油脂依其來源可分為動物性油脂與植物性油脂，油脂皂化價受油脂脂肪酸碳鏈長度影響，因此油脂種類決定皂化產物之特性與質感，不同的油脂達成皂化反應所需時間也各有差異。本試驗之目的係研究不同來源油脂對於皂化作用之影響以及皂化產物之物化特性變化；本試驗分別選用常見於畜牧產品之動物性油脂：乳脂、豬脂及雞脂；以及飼糧常用添加之大豆油作為原料。油脂經加熱處理之後添加適當比例氫氧化鈉溶液誘發皂化作用之進行，待長時間皂化反應完全後，分別針對皂化產物之溶解度、酸鹼值、起泡能力、油滴分解率以及耗費之價格成本進行分析。初步結果得知乳脂、豬脂、雞脂與大豆油之皂化能力並無顯著差異，乳脂組之皂化產物質地堅硬而厚實、產生之泡沫溫和而穩定，豬油組質地較乳脂組軟且在冷水條件下洗滌效果不佳，而大豆油組泡沫持久。

關鍵語：皂化價、脂肪酸

H.L. Lin, Y.C. Huang, M.C. Wu

Livestock Research Institute, Council of Agriculture

The lipid may divide into the animal fat and the vegetable oil according to its origin, and the saponification value affected by the carbon chain length of fatty acids. The types of lipid determine the properties of saponification products. Besides, it takes different time to accomplish the reactions of saponification by the different lipid. The objective of this study was to research the effect of the saponification and the physical and chemical variations of saponification products from different lipid. We selected butter, lard and chicken fat, which are the common animal fat in the livestock, and soybean oil, commonly used in feedstuff. After the heating process, added the appropriate proportion of sodium dioxide solution to induce saponification. After the reaction of saponification completed for a long time, we analyzed the solubility, pH value, frothing ability, the oil dripping rate of dissociation and cost of saponification products. The preliminary result showed that there was no significant difference on the time to accomplish the saponification among butter, lard, chicken fat and soybean oil. The properties of saponification products of butter group were hard and thick, and the froth was mild and stable. The lard group was softer than butter group, and it was not fine to use under cold water. The froth of soybean oil group was lasting.

Key words: Saponification value, Fatty acid