to combine, using a heavy whisk. Cook over boiling water, stirring frequently until sugar is dissolved and the color begins to darken, 30 to 45 minutes. Remove from heat, and cool. Makes about 2 1/2 cups

Miso Soup

Ingredients

1 tablespoon finely grated fresh ginger

1 tablespoon miso paste

2 garlic cloves, smashed

1 teaspoon Chinese chile-garlic sauce

1 teaspoon light brown sugar

1 teaspoon Asian sesame oil

1 1/2 teaspoons fresh lime juice

Directions

Combine all of the ingredients in a bowl and mash to a paste.

Notes

Best Uses Rub the paste on skirt steak, shrimp, spareribs, chicken and pork before grilling, or stir into broth or noodle soup.