Low temperatures kill the smell of bananas

In a recent study, scientists report that low temperatures inhibit the activity of proteins that play a key role in creating the characteristic banana aroma. This finding could improve the fruit's aroma and flavor.

Bananas are one of the most popular fruits in the world. How they are stored before they reach store shelves can negatively impact their aroma and taste.

Tons of bananas eaten

Billions of bananas are eaten worldwide each year. According to the U.S. Department of Agriculture, the typical American consumes about 11 pounds of bananas annually. Most bananas are grown abroad, so to reach the United States intact, they must be transported in freezers. This causes the fruit to ripen later and its flavor to diminish.

Genes and fruit ripening

Previous research has shown that proteins called transcription factors (TFs) help regulate the activity of certain genes involved in fruit ripening. Building on this work, Jian-fei Kuang and his team wanted to find out whether a specific set of proteins suppresses the odor of refrigerated bananas.

Cold and the smell of bananas

To achieve this, the researchers stored freshly harvested green bananas either refrigerated or at room temperature. Once removed from the refrigerator, the bananas ripened more slowly than those stored at room temperature and also developed an unpleasant aftertaste. In a series of experiments, the team found that refrigeration reduced the activity of genes that produce flavor during ripening.

Better banana flavor

By conducting deeper analyses, the researchers identified a pair of transcription factors—MabZIP4 and MabZIP5—that play an important role in activating these genes. A better understanding of this regulatory process could lead to the development of strategies to improve banana aroma.