Fragaria × ananassa, commonly known as strawberry or garden strawberry, is a hybrid species that is cultivated worldwide for its fruit. The fruit (which is not a botanical berry, but an aggregate accessory fruit) is widely appreciated for its characteristic aroma, bright red color, juicy texture, and sweetness. It is consumed in large quantities, either fresh or in prepared foods such as preserves, fruit juice, pies, ice creams, milkshakes, and chocolates. Artificial strawberry aroma is also widely used in many industrialized food products.
The garden strawberry was first bred in Brittany, France, in the 1750s via a cross of Fragaria virginiana from eastern North America and Fragaria chiloensis, which was brought from Chile by Amédée-François Frézier in 1714.
Cultivars of Fragaria × ananassa have replaced, in commercial production, the woodland strawberry (Fragaria vesca), which was the first strawberry species cultivated in the early 17th century.
Technically, the strawberry is an aggregate accessory fruit, meaning that the fleshy part is derived not from the plant's ovaries but from the receptacle that holds the ovaries. Each apparent "seed" (achene) on the outside of the fruit is actually one of the ovaries of the flower, with a seed inside it.
History
The first garden strawberry was grown in France during the late 18th century. Prior to this, wild strawberries and cultivated selections from wild strawberry species were the common source of the fruit.
The strawberry fruit was mentioned in ancient Roman literature in reference to its medicinal use. The French began taking the strawberry from the forest to their gardens for harvest in the 1300s. Charles V, France's king from 1364 to 1380, had 1,200 strawberry plants in his royal garden. In the early 1400s western European monks were using the wild strawberry in their illuminated manuscripts. The strawberry is found in Italian, Flemish, German art, and English miniatures. The entire strawberry plant was used to treat depressive illnesses.
By the 1500s references of cultivation of the strawberry became more common. People began using it for its supposed medicinal properties and botanists began naming the different species. In England the demand for regular strawberry farming had increased by the mid-1500s. Instructions for growing and harvesting strawberries showed up in writing in 1578. By the end of the 1500s three European species had been cited; F. vesca, F. moschata, and F. viridis. The garden strawberry was transplanted from the forests and then the plants would be propagated asexually by cutting off the runners.
Two subspecies of F. vesca were identified; F. sylvestris alba and F. sylvestris semperflorens. The introduction of F. virginiana from Eastern North America to Europe in the 1600s is an important part of history because this species gave rise to the modern strawberry. The new species gradually spread through the continent and did not become completely appreciated until the end of the 18th century. When a French excursion journeyed to Chile in 1712, it introduced the strawberry plant with female flowers that resulted in the common strawberry that we have today.
The Mapuche and Huilliche Indians of Chile cultivated the female strawberry species until 1551 when the Spanish came to conquer the land. In 1765, a European explorer recorded the cultivation of F. chiloensis, the Chilean strawberry. At first introduction to Europe, the plants grew vigorously but produced no fruit. It was discovered in 1766 that the female plants could only be pollinated by plants that produced large fruit; F. moschata, F. virginiana, and F. ananassa. This is when the Europeans became aware that plants had the ability to produce male-only or female-only flowers. As more large-fruit producing plants were cultivated the Chilean strawberry slowly decreased in population in Europe, except for around Brest where the Chilean strawberry thrived. The decline of the Chilean strawberry was caused by F. ananassa.
Cultivation
Strawberry cultivars vary widely in size, color, flavor, shape, degree of fertility, season of ripening, liability to disease and constitution of plant. Some vary in foliage, and some vary materially in the relative development of their sexual organs. In most cases, the flowers appear hermaphroditic in structure, but function as either male or female. For purposes of commercial production, plants are propagated from runners and, in general, distributed as either bare root plants or plugs. Cultivation follows one of two general models—annual plasticulture, or a perennial system of matted rows or mounds. A small amount of strawberries are also produced in greenhouses during the off season.
The bulk of modern commercial production uses the plasticulture system. In this method, raised beds are formed each year, fumigated, and covered with plastic to prevent weed growth and erosion. Plants, usually obtained from northern nurseries, are planted through holes punched in this covering, and irrigation tubing is run underneath.
Runners are removed from the plants as they appear, in order to encourage the plants to put most of their energy into fruit development. At the end of the harvest season, the plastic is removed and the plants are plowed into the ground. Because strawberry plants more than a year or two old begin to decline in productivity and fruit quality, this system of replacing the plants each year allows for improved yields and denser plantings. However, because it requires a longer growing season to allow for establishment of the plants each year, and because of the increased costs in terms of forming and covering the mounds and purchasing plants each year, it is not always practical in all areas.
