Are Vitamins Preserved by Stress Cooking?  

How does Dr. Greger stress steam his greens? 

In a assessment of multiple hundred articles concerning the results of cooking on greens, researchers tried to search out the candy spot. On the one hand, warmth can destroy sure vitamins, however then again, softening the tissues could make them extra bioavailable. Researchers settled upon steaming as the very best cooking methodology to protect probably the most vitamin as a result of the vegetable isn’t dunked in water or oil the place the vitamins can leach out and extreme dry-heat temperatures aren’t reached both. They acknowledge, nonetheless, that of the entire frequent cooking strategies, we all know the least about stress cooking, as you may see within the graph beneath and at 0:37 in my video Does Stress Cooking Protect Vitamins?.

There are all types of fancy electrical stress cookers, just like the On the spot Pot. They’re nice for rapidly cooking dried beans with only a contact of a button, however what occurs to the vitamin? Let’s have a look at black beans. (See the chart beneath and at 1:01 in my video.) The antioxidant content material of presoaked black beans boiled for about an hour, a ordinary cooking time, is excessive, nevertheless it’s even increased when stress cooked for 15 minutes. In reality, researchers discovered six instances the antioxidant ranges within the pressure-cooked beans. I’ve been pressure-cooking beans simply because I like their texture higher (the canned ones could be a bit mushy for me) and dried beans are so low-cost in comparison with canned ones. However now we all know they’re tastier, cheaper, and more healthy. That’s fairly the triple menace. 

What about pressure-cooking greens? As you may see beneath and at 1:35 in my video, vitamin C is one of many extra heat-sensitive vitamins. Researchers discovered that sautéing spinach or amaranth leaves in a pan for 30 minutes destroyed about 95 p.c of the vitamin C, whereas ten minutes in a stress cooker worn out solely about 90 p.c. However who stress cooks spinach for ten minutes or sautés it for half an hour? Regardless, even then, not many results have been discovered both manner on beta-carotene ranges. 

Vitamin C is however one in every of many antioxidants, although. What concerning the results of stress cooking on general antioxidant capability? At 2:07 in my video and beneath, you may see a desk of various cooking strategies researchers in contrast—for instance, 12 minutes of boiling, 5 minutes of stress cooking, and 6 minutes of microwaving carrots. The researchers discovered that cooking carrots elevated their antioxidant potential and stress cooking practically doubled their antioxidant worth. In distinction, irrespective of how peas have been cooked, their antioxidant capacities took a success.  

What about greens? Chard wasn’t affected a lot throughout the board, however for spinach, microwaving beat out each stress cooking and boiling, and stress cooking beat out boiling—though stress cooking is definitely boiling, however in much less time and at a better temperature. Nonetheless, the cooking time appeared to trump the temperature; the researchers noticed considerably much less nutrient loss when pressure-cooking spinach for 3 and a half minutes in comparison with boiling for eight. 

The researchers discovered the identical factor with these magical cancer-fighting glucosinolate compounds in cruciferous greens, that are the healthiest ones, together with kale, collards, and turnip greens. As you may see within the graph beneath and at 3:08 in my video, they had the very best nutrient ranges once they have been uncooked. Three-quarters have been worn out by boiling, however lower than half have been eradicated by stress cooking. Steaming beat each strategies, retaining extra vitamins than boiling or stress cooking, as a result of the greens weren’t dunked in water, which might leach out the vitamins. However, though the pressure-cooked greens have been immersed simply as a lot because the boiled greens have been, there have been solely half the nutrient losses, presumably as a result of it was solely half the cooking time—seven minutes stress cooking in comparison with 15 minutes boiling. 

What in the event you reduce down that point much more by stress steaming, as an example, by including a layer of water on the backside of an electrical stress cooker, dropping it in a metallic steaming basket, then placing within the greens and steaming them below stress? That’s how I prepare dinner the greens I eat on daily basis. I’ve at all times liked collards, particularly in Southern-inspired cooking or Ethiopian delicacies, and I discovered I might get that very same melt-in-your-mouth texture just by steaming them below stress for zero minutes. Zero minutes? Sure. Simply set the stress cooker to zero so it shuts off as quickly because it reaches the cooking stress, then instantly open the quick-release valve to launch the steam. The greens end up tender, a brilliant emerald, and cooked to perfection. Give it a strive, and let me know what you assume. 

I like protecting sensible subjects—ones we may have to think about day-to-day when making selections. Take a look at a few of my different movies, together with some cooking ones, within the Associated Movies beneath.