The Cabbage Family: Effects of Chopping

Different preparation and cooking methods give different flavor balances in cabbage relatives. It's been found, for example, that simply chopping cabbage -- for making coleslaw, for example -- increases not only the liberation of flavor compounds from precursors, but also increases the production of the precursors. And if the chopped cabbage is then dressed with an acidic sauce, some pungent products increase sixfold. (Soaking the chopped cabbage in cold water will leach out most of the flavor compounds formed by chopping, at the same time that it hydrates the leaves and makes them crisper. When cabbages and their relatives are fermented to make sauerkraut and other pickles, nearly all of the flavor precursors and their products are transformed into less bitter, less pungent substances.

On Food and Cooking by Harold McGee