The pancake batter mixed with blueberry jam is purple.

When cooked, the inside turns light green. When a stack is cut open and lemon syrup is poured, the cut surface turns ... pink this time.

Kids love this week’s dish, which changes color. Sally Hiramatsu, who introduces scientific knowledge through familiar cooking, reveals the secret.

“The key is anthocyanin, a pigment contained in the blueberry. It is also present in purple cabbages and grapes,” says the 28-year-old cooking expert who is bent on science.

When neutral, anthocyanin is purple but it turns green or blue when alkaline. When it is acidified, the color turns reddish.

When baking soda, a leavening agent in pancakes, is heated, it turns into a substance that is strongly alkaline. The anthocyanin responds and turns the pancake light green.

Then the citric acid in lemon turns the part covered with the syrup acid, turning it pink. By leaving out the egg from the recipe, the changes in color become more distinct.

When she entered university, Hiramatsu was thinking of becoming a scholar.

“I had no idea that I would be working like this,” she says.

What propelled Hiramatsu into her current path is the “Shuppan Koshien,” a publication contest that turns good projects into books, which she entered in her senior year. Her idea of a cookbook enhanced by scientific knowledge won the grand prize. A number of publishers approached her with offers for publication.

Around this time, Hiramatsu began to feel that she wanted many people to understand the scientific mechanisms around them rather than pursuing a single theme of research. Although she had decided to go on to graduate school, she came up with the idea of becoming a science-based cooking expert after graduation.

“When you focus on science, you discover ‘different faces’ of familiar cooking ingredients. This is fascinating. I think you will become a better cook faster if you understand the mechanisms,” says Hiramatsu.

INGREDIENTS

(Serves three to four)

1 bag prepared pancake mix (150 to 200 grams)

Instructed amount of milk

1.5 to 2 Tbsp blueberry jam

2 Tbsp lemon juice

4 Tbsp sugar

METHOD

Place lemon juice and sugar in heat-resistant container. Make sure sugar is immersed completely in lemon juice. Microwave at 500W for about 1 minute. Cool.

Prepare batter as instructed without egg. Add blueberry jam and mix. (1.5 Tbsp if pancake mix is 150 grams, 2 Tbsp if mix is 200 grams.)

Cook as instructed. The inner part would have changed from purple to light green. The color will then turn to pink when lemon syrup is poured.

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From The Asahi Shimbun's Watashi no Ryori column