The onion-nutritional characteristics


The onion-nutritional characteristics

Onion is a very healthy complement at the same time be very useful in the kitchen.

The Onion is an essential in any pantry ingredient, but perhaps to be so accessible at times may seem even insignificant. And nothing is further from reality, as the onion is a very healthy at the same time be very useful in the kitchen. And it is, to its antioxidant, anti-inflammatory and antimicrobial effect – thanks to its great contribution of high quality fiber, flavonoids and sulphur-compounds, should add the possibilities offered to brighten up our salads, enhance FRY or the taste of other foods in many dishes.

In time of gourmet food for foodies, the onion wins integers by its simplicity, versatility and ease of access for all budgets. In short, these are the reasons that will look at it with different eyes:

  • Great contribution of water. As is the case with most of the vegetables, onion has a large proportion of water (up to 90%), which helps to hydrate our diet.
  • Few calories. “Your caloric intake is very low, as he is specifically estimated that he adds some 40 Kcal per 100 grams of edible part when it is consumed raw,”, explains Angeles Carbajal, Professor of nutrition of the Faculty of pharmacy of the University Complutense of Madrid, who adds that “it has small amounts of carbohydrates simple (between 3% and 9%) and some protein (1%) so it contains no fat or cholesterol.”
  • Fiber quality. Among the main features of the onion is the quantity and quality of dietary fiber that provides, a 2% approximately, since it is a type of soluble fiber, mainly fructooligosaccharides, which is very appropriate to maintain good intestinal health.
  • Contribution of minerals. This vegetable is not exempt of vitamins or minerals. In particular, in its interior is present potassium, phosphorus, magnesium, iron and even calcium, while sodium is very low.
  • Vitamins. Stand in the onion the vitamins of Group B, such as folic acid, as well as vitamin C, present in approximately 19 mg. “in any way, such as consumption, although widely used, is relatively low, since it is usually about 20 – 30 g per person and day (an onion of a 140 – 200 grams per week), the contribution of minerals and vitamins” except that of potassium or vitamin C if it is eaten raw, is not very relevant in the diet”, said Professor Carbajal.

The onion-nutritional characteristics

The compounds in onions might help prevent various diseases.

The onion, as is the case with other foods from plants of the genus Allium (garlic, spring onion, shallot or Leek), has a large number of bioactive compounds that appear to have an important role in health: “Onion is attributed properties diuretic, antibiotic, expectorant, antithrombotic and cleansing, among other benefits, which make it useful as antihypertensive, hiporcolesterolemico” “flattering of digestive functions, and even some types of cancer-preventive role has been described in scientific works”, says María Teresa Nestares, Coordinator of the Master’s degree in human nutrition from the University of Granada.

The health benefits of onion reside in the presence of:

  • Functional fiber: the onion contains fructooligosaccharides, a type of soluble fiber not digestible by intestinal enzymes, making it selectively stimulate the activity of beneficial bacterial species that already reside in the colon (probiotics).

“To not be digestible, reach the lower portion of the intestine where they are fermented by Bifidobacteria, which manages to reduce the pH of the medium and inhibits the emergence of other pathogenic bacteria.” In fact, today in day include those Fructo-oligosaccharides in foodstuffs as Prebiotics”, explains Nestares.

  • Flavonoids: primarily quercetin and canferol, which are natural antioxidants from plants. Quercetin is the most abundant dietary flavonoid and onions are one of the main sources of this phytochemical.

Its value lies in that “contributes to inhibition of the oxidation of low density lipoproteins (LDL-cholesterol), by helping to prevent the risk of cardiovascular disease, not to mention that also the flavonoids present in onion have been associated with the reduction of blood pressure and platelet antiaggregatory activity, i.e., which prevents thrombus formation” confirms María Teresa Iglesias, Professor of Pharmacology, nutrition and dietetics of the Universidad Francisco de Vitoria of Madrid.

  • Sulfur compounds: are those who contribute the characteristic flavour to the onion, but also their strong smell. These volatile substances are those which come from the onion to cut it and the guilty produce itching and tearing, as well as an effect of expectorant when it reaches the respiratory tract. These components are that synthesizes the plant for its own defense and the purple varieties of onion has bigger.

“The anti-inflammatory and anti-asthmatic ability of onions is due in part to the presence of thiosulfinates (sulfur compounds). In addition, the raw onion exerts a powerful antifungal and antibacterial effect”, adds Iglesias.

All these compounds present in the onions “have an important antioxidant, anti-inflammatory and antimicrobial function so it is currently studying possible preventive role in cardiovascular diseases, hypertension, hypercholesterolemia, diabetes, some types of cancer (mainly esophagus and stomach) and diseases of the respiratory system, among others.” Either way, will be necessary more studies to have scientific evidence”, says Angels Carbajal, Professor of nutrition at the Universidad Complutense, who adds that”by the presence of these components, the onion may also be considered a functional food, but should not be forgotten that the role of diet in health and disease prevention is the consequence of all the foods we eat and not one single”. Although the onion, as we see, is full of goodness and is a perfect ally for your health.

