The Mighty Sweet Potato

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The Mighty Sweet Potato
Presented by Melissa Hsu Laura Prevo Reiko
Sudduth Kali Tupper
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Introduction

• Sweet potatoes are a tuberous morning glory
• Also known as batatas, el boniato, camote, and
  erroneously, yams
• A species distinct from both yams and potatoes

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Introduction

• Sweet potatoes are cultivated in tropical and
  subtropical regions
• North Carolina is the leading producer in the
  U.S.
• Harvested September December
• Can be found fresh, canned or frozen year-round
  at any grocery store
• Best to choose unblemished, wrinkle-free skin
• Store in a cool, dark place
• Do not refrigerate

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Health Benefits

• Sweet potatoes are a source of dietary
  carotenoids, especially ß-carotene 8
• Our bodies can use ß-carotene to make vitamin A,
  helping prevent a vitamin A deficiency 10
• Consuming carotenoids, including ß-carotene, from
  whole foods regularly may
• Decrease the risk of cancers such as breast,
  esophageal, pancreatic, stomach, and lung cancer
  8, 3
• Promote heart health 8
• Improve blood sugar regulation 9,11
• Enhance the function of the immune system 8

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Health Benefits cont.

• In young adults aged 1830 years old, carotenoids
  may promote lung16 and heart health,6 and lower
  the risk for hypertension5 and inflammation.6
• The CARDIA and YALTA studies
• Serum carotenoids measured
• a-carotene, ß-carotene, lutein/zeaxanthin,
  ß-cryptoxanthin, and lycopene
• Sweet potatoes may have antibacterial and
  antifungal properties, as revealed in lab
  studies.18,12

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Health concerns

• Unlike whole food sources of carotenoids,
  supplemental forms of ß-carotene are associated
  with an increased risk of cancer
• Sweet potatoes contain approximately 2699 mg of
  oxalates per half cup serving 13
• Oxalates occur naturally in plants and can
  crystallize in body fluids if they become
  concentrated in large amounts in the body,
  causing health problems 4
• Individuals with the following health conditions
  are advised to avoid sweet potatoes 13
• Calcium oxalate kidney stones
• High urine oxalate levels (hyperoxaluria)

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Bioactives Carotenoids in Sweet Potato
Carotenoids in 100 g of Sweet Potato Alpha Carotene (µg) Beta Carotene (µg) Lutein Zeaxanthin (µg)
Sweet potato, raw, unprepared 7 8,509 0
Sweet potato, cooked, baked in skin, without salt 43 11,509 0
Sweet potato, cooked, boiled, without skin 0 9,444 0
Sweet potato chips, unsalted 0 14,205 0
Sweet potato, canned, mashed 0 5,219 0
Sweet potato leaves, cooked, steamed, without salt 0 550 2,633
Source http//ndb.nal.usda.gov/ndb/foods/list
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Sweet Potatoes vs. Carrots Side-by-Side
Comparison of Beta-Carotene Content
Beta-Carotene (µg) Beta-Carotene (µg)
Preparation Method Sweet Potato (100 g) Carrot (100 g)
Raw, unprepared 8,509 8,285
Cooked, baked in skin, without salt 11,509  
Cooked, boiled, without skin 9,444 8,332
Chips, unsalted 14,205  
Canned, mashed 5,219  
Cooked, steamed, without salt 550  
Source http//ndb.nal.usda.gov/ndb/foods/list    
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Getting the most from your tatoe

• Carotenoid content can vary with
• Age of root when harvested
• Amount of moisture while growing
• Mineral content of the soil
• Virus infestation
• Burri B. Evaluating sweet potato as an
  intervention
• food to prevent vitamin A deficiency. Compr Rev
• Food Sci Food Saf. 201110118-130.

