min'cellanea

紐西蘭ViaLactia 公司的科學家發現乳牛(Friesian cow)中的一個突變基因可以使牠所生產的牛奶中的飽和脂肪大量減低，但卻含有豐富的omega-3，而由它所製成的奶油可以像人工奶油(margarine)一樣直接塗抹使用。

此頭母牛現命名為Marge，於2001年發現，ViaLactia 的科學家以$300 紐幣從飼主那裡買下來，已開始大量繁殖其含有此突變基因的後代。Marge 的後代中約有一半含有此突變基因，顯示此為顯性遺傳，但科學家還不知道產生此低脂牛奶的確切機制為何。



Russell Snell, ViaLactia's chief scientist, said: "Marge looks like an ordinary Friesian cow but has three key differences. She produces a normal level of protein in her milk but substantially less fat, and the fat she does produce has much more unsaturated fat. She also produces milk with very high levels of omega3 oils." -- TIMES ONLINE

Marge 和其他平常的Friesian 牛種外觀一樣，但是有三個主要的不同點：牠所產生的牛奶含有正常量的蛋白質，但脂肪卻比正常量少很多，而且其脂肪多為不飽和脂肪，牠的牛奶也含有大量的omega-3。

"Government health campaigns now push low-fat diets and sales of whole milk, which contains 3.5% butter fat, account for just 25% of milk sales. By contrast, sales of semi-skimmed milk, which contains 1.7% fat, and skimmed milk, which has 0.1% fat, account for 75% of sales. The New Zealand animals are understood to have less than 1% fat in their milk." -- TIMES ONLINE

全脂牛奶含有3.5% butter fat，低脂奶含1.7% fat，脫脂奶為0.1% fat，紐西蘭Marge 所產的奶少於1% fat。

此研究成果將於這週的英國期刊Chemistry & Industry 中發表。

"The Auckland-based company says the first commercial herds for spreadable butter could be expected by 2011."



【minc 說】傑克，這真是太神奇啦～



相關新聞

[Stuff.co.nz] Skim milk straight from green-top cows
[CBC.ca] Will that be a low fat or regular cow?
[TIMES ONLINE] Scientists breed cows that give skimmed milk


Reference

[Genome News Network] Scientists pinpoint gene linked to fat in cow's milk

Grisart B. & Coppieters W. et al. Positional Candidate Cloning of a QTL in Dairy Cattle: Identification of a Missense Mutation in the Bovine DGAT1 Gene with Major Effect on Milk Yield and Composition. Genome Research (2002) 12, 222-231.