The onion-nutritional characteristics

In moderate amounts, and in the context of a balanced diet, the onion has no contraindications.

The Spanish society of community nutrition (SENC) recommended to include in the diet at least two servings a day of vegetables, although most advisable is to increase the intake to 400 grams per day. And there it enters in the foreground onion, as the SENC advises to “employ daily herbs, spices, garlic and onions because of the numerous nutritional benefits and the beneficial effects that have health, without forgetting that its use often result in a lower use of salt”.

Therefore, either raw or cooked, anyone must include the onion in your daily diet. “It is interesting to note that cooking, such as frying or cooking processes, do not cause large losses on the total content of flavonoids in onion, the dishes with her are a good source of these components,” says the Professor of Pharmacology, nutrition, and dietetics Maria Teresa Iglesias.

However, yes there are some properties that are disadvantaged when it comes to cooking the onions. In this line, Teresa Nestares explains that “culinary treatments which undergo vegetables cause losses of nutrients, primarily in two ways: loss of water-soluble compounds in the cooking water (some vitamins, minerals…)” and loss for inactivation or destruction (primarily vitamins). From the nutritional point of view is therefore recommended its crude consumption and, if cooking, take care of the preparation and cooking to minimize losses.”

When you should avoid eating onions

Consumed in moderate amounts, and in the context of a balanced diet, the onion has no contraindications. However, by its high sulfur content can be irritating and cause stomach burning, so it is not a food recommended in excess for people with gastrointestinal problems, reflux or with renal pathology.

“Flatulence and gastroesophageal reflux problems that suffer from some individuals can avoid consuming it cooked rather than raw or using the onion or scallion or milder onion varieties.” Some people may reject this food by smell and taste or problems with flatulence or gastrointestinal upset, but we can not generalize, because these effects depend on many individual factors,”said Angeles Carbajal, Professor of nutrition of the Complutense University of Madrid.

The onion-nutritional characteristics

The Onion is a fundamental ingredient in the typical dishes of the Mediterranean diet.

The Onion is one of the essential ingredients of the Mediterranean diet, so that their use in the kitchen is very common and is widespread. Its main advantage is that you get to season any dish and has many possibilities for consumption, since it can be included in a large number of dishes. These are some of the uses of the onion in its different versions:

  • Raw onion: is perfect for including in salads or cold snacks.
  • Fried onion: can be a good companion complete salads, as well as meat, burgers and fish.
  • Cooked onion: is very common in stews, sauces and stir-fry; either meat, fish or seafood.
  • Pickled onion: is ideal for an aperitif.

Types and varieties of onions (put a picture of each type of onion)

In addition, another advantage of the onions in the kitchen is the diversity of flavors offered, thanks to the variety of species that can be found easily at the grocery store at any time of the year:

  • Sweet Onion: is the most common and also the most versatile in the kitchen. Its color is yellow to brownish. Sweeter makes its great presence of sugar, and due to its characteristics it is suitable for frying and broiling.
  • Onion: is the milder taste, although it has a spicy leave, and is more suitable for eating raw, since it also provides a nice colour to your salads, sandwiches, ceviche, or pasta.
  • White onion: aspect seems larger and their skin is thinner. As for flavor, it has a more intense taste and its texture is more crispy, so it is perfect for frying and for inclusion in sauteed.
  • Chives: its appearance is long, thin and its flavor is softer and sweeter than common common yellow onion. It is very suitable to eat raw, since it is juicy and crispy, and chopped stem can enhance the flavor of other dishes.
  • Shallot: this type of Onion is a classic in French cuisine. Its more delicate and mild flavor makes it very demand for cooking in dishes that don’t want to subtract prominence to the main ingredients, such as shellfish, or egg-based recipes.

The onion-nutritional characteristics

Check that onions are soft and have enough outer layers, which are those that protect them.

When we are in the supermarket, should look onions to choose those that best suit our needs, but also those that are best preserved. For this reason, it is recommended to choose them one by one, and not in bags that are already closed.

“It is advisable to look at are not soft and they have a good natural wrapper, i.e., carrying sufficient outer layers that are those that protect them. Content in antioxidants and natural preservatives substances of the onion is precisely the greatest in these outer layers, because its mission is to protect the plant, to the onion, the deterioration”, explains Angeles Carbajal, Professor of nutrition at the Complutense University of Madrid.

In these conditions the onion are preserved well several days without refrigeration, provided that they are in a dry and cool place, but when it comes to fresh onions, preferably keep them early on in the fridge. In any case, once cut, it is necessary to keep them in the refrigerator well covered with transparent paper. In this way may also be several days in the refrigerator, although with the passage of time, they tend to dry out.

Another good alternative is to opt for the already frozen onion there are supermarkets, since it helps to keep the vitamins. In fact, “most commercial frozen foods are processed as close to the source of supply that its content of vitamins like Ascorbic acid (vitamin C) is often greater than the fresh food that you spend time in the store, traveling and on the shelves of supermarkets,” clarifies the Professor María Teresa Nestares an expert in human nutrition at the University of Granada.