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Getting the most from your tatoe

• Choose those with the deepest orange-colored
  flesh.
• white lt cream lt yellow purple lt orange
• orange up to 1000 times the beta carotene of
  white

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Getting the most from your tatoe

• Beta-carotene well retained during cooking
• Typical losses 0-12 (boiling, steaming, canning)
• Up to 41 lost (dehydration)
• Cooking process breaks down food matrix and
• makes carotenoids more bioavailable
• Eat with some fat
• Beta-carotene absorbed via micelles
• 3-5 grams of fat increases absorption from lt1 to
  gt25

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Recipe
Mashed Sweet Potatoes and Goat Cheese This
creamy, versatile dish can be served warm or cold
and is sure to be a crowd pleaser. Choose
organic, dark orange sweet potatoes for maximum
flavor and carotenoids. Preparation time 20
minutesMakes 6 1/2-cup servings
Method Peel sweet potatoes and slice into one
inch rings. Steam 10 minutes, or until soft and
fully cooked. Place cooked sweet potatoes along
with remaining ingredients in a stand mixer
fitted with a whip attachment. Mix on low speed
until smooth and creamy.
Ingredients 1 pound sweet potatoes 4 ounces
goat cheese, crumbled 3 tablespoons butter,
softened 1/2 teaspoon salt 1/4 teaspoon
ground white pepper
Adapted by Laura Prevo from PCC Natural Markets
at http//www.pccnaturalmarkets.com/pcc/recipes/pc
c-mashed-yams-and-goat-cheese, author PCC Deli.
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Did you know

• NASA selected sweet potatoes for long-term space
  travel due to their amazing nutritional content
• The Center for Science in the Public Interest
  (CSPI) named sweet potatoes as their 1 Best
  Food

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Did you know

• Orange sweet potatoes may be part of the solution
  to vitamin A deficiency in Africa

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Questions to ponder.

• Sweet potatoes have been proposed as a solution
  to prevent vitamin A deficiency in developing
  countries.
• What do you think are the benefits of providing
  sweet potatoes instead of vitamin A or carotenoid
  supplementation to these populations?
• What ways of preparation are the best for optimal
  carotenoid release from the food matrix?

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References

• Bengtsson A, Namutebi A, Larson Alminger M,
  Svanberg U. Effects of various traditional
  processing methods on the all-trans-beta-carotene
  content of orange sweet potato. J Food Comp
  Anal. 200821134-143.
• Burri B. Evaluating sweet potato as an
  intervention food to prevent vitamin A
  deficiency. Comprehensive Reviews in Food Science
  and Food Safety. 201110118-130.
• Fraser PD, Bramley PM. The biosynthesis and
  nutritional uses of carotenoids. Prog Lipid Res.
  200443(3)228-65.
• Holmes RP, Kennedy M. Estimation of the oxalate
  content of foods and daily oxalate intake. Kidney
  Int. 200057(4)1662-7.
• Hozawa A, Jacobs DR Jr, Steffes MW, Gross MD,
  Steffen LM, Lee DH. Relationships of circulating
  carotenoid concentrations with several markers of
  inflammation, oxidative stress, and endothelial
  dysfunction the Coronary Artery Risk Development
  in Young Adults (CARDIA)/Young Adult Longitudinal
  Trends in Antioxidants (YALTA) study. Clin Chem.
  200753(3)447-55.
• Hozawa A, Jacobs DR Jr, Steffes MW, Gross MD,
  Steffen LM, Lee DH. Circulating carotenoid
  concentrations and incident hypertension the
  Coronary Artery Risk Development in Young Adults
  (CARDIA) study. J Hypertens. 200927(2)237-42.
• Kosambo LM, Carey EE, Misra AK, Wilkes J,
  Hagenlmana V. Influence of age, farming site,
  and boiling on pro-vitamin A content in sweet
  potato (Ipomoea batas (L.) Lam.) storage roots. J
  Food Technol Afr. 19994(3)77-84.
• Krinsky NI, Johnson EJ. Carotenoid actions and
  their relation to health and disease. Mol Aspects
  Med. 200526(6)459-51.
• Kusano S, Abe H. Antidiabetic activity of white
  skinned sweet potato (Ipomoea batatas L.) in
  obese Zucker fatty rats. Biol Pharm Bull.
  200023(1)23-6.
• Low JW, Arimond M, Osman N, Cunguara B, Zano F,
  Tschirley D. A food-based approach introducing
  orange-fleshed sweet potatoes increased vitamin A
  intake and serum retinol concentrations in young
  children in rural Mozambique. J Nutr.
  2007137(5)1320-7.