現在位置 : 水果 > 蘋果 - Apples - (水果之王)
蘋果 (Apple)
蘋果 (學名:Malus domestica)是薔薇科蘋果亞科蘋果屬植物,落葉喬木。蘋果的果實富含礦物質和維生素,為人們最常食用的水果之一。落葉喬木,樹高可達15米,栽培條件下一般高3~5米。樹榦灰褐色,老皮有不規則的縱裂或片狀剝落,小枝光滑。葉序為單葉互生,橢圓至卵圓形,葉緣有鋸齒。傘房花序,花瓣白色,含苞時帶粉紅色,雄蕊20,花柱5,大多數品種自花不育,需種植授粉樹。果實為仁果,顏色及大小因品種而異。蘋果膳食纖維含量很豐富,也含有大量的果膠,對於整腸及調整腸道菌叢生態大有幫助。是一種綠色水果。蘋果樹木喜光,喜微酸性到中性土壤。最適於土層深厚,富含有機質,心土通氣排水良好的沙質土壤。 蘋果品種 蘋果有超過7,500個已知品種。良種有紅星系列、紅富士、喬納森等。美國的名種有Red Delicious (香港稱地利蛇果,簡稱蛇果;台灣稱五爪蘋果)、Gold Delicious等。英國北威爾斯巴德西島(Bardsey Island)則在近年發現新品種,比普通的果樹更健康,除了蟲害以外,並不會患病,被媒體稱為「世界上最罕有的蘋果」。除鮮食的品種外,尚有烹飪用的蘋果。由於蘋果的果酸有保持水份的作用,適宜焗烤。 蘋果營養 蘋果含有大量的果膠,這種可溶性纖維質可以降低膽固醇及壞膽固醇的含量。一中等大小未削皮的蘋果可提供3.5克的纖維質(即使削了皮,也含2.7克的纖維質),是營養專家建議的每日攝取量的百分之10以上,而且僅含80卡路里的熱量。《美國生理學期刊》的研究指出,在深紅色的生果皮,如蘋果及提子等,均驗出有Resveraltrol。該物質可減少呼吸系統包括氣管及肺部等的發炎,從而控制哮喘及慢性阻塞性肺炎等病症。 蘋果中的果膠和鞣酸有收斂作用,可將腸道內積聚的毒素和廢物排出體外。其中的粗纖維能鬆軟糞便,利於排泄;有機酸能刺激腸壁,增加蠕動作用;而維生素C更有效保護心血管。蘋果皮中富含多酚,多酚含有極佳的抗氧化作用,有助於抗老防癌。 |
Apple Nutrition
The proverb "An apple a day keeps the doctor away.", addressing the health effects of the fruit, dates from 19th century Wales. Preliminary research suggests that apples may reduce the risk of colon cancer, prostate cancer and lung cancer. Apple peels contain ursolic acid which, in rat studies, increases skeletal muscle and brown fat, and decreases white fat, obesity, glucose intolerance, and fatty liver disease. According to the United States Department of Agriculture, a typical apple serving weighs 242 grams and contains 126 calories with significant dietary fiber and vitamin C content. Apple peels are a source of various phytochemicals with unknown nutritional value and possible antioxidant activity in vitro. The predominant phenolic phytochemicals in apples are quercetin, epicatechin, and procyanidin B2. Apple juice concentrate has been found in mice to increase the production of the neurotransmitter acetylcholine. Other studies have shown an "alleviation of oxidative damage and cognitive decline" in mice after the administration of apple juice. Fruit flies fed an apple extract lived 10% longer than other flies fed a normal diet. Popular Uses of Apple Apples are an important ingredient in many desserts, such as apple pie, apple crumble, apple crisp and apple cake. They are often eaten baked or stewed, and they can also be dried and eaten or reconstituted (soaked in water, alcohol or some other liquid) for later use. Puréed apples are generally known as apple sauce. Apples are also made into apple butter and apple jelly. They are also used (cooked) in meat dishes. In the UK, a toffee apple is a traditional confection made by coating an apple in hot toffee and allowing it to cool. Similar treats in the US are candy apples (coated in a hard shell of crystallized sugar syrup), and caramel apples, coated with cooled caramel. Sliced apples turn brown with exposure to air due to the conversion of natural phenolic substances into melanin upon exposure to oxygen. Different cultivars vary in their propensity to brown after slicing. Sliced fruit can be treated with acidulated water to prevent this effect. |