[Editor's note: For information on the recent recall of soybean sprouts sold in Virginia, Maryland, and Washington, D.C., click here. For the recent recall of alfalfa sprouts, click here: http://www.fda.gov/Safety/Recalls/ucm303305.htm]

Raw seed sprouts (such as alfalfa and radish sprouts) have long been touted as a health food.  And there are good reasons for this: they’re an excellent source of many essential nutrients including protein, as well as being a popular, tasty addition to salads and sandwiches. However, unfortunately, sprouts are also a very common source of pathogens (especially salmonella and E.coli) and illness.  FoodSafety.gov (a website from the U.S. Dept. of Health and Human Services) says that, since 1996, there have been at least 30 reported outbreaks of food borne illness associated with different types of raw and lightly cooked sprouts.  (Two or more cases of the same food-associated illness is considered an outbreak.)

Food preservation--in other words, extending shelf life--has been a widely-practiced human endeavor since the days of cave people.  (Forget that sexist term "cave men.")  According to the website PartSelect, cave folk who lived in cold locations froze fish, seal meat, and other small animals by storing them on ice.  In warmer climates, drying was the ancient method of choice for food preservation. Later, to freezing, drying, and fermenting, the Romans added pickling and canning. 

In modern times, science has provided additional ways to extend shelf life, especially techniques, currently widespread, that can keep foods fresh longer in the refrigerator. Now, scientists are working on ways to extend the shelf life of foods that are customarily refrigerated, making them safe and tasty at room temperature for longer periods of time. Read on to discover the "supersandwich" with a shelf life, at room temperature, of 3-5 years!  But let's start with the somewhat high-tech processes that most consumers come in contact with regularly, though they may not realize it.