When people think of onions they tend to think of bad breath and watery eyes. But what they sometimes overlook are onions' many health benefits.
According to UW-Madison professor of nutritional sciences Pete Anderson, eating onions has been shown to lower cholesterol, benefit the health of the heart and reduce the risk of cancer. Onions contain thiosulfinates, chemicals that, among other benefits, appear to decrease the risk of a heart attack by limiting the degree to which blood platelets stick together.
But ironically, the same thiosulfinates that provide health benefits are also the chemicals that cause onions to smell and taste pungent, making them undesirable to some consumers. So for the last 16 years UW professor of horticulture Michael Havey has been trying to develop a onion more consumer-friendly onion that provides the same health benefits but with less tanginess.
\The hotter the onion, the better it is for you. However, you're not going to eat a hot onion without cooking it, but that's driving off some of the health benefits,"" Havey said. ""So we're trying to develop an onion that is sweet to offset the pungency, so you can still have the thiosulfinates, still have the blood thinning effect, but hopefully it will taste sweeter.""
This all leads to what UW horticulture professor Irwin Goldman calls the ""pungency paradox.""
""The more pungent [the onion] is, the more value it has as a medicine, but the less chance anyone can eat it raw,"" Goldman said. ""You have to breed not for increased medicinal strength, but for lower pungency.""
The researchers rely on selective breeding to develop their onions. They pick onions with high sugar content or low pungency and cross-breed them to cultivate onions with even higher sugar levels and even less bitterness.
""We've now identified the biochemical process so that when we say sweet, we mean sweet. It's got more sugar in it and it's got more fructose in it,"" Havey said.
However, though the breeding process sounds simple in theory, translating it into actual practice requires patience.
""The breeding is really a long process because is takes two years to go through one cycle of the [onion] plant's life,"" Goldman said. ""So it probably takes about 20 years from start to finish to develop a new onion variety.""
Although the finished product may be years away, experts say consumers may be able to cook onions in ways that maintain the onions' health benefits such as cooking them in a wok or saut??ing them in certain oils. The department of horticulture is currently researching methods of cooking that may preserve these benefits.