現在位置 : 飲料 > 牛奶、優酪乳- Milk, Yogurt

牛乳 (Milk, Cow Milk)
     牛乳(俗稱牛奶)是最古老的天然飲料之一。牛乳顧名思義是從雌性乳牛身上所擠出來的。在不同國家，牛乳也分有不同的等級，目前最普遍的是全脂、低脂及脫脂牛乳。美國是牛乳等級分得最仔細的國家，共分有5類，分別是接近無脂(skim milk)、半低脂(0.5 % low fat)、低脂(1 % low fat)、減脂(2 % reduced fat milk)與全脂(whole milk)。目前市面上牛乳的添加物也相當多，如高鈣低脂牛乳，就強調其中增添鈣質。一杯500毫升的全脂牛乳，熱量在300千卡左右。脫脂牛乳脂肪量少於1%以下。
成份
在牛乳中主要包括乳清蛋白與酪蛋白.
(1) 乳清蛋白(whey protein)
(2) 酪蛋白(casein)：主要蛋白質，佔了牛奶蛋白80%，可能會導致一些人腸胃過敏。而β-乳球蛋白與γ-乳白蛋白則只是乳清蛋白的一部分成份.
(3) β-乳球蛋白(beta-lactoglobulin)：可以會導致一些人腸胃過敏，但最具有抗原能力
(4) γ-乳白蛋白(gamma-lactalbumin)

Clover Organic Milk (1 percent)

Milk
       Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of
food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many diseases in the baby. Milk is an important food with many nutrients.
       World's dairy farms produced about 730 million tonnes of milk in 2011. India is the world's largest producer and consumer of milk, yet neither exports nor imports milk. New Zealand, the European Union's 27 member states, Australia, and the
United States are the world's largest exporters of milk and milk products. China and Russia are the world's largest importers of milk and milk products. 
       In the Western world, cow's milk is produced on an
industrial scale and is by far the most commonly consumed form of milk. Commercial dairy farming using automated milking equipment produces the vast majority of milk in developed countries. Dairy cattle such as the Holstein have been bred selectively for increased milk production. About 90% of the dairy cows in the United States and 85% in Great Britain are Holsteins.
    Aside from cattle, many kinds of livestock provide milk used by humans for dairy products. These animals include buffalo, goat, sheep, camel, donkey, horse, reindeer, and yak.​​ The first four respectively produced about 11%, 2%, 1.4 % and 0.2% of all milk worldwide in 2011.

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優酪乳 (Yogurt)
      優酪乳(正式又稱酸乳)是乳製品的一種，由動物乳汁經乳酸菌發酵而產生。優酪乳一詞的英語Yogurt源自土耳其語的
yoğurt，引申自形容詞yoğun，意思是濃稠及豐厚，又或是另一動詞 yoğurmak 意思為「揉、使之濃稠」，都是製作優酪乳的動作和方法。台灣依液態或固態分別譯為「發酵乳」、「優酪乳」或「優格」。香港譯為「乳酪」。中國大陸通稱「酸奶」、「酸奶酪」
定義 --  中國在GB 19302-2010《食品安全國家標準發酵乳》中規定：「酸乳是以生鮮牛（羊）乳或乳粉為原料，經殺菌、接種保加利亞乳桿菌(Lactobacillus delbrueckii subsp. bulgaricus)和嗜熱鏈球菌(Streptococcus thermophilus)發酵製成的產品。」同時還規定了酸乳中的乳酸菌活菌數量大於或等於106cfu/g。
種類 --
 (1) 按生產方法分類
凝固型優酪乳(Set, Plain yogurt)：牛奶在添加生產發酵劑後立即進行灌裝、封口，送入發酵室，產品在包裝容器中發酵而成。
攪拌型優酪乳(Stirred Yogurt)：在發酵罐中接種生產發酵劑。凝固後，再加以攪拌入杯或其它容器內。或添加果料等以豐富其口味。
凍結型優酪乳(Frozen yogurt) 
乳酸飲料(Drinking yogurt /Yogurt drink)：以普通優酪乳為原料，經添加其他非乳成份再行加工製成，濃度一般較稀，流動性好。
(2) 根據脂肪含量高低將優酪乳區分為：高脂優酪乳、全脂優酪乳、低脂優酪乳、脫脂優酪乳等4種。　　
(3) 按健康特性，可分為普通優酪乳和特殊優酪乳，如雙歧優酪乳和益生菌優酪乳。
(4) 根據加入甜味劑與否，還可以分為無糖優酪乳（多加入木糖醇或/和甜蜜素等）和含糖優酪乳。