Cranberry and Relatives

Cranberries can be harvested dry, with a comb-like machine, or wet, by flooding the bog. Dry-harvested berries keep better, for several months. Cranberries store well for a couple of reasons. One is their high acidity, exceeded only by lemons and limes, and the main obstacle to eating them straight. The other is their very high content of phenolic compounds (up to 200 milligrams per 100 grams), some of which are antimicrobial and probably protect the fruit in its damp habitat. Many of these phenolic materials are also useful to us, some as antioxidants and others as antimicrobials. One example is benzoic acid, now a common preservative in prepared foods. A particular pigment precursor in cranberries (also found in blueberries) prevents bacteria from adhering to various tissues in the human body, and so helps prevent urinary tract infections.