Japanese sweet potatoes are a simple food that has truly changed my life…for the better. These purplish-skinned white-flesh sweet potatoes have become a delicacy in my kitchen as well as a simple staple.These unique tubers are so tasty and so simple they are purely a joy to work with.
The Japanese sweet potato is unlike any other from it skin color to creamy flesh and flavor. They are roughly oblong in shape with a thin, purplish colored skin. They have a unique and densely textured cream-colored flesh and when cooked the flesh becomes slightly yellow and they become rich in sweet flavor.
Japanese yams can be grown year-round with their peak season in fall and winter. They are now a common mainstay at Asian markets Farmer’s markets across the U.S. and are grown in many different regions including California.
History
The Japanese sweet potato, is also commonly known as Satsuma-Imo, “mountain yam”, or Kotobuki. Sweet potatoes are botanically classified as Ipomoea batatas, from the Morning Glory plant family.
A sweet potato is the tuber part of the plant, most often storing nutrients and energy in the form of carbohydrates and water, which sustains the plant’s growth and ability to survive adverse conditions making a versatile plant that can be grown in many parts of the world.
Sweet potatoes are considered to be the 7th most important crop in the world but have dropped in consumption in the United States by more then 75% in past 4 decades.(2) Sweet potato are generally thought to be from Central and South America but may also have some origins in Asian. Sweet potato have made their way around the world in cultivation and are grown in many different climates. I have seen them at the local farmer’s markets from New York to California and are a mainstay at almost all Asian markets. Sweet potatoes are not the same as Yams, they have a different geographic and botanical origin.
Medicinal Properties
Sweet Potatoes are one of those mysterious miracle foods. It may not seem like much to the eye but hidden in the skin and flesh of a sweet potato is a multitude of health benefits.
Sweet potatoes have become increasingly recognized as “a powerfully nutritious food that is helpful in the prevention of chronic disease, with endorsements coming from the American Cancer Society, the American Heart Association, and the Center for Science in the Public Interest, among others. In fact, the Center for Science in the Public Interest has even ranked the sweet potato as the most nutritious of all vegetables, mainly for its content of dietary fiber, naturally occurring sugars, protein content, vitamins A and C, potassium, iron, and calcium, as well as its low amounts of fat (especially saturated fat), sodium, and cholesterol. Interestingly, what the typical American diet lacks in nutrients (particularly potassium, magnesium, vitamin C, and carotenoids) and fiber seems to be what the sweet potato contains in abundance.” (2)
The nutritional value of a sweet potato is principally a carbohydrate and is a source of healthy dietary fiber, though if eaten in large quantities it can provide substantial amount of
- Protein
- Vitamin A
- Vitamin C
- Vitamin E
- Calcium
- Potassium
- Magnesium
Japanese sweet potatoes contain approximately 27 grams of carbohydrates
Carbohydrate value comes from three sources: dietary fiber, sugars and starch.
Japanese sweet potatoes contain approximately:
4 grams of dietary fiber, providing about 16 percent of the daily value for fiber.
5 grams of sugars which are predominantly sucrose and glucose, with a small amount of fructose.
17 grams of starch
As an excellent source of dietary fiber Japanese sweet potatoes (and all sweet potoates) make a good candidate for a diabetic diet as it helps to stabilize the blood sugar (3). Because sweet potatoes are high in carbohydrates but low in calories they aid in weight loss promotion. Japanese sweet ptotatoes are one of the foods promoted in the Okinawa diet, one of the “healthiest” diets in the world.Sweet potatoes also have been utilized as functional foods (traditional medicines) throughout Japan for many years.(2)
Other health benefits from sweet potatoes may include(5):
- Stabilizes Blood Sugar
- High in Antioxidants
- Boosts Brain Function
- Enhances Immunity
- Promotes Vision Health
- Aids in Weight Loss
Sweet potatoes may also supportlactation in breast-feeding women because of the high source of beta-carotene and vitamins available.
Sweet potatoes and yams tend to be cooling in thermal nature and sweet in flavor and are grounding by they nature of being a tuber or root crop (meaning they grow in the Earth.)
In Chinese Medicine, they strengthen the spleen-pancreas axis, promotes qi energy, and removes toxins from the body, builds the yin fluid capabilities of the kidneys which benifits dry and inflamed conditions of the body.(4)
Preparation
Preparing Japanese sweet potatoes is easy. My favorite way to cook them is to bake them as shown step by step in the recipe below. You can also bake them whole, steam them for optimal nutrition or add them to soups and stews.
They are practicle for bulk cooking and you may find easy with cook several at a time and having them for the week. If roasting them whole, I tend to cook them low and slow and turn them often. You can bake them at 375 degrees and poke a few fork holes in them. If you have a hotel pan with a cover that is even better. I do not tend to wrap them in tin-foil to keep waste at a minimum.
You can find Japanese sweet potatoes at almost any market these days including Whole Foods. Choose ones that firm and have a nice reddish-purple colored skin.
- Wash the sweet potatoes well in cold water.
- Preheat the oven to 400 degrees F.
- Peeling the skins is optional but the skin is where a lot of the actually vitamins are. When baking I tend to leave the skin on for nutrition and flavor but if you are sensitive to bitter flavors you may choose to not use the skins. When making soups or stews I peel the skins.
- Cut the yams into 1/4 inch thick rounds
- Coat the rounds with coconut oil and salt. You can do this in a large mixing bowl. You can heat the coconut oil slightly so that you may coat the potatoes with liquid oil. Note that oil may if the yams are cold. Place the rounds onto a sheet tray.
- Bake for 30-35 minutes. Check the yams at least half way through and turn the yams to the other side.
Baked Japanese Sweet Potatoes
Cook time
Total time
Author: Medicinal Diet
Ingredients
- 3 medium Japanese potatoes
- 3 T of coconut oil
- sea salt
Instructions
- Pick out your Japanese potatoes at the market. Choose ones that firm and have a nice reddish colored skin.
- Wash the yams well.
- Preheat the oven to 400 degrees F.
- The skins are edible and have good nutritional value. You may choose to take the skins off depending on your preference for flavor and texture.
- Cut the sweet potatoes into ¼ inch rounds
- Coat the sweet potatoes with coconut oil and salt. You can do this in a large mixing bowl. You can heat the coconut oil slightly so that you may coat the potatoes with liquid oil. Note the oil may solidify if the yams are cold.
- Place the rounds onto a sheet, you can use parchment paper for easy.
- Bake for 30-35 minutes. Check the sweet potatoes half through their baking time and turn the rounds over onto their other side.
3.5.3251
References
1. https://www.specialtyproduce.com/produce/Satsumaimo_Potatoes_11707.php
2. Willcox, D. Craig, Hidemi Todoriki and Makot o Suzuki. The Okinawan Diet: Health Implications of a Low-Calorie, Nutrient-Dense, Antioxidant-Rich Dietary Pattern Low in Glycemic Load. The Journal of American College of Nutrition. Volume 28. Published Online June 14,2014.
3. Link, Rachel. Sweet Potato Nutrition Facts and Benefits. https://draxe.com/sweet-potato-nutrition-facts-benefits/ Dec. 17, 2017.
4.Pitchford, Paul. Healing with Whole Foods: Asian Traditions and Modern Nutrition. 3rd Edition. 1993. North Atlantic Books. Berkely, CA.
Leave a Reply