歐禮莎侓 - Olisalud 大家一起瘋橄欖

摘選自Olive oil consumption and non-alcoholic fatty liver disease

作者：Assy N, Nassar F, Nasser G, Grosovski M
Liver Unit, Ziv Medical Centre, Safed, Israel. assy.n@ziv.health.gov.il

每100克橄欖油含有下列脂肪酸：

l      單元不飽和脂肪酸（MUFAs ，N - 9油酸18:1）73.7克

l      飽和脂肪酸（SFA，saturated fatty acids）-16:0棕櫚酸（palmitic acid）13.5克

l       多元不飽和脂肪酸（PUFA); polyunsaturated fatty acids）7.9克（ n - 6亞油酸 18:2，和n - 3α-亞麻油酸18:3）。

單元不飽和脂肪酸（MUFAs）包括：

l       十六酸（palmitic acid，C16：1）

l       油酸（oleic acid，C18：1 9c）、

l       反式油酸（elaidic acid，C18：1 9t）(油酸與硝酸作用，異構化為反式異構體，及反式油酸)

l       反–11–烯十八酸（vacentic acid，C18：1 11t）。

含有最豐富的單元不飽和脂肪酸的飲食是油酸（C18：1的N - 9）。在地中海國家，單元不飽和脂肪酸的主要來源是橄欖油（74 g/100克）。其他食用油中含單元不飽和脂肪酸的比例分別為：菜油（59 g/100克），花生油（46 g/100克），葵花油（32 g/100克），玉米油（29 g/100克），黃豆油（24 g/100克）和藏紅花油（14 g/100克）。此外，新款的食用油已經改變配方，包括像是高油酸葵花籽油（84 g/100 g）以及高油酸紅花油（74 g/100克）都已發展成具有豐富的油酸。除了高含量的單元不飽和脂肪酸，初榨（未精緻）橄欖油含有大量的抗氧化劑和α-維生素 E和植物化學物質。然而，當精緻過或加熱過後，橄欖油失去這些天然化合物。

橄欖油根據油酸值（酸價）作分級。初榨橄欖油，即第一次壓製而得之產品，具有最大的自由酸度（意即油酸，oleic acid)，包含豐富的角鯊烯和酚類抗氧化劑，諸如純酚類（水合酪氨酸，酪醇），醛環烯醚萜，黃酮類和木脂素（乙酰松脂醇，松脂醇二）。有趣的是，跟精製過的橄欖油和種子油相比，它明顯的含有更高濃度的酚類抗氧化劑和角鯊烯。此外，一般種子油中不但角鯊烯的含量非常低，更沒有酚類抗氧化劑。橄欖油的實際化學成分不僅取決於採收當年的生長條件，果實的成熟度以及（冷壓，精煉）壓製技術也有關係。

同篇報導其他續文 -

1. 食用橄欖油對非酒精性脂肪肝的影響
2. 橄欖油(對改善非酒精性脂肪肝)的特別機制

文章來源：美國國家醫學圖書館，國家衛生研究院

上述原文請詳下方或連結http://www.ncbi.nlm.nih.gov/pubmed/19370776

Each 100 g of olive oil contains the following fatty acids: MUFA 73.7 g (n-9 oleic acid 18:1); saturated fatty acids (SFA) 13.5 g (16:0 palmitic acid); polyunsaturated fatty acids (PUFA) 7.9 g (n-6 linoleic acid 18:2, and n-3 alpha-linoleic acid 18:3)[¹⁴].

MUFAs include palmitic (C16:1), oleic (C18:1), elaidic (C18:1) and vacentic acids (C18:1). The most abundant MUFA in the diet is oleic acid (C18:1 n-9)[¹⁵]. In Mediterranean countries, the main source of MUFA is olive oil (74 g/100 g). Other oil sources of MUFAs are canola (59 g/100 g), peanut (46 g/100 g), sunflower (32 g/100 g), corn (29 g/100 g), soybean (24 g/100 g) and safflower oils (14 g/100 g)[¹⁶]. Additionally, new oil variants, rich in oleic acid have been developed including high-oleic acid sunflower oil (84 g/100 g) and high oleic acid safflower oil (74 g/100 g)[¹⁷]. In addition to a high MUFA content, virgin (unrefined) olive oil contains a significant amount of antioxidants and α-tocopherol and phytochemicals. However, when refined or heated, olive oil loses these natural compounds[¹⁸].

Olive oil is graded according to its acidity. Extra virgin olive oil, the first pressed oil, having maximum free acidity, contains an abundance of squalene and phenolic antioxidants including simple phenols (hydroxytyrosol, tyrosol), aldehydic secoiridoids, flavonoids and lignans (acetoxypinoresnol, pinoresinol). Interestingly, it contains significantly higher concentrations of phenolic antioxidants and squalene than refined virgin and seed oils. In addition, seed oils, which contain very low amounts of squalene, have none of the phenolic antioxidants that are present in virgin and refined olive oils[¹⁹]. The exact composition of olive oil depends not only on the growth conditions in the year preceding the harvest, but also on the degree of ripeness of the fruit and the technical processing (cold pressing, refining)[²⁰].