本研究以玉米澱粉為反應基質，與不同碳數脂肪酸、不同油種分別於與澱粉酯化反應，並且以化學法與酵素法進行酯鍵合成，可得脂肪酸修飾澱粉(fatty acid modified starch, FAMS)。後續對產物性質探討的試驗中，首先以鹼水解滴定法測定FAMS之取代度，並以FTIR圖譜辨別澱粉與脂肪酸之間酯鍵的生成，接著測定FAMS之熱性質、接觸角與抗性澱粉含量。結果顯示，取代度隨著脂肪酸碳數增加而跟著增加且脂肪酸雙鍵越多其取代度也越多，而含有較多雙鍵的花生油具有較高的取代度。相較於玉米澱粉，所有的FAMS在FTIR圖譜1730-1750 cm-1亦產生新的吸收峰，直接證實澱粉與脂肪酸的酯鍵生成。由接觸角測量的結果可知，FAMS錠片與蒸餾水探針的接觸角大於澱粉粒與澱粉溶出物，表示酯化修飾提升了澱粉的疏水性。由DSC可看出FAMS的玻璃轉移溫度與玉米澱粉比較，其溫度下降，表示其熱塑性變佳。接著，可以看到隨著取代度的增加其抗性澱粉的含量也明顯提升。 Starch esterification was proceeded with corn starch and several fatty acids. The fatty acid modified starch (FAMS) was prepared by using chemical method and Enzyme method. To characterize FAMS, the degree of substitution (DS) of FAMS was determined by alkaline titration methods and the ester bonds formed between hydroxyl groups of corn starch and carboxyl groups of atty acids were confirmed by FTIR. The thermal properties of FAMS were also investigated by using DSC. The surface polarity of FAMS was assessed by the contact angle measurement. The resistant starch(RS) value was examined by RS Assay kit. FAMS was modified with the fatty acid more carbons had higher DS value, and the fatty acid with double bond had higher DS value than the one without double bond. Then we can perceive peanut oil have highest DS value than the others since peanut oil is composed of much linoleic acid has two pair of double bond. Comparing with corn starch, FAMS had new absorbance at 1730-1750 cm-1 in FTIR spectra, which confirmed the ester bonds formed between hydroxyl group of starch and carboxyl group of fatty acid. The results of contact angle measurements revealed that FAMS was more hydrophobic than corn starch. The results of DSC show that FAMS was more thermoplastic than corn starch. In the end, The increases of DS value and increases of RS value were found in FAMS.
