“Just when we need these vegetables most, in the bleakest part of the winter, they give us the sustenance to carry on until spring. Their texture and sweetness come from a combination of starches and sugars. To the plant, starches represent food that has been stored for future use, while sugars can be immediately converted to energy. Starches are chemical compounds that resemble tough little pellets when raw. After they are heated in combination with a liquid, they soften.

Sugars are closely related to starches. In fact, enzymes produced by the plant can convert starches (stored food) to sugars (usable food) when doing so is necessary for the plant’s survival. This is why parsnips are almost always sweeter when harvested after a hard frost: the plant, feeling threatened by cold weather, has started converting its stored food to food that can be used immediately.

Properly selected and prepared, all root vegetables turn sweet. What makes root vegetables so fascinating is the diversity of secondary attributes they possess. In general these fall into two main categories, the sharp and the colorful. The first typifies the flavors of vegetables such as radishes, kohlrabi, rutabagas, turnips and horseradish and comes from a combination of a mustardy sulfurous compound that in nature functions as a defense mechanism. Other roots, while lacking in inner fire, are among the most vibrantly colored members of the vegetable kingdom.

Root vegetables adapt well to both moist- and dry-heat cooking methods. Moist heat, such as that from boiling or steaming, softens the vegetables’ starch and cellulose more quickly and keeps colors brighter and flavors purer and more direct. Dry-heat cooking (primarily roasting) takes longer. The colors tend to be darker and not quite so fresh, and the flavors developed are more complex.”

Excerpted from the excellent book by Russ Parsons How to Pick a Peach: The Search for Flavor from Farm to Table

Recipe for Turnip Appetizer