I recently picked up Jo Robinson’s bestselling book Eating on the Wild Side. It’s a accessible but jam-packed read discussing the nutrient content of produce. It offers practical and often non-intuitive tips for picking the most bang for your buck, nutrient-wise, in the grocery store.
One of the most interesting tips that stood out to me was how to store lettuce in a way that makes it last longer and can double the antioxidant levels.
How to Store Lettuce, according to Jo:
1. After purchasing, soak your lettuce in cold water for 10 minutes then spin dry in a salad spinner. This slows the aging process and makes the lettuce last longer.
2. Now comes the interesting part: a day or two before serving, tear your lettuce into bite-sized pieces. This can double the antioxidant levels! The lettuce produces more antioxidants as a protective measure against the damage. However, it makes the lettuce wilt more quickly, which is why you should do this only a day or so before serving.
3. Next, create a “microperforated bag” to prolong the life of the lettuce. Put your lettuce – torn or not torn, depending on when you will eat it – in a zip-top bag, press out the air and seal the top. Next, use a pin to make 10-20 evenly spaced holes. Store this on a shelf in the fridge, not in the crisper drawer.
Why? According to Jo, this creates the perfect humidity and allows the optimal exchange of carbon dioxide and oxygen. If the lettuce is stored in a bag without the holes, it produces too much CO2 and wilts. If it’s stored open to the air in the fridge, the excess oxygen causes wilting. The tiny pin pricks allow the optimal exchange of O2 and C02.
If you avoid using plastic bags, you might try these Reusable Produce Bags. They’re designed to maintain the correct humidity in the fridge like the homemade bag option. As of writing this post, I’ve ordered them but I haven’t tried them yet.
Other tips for increasing the nutrient value of your salad from Jo’s section on lettuces in her book:
- Purchase fresh heads of spinach, rather than bags of spinach, and eat it soon after purchasing. Spinach stored for a week has half the antioxidant value of freshly picked ones.
- Larger heads of spinach have more antioxidants than baby spinach leaves.
- Radicchio has four times the antioxidant value of romaine. Toss some shredded radicchio into your salad for a burst of color and nutrients!
- Enjoy your salad with a homemade dressing based with a healthy fat, such as olive oil or pastured egg yolks. The fatty acids are co-factors for the minerals and vitamins in the lettuce, meaning they work synergistically and allow your body to absorb these nutrients. A 2012 Purdue Study discussed in Jo’s book found that olive oil is seven times more powerful than soybean oil in making the lettuce nutrients available. (Regular salad dressings are usually made with inflammatory oils such as canola oil, safflower oil or soybean oil).
Have you ever tried this method of storing lettuce?