Why do carrots taste sweeter in the winter?

From the University of California’s Fig.1 series, Molecular Biologist Liz Roth-Johnson explains why cold weather makes carrots taste more sweet:

Because plants are immobile, they must develop defense techniques against predators and the severe cold in winter. For example, carrots have developed the physiological response of increasing their sugar content when it’s cold outside. This helps stop ice crystal formations and prevents damage to the carrot’s cells.

Frost can do a lot of damage to a plant cell. It can squeeze and rupture the cells until they are completely demolished. But in some cases, the plant’s defense mechanism means a tastier vegetable for us to eat. When a carrot defends itself from frost, we get the benefit of enjoying sweeter carrots all winter long.

Related videos include Minute Earth’s How do trees survive winter? and The Story of Frozen Food, as well as Fig 1’s How Mountain Biking Was Invented.