Preparing Your Kale (and Leafy Greens) for Smoothies
I’m a 56 year old man who does not take very good care of himself (but I’m trying…). As part of a weight loss program, I’m using a protein powder from Costco. Lately, I’ve been freezing fruit and making my smoothies with the powder, frozen fruit and orange juice. Tonight I thought to add some veggies to it and put in some frozen spinach. It was pretty good, and I sure more beneficial that fruit, only. I’ve heard that kale was a very good vegetable to use. When I read up on it, I discovered that steamed kale was better that raw kale. How would it be if I steamed the kale and then froze it for later use in my smoothies?
OK, first of all I want to say this is where we enter the category of so much confusing nutritional information out there that people throw their hands up in the air and give up. Ultimately kale is incredibly nutritious raw or steamed. I did do a lot of research on this and the debate seems to be split 50/50. Here is a great blog article. Cancer studies for example show that raw kale is more beneficial than cooked and cholesterol studies show that steamed kale is more beneficial than raw. It just depends on the study and what they set out to prove. T. Colin Campbell’s book, Whole: Rethinking the Science of Nutrition, is a really interesting expose on how nutritional studies get funded and researched. So, don’t give up or throw in the towel, if you are eating kale raw or cooked, 5 gold stars.
I love the idea of steaming it and using it later frozen for your smoothies. This is a fantastic alternative to frozen fruit for keeping your smoothie cold! So let’s get into why you might want to steam your kale and how to prepare them for easy future use in your smoothies.
First of all, I do want to point out contraindications for kale. If you are taking blood thinning medications kale might not be the best idea for you because kale promotes clotting. The greens contain oxalates which in lab tests have been associated with kidney stones and some gallstones so check with your medical doctor before you consume tons of kale.
I will say, as somebody who loves kale chips and has been known to sit down to an entire head of kale in chip form from time to time, kale can be hard on your digestive system – if you eat that much in a whole sitting! It can cause bloating, gas, tummy aches and cramping raw. In that respect, you can get away with eating more kale in one sitting if you lightly steam it. Life lesson, go easy in your smoothies, juices and salads and kale chip servings! 😉
Also kale contains a compound that can suppress thyroid function in certain people. Some say that cruciferous vegetables such as broccoli, cauliflower, collards, brussel sprouts, cabbage, mustard greens, kohlrabi, turnip, and kale, should always be cooked because they can disrupt thyroid hormone production. They do this by blocking thyroid peroxidase and disrupting messages that are sent across membranes of thyroid cells and cooking these vegetables greatly reduces these negative effects. So if you have thyroid issues, then it might be a great idea to look at lightly steaming your leafy greens.
Other reasons for lightly steaming your leafy greens is that it starts the digestive process for you. Lightly steaming breaks down the cellular structure of vegetables and greatly increases the digestibility and nutrient absorption of nutrients in vegetables according to the “you should slightly cook your veggies camp.”
One of the main benefits of lightly steaming your greens is that you will destroy toxins microorganisms. Pathogenic bacteria will be killed when exposed to heat. This is great news!
So let’s look at how we are going to do this. I had some collards and kale I needed to use up in my fridge before my next green bin of organic produce arrived today, so it was perfect timing. Kale crops are often sprayed with pesticides. I believe they might even be on the dirty dozen list, so if you can, be sure to buy organic and wash well!
Start by washing your greens and cutting them down slightly. Place them in a large soup pot with a little bit of water covering the bottom. Steam them just enough to break them down. Take the greens along with some of the water which will contain the antioxidants and nutrients that have boiled off the kale and place it in your high speed blender. Pour the blended mixture into ice cube trays. Freeze. Place in freezer bags for future use in smoothies! 🙂
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I’m basically lazy, so just whir my greens and roll them into a log in a baggy (to prevent freezer burn). Love to put them into smoothies or pestos when winter rolls along. It is easy to cut with a knife or even just break off a piece of the roll. Your ice cube method works best for steamed greens, tho, cause steamed greens get more hard. Love that you kept the water, too. That’s a great idea!
RandyThill Your method sounds great too! Thanks for sharing! I just froze some pesto sauce in ice cube trays tonight too! Isn’t it just the greatest way to extend summer? Thanks for commenting and leaving your method too! 🙂 Namaste, Melissa
I made them but couldn’t take it off the ice tray yet ha, try a gain tomorrow….can’t wait
piyawadee_whan Hope you like them! I certainly find it easier to grab a frozen “green” cube in the morning! Cheers! Melissa
I am just getting on board with green smoothies, & because I need a low oxalate diet, I am forced to cook most of my greens. Love the ice cube idea! Watched your video & you are adorable!! Sending Infinite Love & Gratitude
marciamarcia1 Thanks so much! This idea is going to work really well for you then! 🙂 Cheers! 🙂 Melissa
I had to give up my smoothies because I found out kale (and other cruciferous veggies) inhibit my thyroid function. I decided to use good ol google to ask “can you use steamed kale in smoothies” (because well hot kale in a smoothie sounded disastrous!) This article was the very first link that popped up. I haven’t tried it yet but I just want to thank you in advance! This is an AWESOME idea!! I can’t wait to start having my smoothies again!! Also I’ll be telling my other thyroid disease ridden buddies who gave it up they too can enjoy smoothies again! 😀
Colleen04 That is really cool that you were led to this blog post Colleen! I’m so glad this is going to allow you to have green smoothies again! Yahoo! Thanks for sharing with your thyroid friends. I appreciate that! 🙂 Cheers! Melissa
I am type 2 diabetic and am taking metformin for it. I also take .5 mg of synthroid for a thyroid condition that has been around for years-(not even sure why I take it).
Anyways, is kale in a smoothie an issue for me.
Thank you
re: thyroid condition… Kale is fine (both raw and cooked), however you should avoid soy products and large amounts of raw spinach as both of these are not good for people who are hypothyroid. You seem to be on a relatively low dosage so you should be fine. Just try not to eat spinach every day, but if you prefer spinach to kale, try to blanch your spinach before using it
Thanks Emma 🙂
chipper1 This sounds like a perfect question for your medical doctor at your next medical appointment, they would know better the your specific thyroid conditions, medications and nutrition condtraindications. Thanks, Melissa
This is a great video, thank you! I do this with my pesto all the time, but never though to do it with the greens. My garden is overflowing with kale, beets and bok choy. I’m going to get busy 🙂
JenniferBurke Great time for it! Have fun! 🙂
I have been making my smoothies like this for a while, steaming, blending and poring into ice cube trays, you should not use the liquid, poor it down the sink.
Thanks Gert, good to know. 🙂 Cheers, Melissa
Why is it not good to use the liquid? Assuming you washed the kale throughly before steaming.
Oxalates: Kale, along with many other leafy greens, contains oxalates, which are naturally occurring compounds that can form crystals and may contribute to the formation of kidney stones in susceptible individuals. While steaming kale can help to reduce the oxalate content compared to raw kale, the liquid from steamed kale may still contain some oxalates. If you have a history of kidney stones or are at risk of developing them, you may want to limit your intake of kale juice or kale broth.
Is it okay to steam for 2 minutes in the microwave?
Sure 🙂