Sprouts and Food Safety
Sprouts cause periodic outbreaks of food-borne illness. In the most recent outbreak, which occurred in Germany, at least 50 people died and thousands were sickened, apparently after eating sprouts grown from imported organic fenugreek seeds that were contaminated with a particularly dangerous strain of E. coli. Many of us like crunchy sprouts in a salad or sandwich. They have an aura of healthfulness and freshness.
- So, are sprouts safe?
- Why are sprouts so big a health risk that food-safety experts have even coined a term for widespread illness caused by themsproutbreaks?
- And why aren't organic sprouts safer?
Raw Food Risks
Any raw or undercooked food carries some risk. That is especially true in under-developed countries, where lack of good sanitation and food-safety systems makes it essential to peel fruit and avoid other uncooked food. But outbreaks are increasingly common in developed countries, especially when produce is contaminated by bacteria from farm animalsusually from manure that is used as fertilizer or gets into irrigation water.
All kinds of sproutsespecially alfalfa, clover and mung beanscan harbor Salmonella, E. coli and other bacteria. Seeds can become contaminated during harvesting, storage or sprouting. Sprouting requires warm, wet conditions that are perfect for bacterial growth. Even if seeds are only slightly contaminated, millions of bacteria can grow during the sprouting process. In any case, it doesn't take many organisms of the virulent strains of E. coli to cause illness. Organic growing methods do not reduce the risk, nor does growing sprouts at home.
Cooking kills these bacteria, but sprouts are usually eaten raw. (Salad greens are risky for the same reason.) Washing sprouts may reduce the risk, but doesn't eliminate it.
That's why the U.S. Food and Drug Administration (FDA) has long warned about sprouts and has worked with growers in attempts to eliminate unsanitary conditions in harvesting and sprouting. The FDA recommends that growers (and home sprouters) sanitize seeds, usually by bathing them in a diluted chlorine bleach solution, but does not require it. And the beans can still become contaminated when sprouting.
Food for Thought about Sprout Safety
If you're in good health, you may wish to continue eating sprouts. Many of us eat risky foods occasionally, such as raw oysters. Life is not risk-free, and foods are not sterile. If you put raw sprouts on a rare hamburger, the hamburger is more likely to make you sick than the sprouts, since undercooked ground meat is a leading cause of E. coli-related illness in the U.S.
Buy sprouts that look crisp and fresh; avoid those that have a musty odor or appear dark or slimy. Purchase sprouts only if they are refrigerated, and keep them refrigerated at 40°F (4.4°C) or below.
The only way to ensure safety is to cook sprouts to 165°F (74°C), but that destroys their most appealing qualities. If you add large bean sprouts to a stir-fry, let them simmer for a few minutes.
Bottom line: People with weakened immune systems, as well as the very old, the very young and pregnant women, should not take a chance on raw sprouts. But when a serious outbreak occurs, as in Germany, anyone can become ill. We think sprouts should carry a warning label saying this.
Source: Originally published in The University of California, Berkeley Wellness Letter (September 2011)