Runners are removed from the plants as they appear, in order to encourage the plants to put most of their energy into fruit development. At the end of the harvest season, the plastic is removed and the plants are plowed into the ground. Because strawberry plants more than a year or two old begin to decline in productivity and fruit quality, this system of replacing the plants each year allows for improved yields and denser plantings. However, because it requires a longer growing season to allow for establishment of the plants each year, and because of the increased costs in terms of forming and covering the mounds and purchasing plants each year, it is not always practical in all areas.The other major method, which uses the same plants from year to year growing in rows or on mounds, is most common in colder climates. It has lower investment costs, and lower overall maintenance requirements. Yields are typically lower than in plasticulture.
A third method uses a compost sock. Plants grown in compost socks have been shown to produce significantly higher oxygen radical absorbance capacity (ORAC), flavonoids, anthocyanins, fructose, glucose, sucrose, malic acid, and citric acid than fruit produced in the black plastic mulch or matted row systems. Similar results in an earlier 2003 study conducted by the US Dept of Agriculture, at the
Agricultural Research Service, in Beltsville Maryland, confirms how compost plays a role in the bioactive qualities of two strawberry cultivars. Strawberries are often grouped according to their flowering habit. Traditionally, this has consisted of a division between "June-bearing" strawberries, which bear their fruit in the early summer and "ever-bearing" strawberries, which often bear several crops of fruit throughout the season. Research has shown recently that strawberries actually occur in three basic flowering habits: short-day, long-day, and day-neutral. These refer to the day-length sensitivity of the plant and the type of photoperiod that induces flower formation. Day-neutral cultivars produce flowers regardless of the photoperiod.
Strawberries may also be propagated by seed, though this is primarily a hobby activity, and is not widely practiced commercially. A few seed-propagated cultivars have been developed for home use, and research into growing from seed commercially is ongoing. Seeds (achenes) are acquired either via commercial seed suppliers, or by collecting and saving them from the fruit.
Strawberries can also be grown indoors in strawberry pots.
Kashubian strawberry (truskawka kaszubska or kaszëbskô malëna) are the first Polish fruit to be given commercial protection under EU law. They are produced in Kartuzy, Kościerzyna and Bytów counties and in the municipalities of Przywidz, Wejherowo, Luzino, Szemud, Linia, Łęczyce and Cewice in Kashubia. Only the following varieties may be sold as kaszëbskô malëna: Senga Sengana, Elsanta, Honeoye that have been graded as Extra or Class I.
Advantage of Strawberry
One cup of strawberries contains only 43 calories, has fiber that helps lower blood pressure, and curbs overeating.
Antioxidants
Strawberries contain chemical compounds called phenols. Anthocyanin, a particular phenol abundantly found in strawberries, lends the rich red color to the fruit. Strawberries also contain vitamin C, folate, and the flavonoids, quercetin and kaempferol.
Anti-inflammatory
The phenols in strawberries also fight against many inflammatory disorders, such as osteoarthritis, cancer, asthma and atherosclerosis.
B-complex
The fruit is rich in B-complex group of vitamins. It contains very good amounts of vitamin B-6, niacin, riboflavin, pantothenic acid and folic acid.
Magnificent Manganese
One cup of strawberries contains 21 percent of manganese, an essential nutrient that acts as a powerful antioxidant and anti-inflammatory agent. Manganese is also great for the bones.
Bone Health
Strawberries have potassium, vitamin K, and magnesium— important for bone health
Strawberries are good for your eyes, proper brain function, and provide relief from high blood pressure, arthritis, gout and heart diseases.
Anti-aging properties
Strawberries have biotin, which helps build strong hair and nails. Strawberries also contain the antioxidant ellagic acid, which protects the elastic fibers in our skin to help prevent sagging.
Vigorous Vitamin C
One cup of strawberries contains an incredible 136 percent of the RDA of vitamin C, an effective antioxidant. Vitamin C is vital for connective tissue (collagen) formation, which keeps our skin looking young. Vitamin C has an important role in anti-aging.
Protect Your HeartA Harvard study published in January links eating berries to a lower risk of heart attacks among younger women. The study followed women 25 to 42 who ate more than 3 (1/2-cup) servings of strawberries and/or blueberries each week over an 18-year span. The findings? These women had a 34 percent reduced risk of heart attack compared to those who ate less than one serving per week. Researchers point to the berries’ anthocyanin content as the protective factor. Tip for picking: The reddest berries have the most anthocyanins.
Weight Loss
Strawberries contain a compound called nitrate that has positive effects on blood flow and oxygen around the body. Nitrate stops muscles from becoming too tired after exercise.
Strawberries contain a compound called nitrate that has positive effects on blood flow and oxygen around the body. Nitrate stops muscles from becoming too tired after exercise.
Keep Teeth Healthy
Strawberries are the third-best food source of polyphenols (behind only coffee and olives), according to a 2009 Journal of Dentistry review. That’s good news since researchers believe these compounds inhibit the breakdown of starches in the mouth (thus limiting the resulting sticky sugars that adhere to teeth as plaque) and also fight the bacteria that contribute to tooth decay and gum disease. Scrubbing your teeth with strawberries will whiten them, but because the berries are so acidic, dentists warn that using this home remedy frequently could damage the enamel.
