Why is cooking with steam healthy?

There have been hundreds of diet fads over the years, but healthy eating can be simplified for the majority of people. Consume more produce, cook at home, and try to make healthy foods flavorful. So why doesn't most of the US population reach the recommended daily fruit and vegetable intake? Even though studies show that a variety of produce is key to cardiovascular disease and cancer prevention, systematic challenges and daily life challenges often make healthy habits overwhelming. On the bright side, cooking with the Anova's Precision® Oven and steam is one way to enhance food's nutritional content.

Steam Cooking And Produce

You’ve always been told to eat colorfully because there’s solid evidence that fruits and vegetables can help to prevent many chronic diseases. But it’s not simply apples and kale keeping you healthy; it’s the phytochemical inside. For your body to access these beneficial compounds, studies have found that cooking with steam may actually boost nutritional value. An American Journal of Clinical Nutrition study shared that women who followed a standard nutrition diet vs. raw food diet actually absorbed more beta-carotene, even though those on the raw food diet generally ate more foods with beta-carotene. Another study found that most cooking methods (boiling, baking, etc.) can break down tissues and destroy antioxidants in produce. While each variety is different, the study found that, on average, boiling knocked vegetables' polyphenol levels down by nearly 40%. The good news? Steaming increased the polyphenol average content by over 50%. Steaming's gentle heat can help your body digest and absorb better than some raw versions. Veggies should stay tender and keep texture (i.e. they shouldn’t fall apart, except produce like tomatoes). The Anova Precision® Oven makes overcooking nearly impossible by pairing sous vide mode with steam and a perforated pan so veggies don’t drown. It’s also worth noting that some veggies are more bioavailable when paired with a fat, so drizzling olive oil is a great starting point.

5 Vegetables to Cook with Steam

1. Tomatoes: Cooked tomatoes have significantly higher levels of lycopene vs raw tomatoes.
2. Asparagus: Cooking asparagus boosts antioxidant activity by 16-25%, while also increasing phenolic acid (associated with a reduced risk of cancer). Use the Asparagus 101 guide and add your own seasoning spin.
3. Celery: Cooking celery boosts antioxidant capacity. Try this Thanksgiving Sheet Pan recipe using the Anova Precision® Oven.
4. Carrots: Cooking carrots boosts beta-carotene levels, which is important for the immune system. When carrots are cooked with less water (like in steaming), it significantly increases the bioavailability of beta-carotene. Try these glazed carrots to get started!
5. Green Beans: Besides boosting antioxidant levels when cooked, steaming green beans may be especially helpful in reducing cholesterol. Make these simple green beans tonight.

Steam Cooking with Meat and Poultry

Beyond the importance of cooking meat and poultry to reduce food-borne illnesses, preparing these foods helps denature the proteins to make them more digestible. How often have you had a terribly dry chicken breast or tough, overcooked steak, then coated it with sauce to make it taste better? Since temperature control and steam injection improves tenderness (a marker that highly impacts consumer acceptability with meats), precise cooking also opens the door to higher acceptability of ‘healthier,’ lower saturated fat cuts. In fact, Harvard Medical School recommends steaming as a cooking method for a healthy diet.

Preparing meat at extremely high temperatures can increase disease risk due to the formation of compounds, but so can cooking for long periods using methods that cause nutrient loss. Cooking with steam plus a quick roast or sear to finish can help minimize nutrient loss and the amount of those harmful compounds. Studies show that moist heat at low temperatures like in the Anova Precision® Oven with Sous Vide Mode and steam reduces the formation of compounds known as HCA’s and PAH’s. These are the harmful compounds that can contribute to disease, most often formed in problematic quantities when compounds in meat are exposed to the high temperatures through grilling. As traditional sous vide cooking allows for precision, the ability to deliver a tender, even piece of mean creates a more delicious and nutritious end product with better nutrient retention. A longer cooking time at a lower temperature reduces damage to heat sensitive beneficial compounds, while also reducing cooking loss but increasing collagen solubility.

Steaming For Healthy Eating

Studies show that steam cooking increases the bioavailability of chronic disease-preventing nutrients in produce and reduces the formation of harmful compounds in meat while providing tender, juicy end results. Until now, steaming has been a bit of an unpredictable method with little control. The Anova's Precision® Oven enables exact temperature and steam percentage control for perfectly cooked recipes that retain nutrients and make delicious meals. 

People will eat what tastes good, and controlled steam injection makes flavorful dishes easier. Get started with steam by visiting Anova’s recipe library!

Carlene Thomas, RDN Dietitian Nutritionist, Food & Beverage Photography/Videography @OhCarlene