Nishimura Kazuhiko, Suzuki Toshiyuki, Itabashi Yutaka
Hokkaido Institute of Public Health: Nishi-12, Kita-19, Kita-ku, Sapporo-shi 060-0819, Japan.
Shokuhin Eiseigaku Zasshi. 2002 Aug;43(4):230-3. doi: 10.3358/shokueishi.43.230.
A highly sensitive HPLC with fluorescence detection was developed for the determination of free fatty acids (FFAs) in milk and dairy products. For this purpose, the FFAs were extracted from small amounts of milk (1.0 mL), cheese (0.5 g) and butter (0.5 g) using Sep-Pak cartridge columns, and then derivatized to 9-anthrylmethyl esters with 9-anthryldiazomethane (ADAM). Good separations of the ADAM derivatives of 16 FFAs (C4-C18) that exist in milk, cheese and butter, which permitted quantitative estimation of their individual FFAs, were achieved by HPLC on a C18 column (Cadenza CD-C18, 150 x 3 mm i.d.) using gradient elution with methanol and water. The acid values calculated from the contents of individual FFAs were in good agreement with those obtained by the conventional titration method. These results demonstrate that the present HPLC method is simple, sensitive and precise, and could be utilized widely for determination of the FFAs in milk and dairy products.
开发了一种用于测定牛奶和乳制品中游离脂肪酸（FFA）的高灵敏度荧光检测高效液相色谱法。为此，使用Sep-Pak柱从少量牛奶（1.0 mL）、奶酪（0.5 g）和黄油（0.5 g）中提取FFA，然后用9-蒽重氮甲烷（ADAM）将其衍生化为9-蒽甲酯。通过在C18柱（Cadenza CD-C18，150×3 mm内径）上使用甲醇和水进行梯度洗脱的高效液相色谱法，实现了牛奶、奶酪和黄油中存在的16种FFA（C4-C18）的ADAM衍生物的良好分离，从而能够对其各自的FFA进行定量估计。根据各个FFA含量计算得到的酸值与通过传统滴定法获得的酸值高度一致。这些结果表明，本高效液相色谱法简单、灵敏且精确，可广泛用于测定牛奶和乳制品中的FFA。