Deliver Your Vitamins
One cup of sliced strawberries provides 163% of your daily dose of vitamin C (more than a whole orange) and 12% Daily Value (DV) of fiber, as well as 9% DV of the B vitamin folate, all for a mere 46 calories. Store berries whole in the refrigerator so they retain the most vitamins or look for berries that have been frozen whole, which preserves more nutrients than slicing or crushing before freezing.
Quell Sugar Spikes
In a recent Finnish study, when healthy women ate white bread with strawberries, their glycemic response to the bread improved by 36 percent over that of subjects who ate just the bread. Researchers explain that components in the strawberries (polyphenols again!) slow the breakdown and absorption of carbs, decreasing the need for insulin to maintain normal blood glucose. And, in another recent study published in the British Journal of Nutrition, when overweight adults consumed either a strawberry beverage or a placebo in combination with a high-carbohydrate meal, the strawberry drinkers showed a significant decrease in the potentially damaging inflammation that typically follows a high-carb meal.
Inhibit Cancer
Research increasingly points to strawberries as an anti-cancer powerhouse, though studies to date have mostly examined strawberry extracts and powders. A study published in November in the International Journal of Cancer showed that strawberry extracts inhibited the growth of lung tumors in mice exposed to cigarette smoke, and a 2012 Chinese clinical trial demonstrated that freeze-dried strawberry powder has potential for preventing esophageal cancer. Strawberries have also been found to be protective against other cancers, including oral, breast and cervical.
Disadvantage of Strawberry
Low in Calories
If you're an athlete or have high calorie needs due to a demanding job or fast metabolism, eating strawberries may be an inefficient way to get the calories you need. A cup of whole strawberries contains just 49 calories, which is much less than other carbohydrate-based foods; a cup of cooked oatmeal provides 147 calories. Because strawberries aren't high in calories, it would take very large portions to obtain significant amounts of calories.
Low in Protein
Strawberries are low in protein, with about 1 g in each cup. Protein is an essential nutrient that your body uses to build and maintain muscles and other tissues. In addition, research indicates that diets with a high ratio of carbohydrates to protein, which is similar to the nutritional profile of strawberries, can be detrimental for body composition. A study published in the March 2011 issue of "Nutrition & Metabolism" found that increasing the ratio of carbohydrates to protein in diets resulted in more energy storage in fat cells and less storage in muscle -- in other words, more fat gain and less muscle gain.
Low in Fat
Strawberries, as with many other fruits, are very low in fat. A cup of strawberries provides less than .5 g of fat. While this keeps the calorie content low, it means that eating strawberries won't be very filling, as fat encourages satiety. Additionally, dietary fat is required for the absorption of some vitamins, so taking a multivitamin with strawberries alone would be less than ideal.
High in Sugar
Strawberries are high in sugar, with 7 g in each cup, an amount comprising 63 percent of the total carbohydrates. While sugar does provide energy, it can also "reactive low blood sugar," or a sugar crash after the initial spike in energy, which can leave you feeling fatigued. Additionally, sugar can promote tooth decay, as this simple carbohydrate forms an acid that attacks your teeth when it comes into contact with the plaque that covers them.
Strawberry Juice
Nutritionist Ronald Prior, who devised the now well-known ORAC (Oxygen Radical Absorbance Capacity), which measures the antioxidant activity in foods, recommends we eat at least 3,500 ORAC units a day to protect from oxidative stress, which contributes to aging. Since strawberries are the fourth highest-rated fruit in ORAC, you can get your 3,500 units in just one and a half cups.
The neuroscientist Jim Joseph was so impressed with these little red berries’ antioxidative power that he decided to research how effective they would be in protecting against the damaging effects of free radical activity in the brain. Since the brain burns glucose for fuel, one of the unwanted byproducts is free radicals, an untold number of them over the course of your lifetime. As we get older, we become more sensitive to their destructive effects. Jim, with the help of Paula Bickfors of the University of Colorado, tested two groups of rats; both were put under extreme oxidative stress by placing them in 100 percent oxygen chambers for 48 hours.
This would mimic the effects of aging on the brain. When the first group was removed and studied, brain activity decreased substantially, equaling aging of between 6 to 18 months. In human years it would be equivalent of going from 18 to 60 years almost overnight. The second group of rats were fed a strawberry-fortified diet for two months prior to the experiment. Incredibly, the second group of rats came out of the oxygen chamber with no change in brain activity. Zero change!
And if that’s not enough, strawberries also contain phenolic acids, one of which is called ellagic acid. This little dynamo has been shown to prevent esophageal and colon tumors in animals. Ellagic acid also encourages cell death in cancer cells. Says Dr. Daniel Nixon, medical oncologist and president of the American Health Foundation in Valhalla New York, “it makes cancer cells learn how to die like normal cells.” Strawberries are also handy if you have to endure second-hand smoke. The ellagic acid neutralizes and dissolves the carcinogen PAH, which is present in cigarette smoke.
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