Sugar corn or sweet corn (Zea mays saccharata rugosa) is a variety of corn that has a higher sugar content than regular field corn. Sweet corn appears as a consequence of a natural mutation of field corn that affects the activity of a gene responsible for converting sugar into starch, thus resulting in a sweeter variety. Botanically speaking, it is a member of the Zea mays species and is believed to have originated in Southern and Central America. Unlike regular corn which is eaten as a grain, sweet corn is regarded as a vegetable from a culinary point of view.
You might be interested to find out that sweet corn is harvested before it reaches maturity, more exactly in the milk stage. This is done in order for the kernels to remain tender and have a sweet, milky taste. When the kernels mature and become dry, which is also when the sugar turns into starch, sweet corn is no longer as palatable. The variety stands out as a great source of B vitamins such as folic acid, vitamins B1, B3 and B5, vitamin C, iron, magnesium, manganese, copper and potassium.
What does sweet corn look like? The plant can reach rather impressive heights of up to 10 meters and an average height of around 2 meters. It is highly dependent on good weather conditions in order to grow beautifully and produce quality corn cobs with good-tasting kernels. Sunny days and good soil moisture are the prerequisites for delicious sweet corn. Each plant produces around 6 cobs that must be harvested while the kernels are still soft or milky. The corn cob is essential the fruit of the corn plant. It contains seeds called kernels disposed in even rows and is covered by tightly wrapped, elongated, pointy leaves that make up a husk. The leaves are light green when the corn is in the milk stage and light brown and dry when the corn is dry. Each corn cob has a tuft of silk. Sweet corn kernels can be yellow, white or have two colors, depending on the variety.
What does sweet corn taste like? Sweet corn is a culinary vegetable and has a soft, tender, crisp texture and pleasantly sweet taste as a result of a relatively high sugar content. It has not particular flavor. It is estimated that most cultivars have around 5-10% sugar content. If left to dry, sweet corn will lose a lot of its sweet flavor and become even starchier in taste than field corn as the sugar is turned into starch.
Nutrition facts and benefits
Sweet corn is considered to be healthy and figure-friendly, despite having a high sugar content. The delicious sweet kernels have a moderate energetic value: 100 g of raw kernels supply only 86 kcal. Boiled and drained sweet corn has around 96 kcal/100 g while canned varieties (drained solids) may have as little as 67 kcal/100 g. When compared to other cereals such as wheat or rice, sweet corn is definitely the right choice if you want to keep slim, but only if eaten in moderate amounts as part of an overall clean, varied and balanced diet.
As indicated by its sweet taste, it contains simple carbohydrates such as glucose and sucrose. Raw sweet corn kernels provide 18.7 g of carbohydrates per 100 g, of which 6.26 g are sugars. Boiled and drained kernels have 20.1 g of carbohydrates per 100 g, of which 4.54 g are sugars. The current recommended daily intake of carbohydrates for an average adult on a 2000 kcal diet is 275 g of carbs a day. With the amount it contains, sweet corn contributes to elevated energy levels and helps combat hypoglycemia. However, it is not the best choice of food for diabetes because of its high sugar content so it’s best to be eaten in limited amounts.
Like field corn, sweet corn too is a source of protein, providing 3.27 g of protein for every 100 g of raw kernels. However, the protein it provides does not contain sufficient amounts of all essential amino acids so it’s called a source of incomplete protein, compared to meat, fish, eggs and milk which are sources of complete protein. More exactly, studies show corn in general contains too little of the essential amino acids lysine and tryptophan. Lysine is vital for calcium absorption, muscle repair following injury from exercise and the immune system, contributing to antibody production. Tryptophan helps synthesize neurotransmitters in the brain regulating mood, appetite, sleep and cognitive performance.
If you are a vegetarian or vegan, you can eat legumes such as peas, beans or chickpeas together with sweet corn to get all the essential amino acids you need for keeping healthy. The variety is a good source of ferulic acid, a phenolic phytochemical with strong anti-cancer properties. It also contains carotenes beta-carotene, lutein, zeaxanthin and cryptoxanthin. Except for lutein and zeaxanthin, the other carotenes are all precursors of vitamin A. The vegetable is also rich in flavonoids, naturally-occurring compounds with antioxidant and anti-proliferative properties. Studies show the flavonoids in sweet corn may help prevent lung and mouth tumors.
One of the best properties of sweet corn is it’s gluten-free which means that it can be safely consumed by people suffering from celiac disease, gluten sensitivity or wheat allergy. Other gluten-free grains include rice, quinoa, buckwheat and amaranth (see cereals page).
100 g of raw and cooked kernels provides 2 g of dietary fiber, indigestible plant material that passes unchanged through the gastrointestinal tract. Dietary fiber stimulates transit time and helps relieve constipation, also providing benefits for hemorrhoids sufferers. Moreover, studies show it helps decrease LDL (bad) cholesterol levels by reducing the absorption of fats from food.
As seen from the nutritional table of sweet corn above, the culinary vegetable is a moderate source of vitamin C. However, cooking sweet corn causes it to lose all of its vitamin C content because the nutrient is highly sensitive to heat. The same thing is true for all foods rich in vitamin C: they will lose most if not all of it when cooked.
The culinary vegetable is an important source of B vitamins:
– Vitamin B5: 0.717 mg, or around 14.3% of recommended daily intake, RDI
– Vitamin B1: 0.155 mg, around 12% of RDI
– Vitamin B3: 1.770 mg, around 11% of RDI
– Folic acid (vitamin B9): 42 mcg, or 10.5% of RDI
– Vitamin B6: 0.093 mg, around 7% of RDI
– Vitamin B2: 0.055 mg, around 4% of RDI
B-group vitamins promote normal metabolism, restore appetite, help synthesize carbohydrates, fats and proteins, are involved in energy metabolism, contributing to elevated energy levels and are good for muscle, brain and nervous system health. Vitamin B6 is especially important for cardiovascular and skin health. Folic acid is good for pregnant women, helping with normal brain development in babies, and supporting the circulatory system during pregnancy. Vitamin B5 helps synthesize coenzyme A, involved in the synthesis of fatty acids and consequently brain, nervous system and skin health.
Sweet corn further contains small amounts of essential minerals: calcium (2 mg), copper (0.054 mg), iron (0.52 mg), magnesium (37 mg), manganese (0.163 mg), potassium (270 mg), selenium (0.6 mcg), sodium (15 mg) and zinc (0.46 mg). As seen from its nutritional value, sweet corn is an especially good source of potassium and magnesium, two nutrients with benefits for the cardiovascular system and known to promote good blood pressure and muscle health.
Overall, sweet corn is a delicious and healthy food with a good nutritional profile. The vegetable stands out as having an impressive content of B vitamins and a varied mineral profile. It is a source of antioxidants such as carotenoids that give it its characteristic yellow color. All the important complexes in sweet corn work synergically to maintain good vision, strong muscles, beautiful skin and brain, nervous and immune system health. As a culinary vegetable, it can be baked, boiled or roasted or frozen to be eaten another time. Other sweet corn recipes to try include sweet corn on the cob, cornbread, sweet corn and tuna salad or egg, sweet corn and peas risotto.