I’m not a fan of thinking about foods only in terms of what they offer nutritionally, or how “healthy” they are for you. Of course there are foods that are better or worse, but food has significance beyond just the vitamin and mineral content. That being said, I do think you might as well get everything out of the foods you are eating. However, with one food in particular this might take a little bit more prep work. Some of you may be familiar with the idea of letting crushed garlic sit for ten minutes before cooking it. Here’s why that actually matters.
The beneficial properties of garlic come from a sulfur-containing compound (which are responsible for the heat of garlic) called allicin. But allicin forms only when garlic is chopped or crushed, because an inactive precursor, alliin, is converted by oxidation to the substance you want. Allicin is a powerful antibiotic, can help lower blood pressure and cholesterol and help prevent chronic diseases such as cardiovascular disease, and cancer. I use scientific names mostly just for fun and so can you the next time you tell someone to eat their garlic.
Heating garlic may destroy or reduce allicin. The health benefits of garlic are numerous, and while garlic is delicious enough to eat no matter what, you might as well get these awesome benefits. A study in the Journal of Nutrition completed in 2001, heated garlic in the microwave for 60 seconds, or in the oven for 45 minutes. They found that after they heated the garlic the nutritional value had gone down. When the researchers crushed the garlic beforehand, and let it sit for 10 minutes prior to heating it, more of the allicin was preserved.
So here’s the deal should you freak out if you are cooking and forget to leave your garlic for 10 minutes? Definitely not. Pat yourself on the back for making a delicious home cooked meal and move on with your bad self. Do scientists know with absolute certainty that letting crushed garlic sit will you turn you into a super human? Also no. But if you do happen to remember, it is a great way to get a little more out of your garlic cloves, and I’m pretty into that. If you’re interested in learning more about cooking times and temperatures for garlic check out this link.
There’s really not enough allicin content in onions to worry about preserving it in this way. Onions, and onion relatives like leeks and chives, are not where you get your allicin from, but they do have other beneficial sulfur-containing compounds that are great for your microbiome (especially raw onions).