在植物性起酥油中使用的棉籽油
The Use of Cottonseed Oil in Vegetable Shortenings
作者： C. Clay King食品營養系助理教授，得克薩斯女子大學，丹頓。德克薩斯州。
資料來源：轉載自全球穀物食品Reprinted from Cereal Foods World. http://www.cottonseed.com/publications/Use%20of%20Cottonseed%20Oil%20in%20Vegetable%20Shortenings.pdf
在1860年代和1870年代的美國，最早食用棉籽油是用來煉豬油和橄欖油混合沙拉油。The first edible uses of cottonseed oil were to temper lard and to blend with olive oil for salad oils during the 1860s and 1870s (I). 在1880年代，由於意大利的進口稅導致減少出口棉籽油至意大利，使在美國使用棉籽油、豬油混合油的價格戲劇性的下跌，。In the 1880s, the use of cottonseed oil in lard compounds in the United States increased dramatically as the price of the oil dropped due to an Italian import duty that reduced exports of cottonseed oil to that country. 另外，在這個時候，棉籽油是第一次使用在人造奶油。Also during this time. cottonseed oil was first used in margarine. 恰逢這些商業用途，以改良精進的壓榨和精煉棉籽油的方法，製造出高品質、純淨，更便宜的油。Coinciding with these commercial uses were improved crushing and refining methods resulting in a high quality. pure, and less expensive oil.
最終，以氫化棉籽油用來增加棉籽油做為酥油和人造奶油的可塑性，以氫化棉籽油取代高濃度棉子油做為酥油來增加油炸食品的軟Q度。Eventually, hydrogenation was used to increase the plasticity of cottonseed oil in shortenings and margarines to overcome the increased softness of products with high levels of cottonseed oil. 在1903年，W.諾曼先生（W. Normann）取得液相氫化植物油的英國專利。In 1903. a British patent was issued to W. Normann for liquid-phase hydrogenation of vegetable oils. 這項液相氫化植物油專利被瓷磚英國公司的約瑟夫·克羅斯和兒子（tile British firm of Joseph Crossfield a nd Sons）收購。1909年Procter and Gamble購得美國生產權。This patent was acquired by tile British firm of Joseph Crossfield a nd Sons. from which Procter and Gamble bought the U.S. production rights in 1909. 在1911年，完全由氫化棉籽油製成的固體脂肪命名Crisco，成為上市的一個高品質酥油。In 1911, a solid fat called Crisco. made entirely from hydrogenated cottonseed oil. was place on the market as a high-quality shortening (I).
選擇性氫化棉籽油的亞油酸到油酸比增加固體脂肪的百分比。並提高了棉籽油的熔點和穩定性。Selective hydrogenation of cottonseed oil linoleate to oleate increased the percent solids,. raising the melting point and increasing stability. 然後加入高度氫化比率的棉籽油，以進一步提高固體脂肪可塑性和固體脂肪指數（SFI）。Then a highly hydrogenated portion was added to further increase the plasticity and Solid Fat Index( (SFI)。 高度氫化棉籽油使油品更穩定，及更寬廣的可塑性範圍。 resulting in a more stable product with a wider plastic range.因此，高度氫化棉籽油製成的固體脂肪Crisco的乳化能力等於或優於豬油的一個好產品。Thus. Crisco was a better product which had a creaming ability equal to or greater than that of lard. 直到1940年代，當大豆和其他油源開始增加生產，棉籽植物起酥油主宰植物起酥油的市場。Cottonseed vegetable shortening dominated the market until the 1940s, when the production of soybean and other oil sources began to Increase.
在1965年至1985年期間，平均每人消耗在烘焙和油炸的棉籽植物起酥油脂肪從每人14.2磅，增加到22.9磅。Per capita consumption of shortening classified as baking and frying fats increased from 14.21b per person to 22.9 Ib during the period of 1965-1985 (2). 在同一時間，過去用做烘焙和油炸的豬油和食用牛脂肪，平均每人減少消耗2.6磅。At the same time, consumption of the lard and edible beef tallow, historically used as baking and frying fats, decreased by 2.6 Ib per capita. 在美國飲食1985年，棉籽植物起酥油佔36％可見到的脂肪消耗。In 1985, shortening accounted for 36% of the visible fat consumed in,U.S. diets。
氫化植物油 → 反式脂肪 → 特性卻較接近飽和脂肪→ 增加血中的壞膽固醇 → 冠心病。
我們從食物攝取反式脂肪的主要來源是以氫化植物油製成的食物。植物油經過氫化過程後，
會由液體轉化為半固體或固體，而反式脂肪亦會同時形成。氫化程度愈高，油會愈接近固體。理論上，完全氫化的油不應含有反式脂肪，因為所有雙鍵均已飽和，但這種油卻會變硬。由於氫化植物油能延長食品的保質期，改善口感，而且通常成本較低，故常用於生產或配製烘焙或油炸食物。
反式脂肪屬於不飽和脂肪，當中有一個或以上的碳雙鍵是反式排列，因而有別於其他不飽和脂肪。不過，其特性卻較接近飽和脂肪。飽和脂肪會增加血液中的壞膽固醇（又稱為低密度脂蛋白膽固醇），是冠心病的已知風險因素。
以每天攝取2 000千卡熱量的人為例，反式脂肪、飽和脂肪及總脂肪的每天攝取量應少於2.2克、22.2克及66克。
資料來源：
http://www.cfs.gov.hk/sc_chi/food_leg/files/trans-fats-guide-c.pdf
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