生產二酸甘油酯(DG)在食品、藥劑及化妝品工業中扮演重要角色。尤其是DG可以做為生產母乳脂肪替代物之起始基質。本研究找出 以無觸媒、兩步驟法生產1,3（-2） - 二醇基-2（-1）- 棕櫚基甘油酯之最適化條件。探討在氮氣環境下，反應時間8小時，溫度(150°C, 175°C, 200°C)、油酸對甘油莫爾比(1:1, 2:1, 3:1, 4:1)及起始水含量對DG選擇性(g DG/g MG+TG)以及油酸轉化率之影響。結果發現初始水含量對反應速率及產物選擇性無顯著影響；以分子篩去除初始含水後對結果亦無顯著影響。在最佳條件下(200°C、莫爾比1:1、反應 8 小時)，可得到DG 含量及選擇率分別為56.61±3.06% 及1.30 (g DG/g MG+TG)。此粗產物再與棕梠酸在不同溫度(175°C, 200°C, 225°C)及棕梠酸對DG莫爾比 (1:1, 1.5:1, 2:1, 2.5:1)下行酯化反應。在溫度 225°C 、莫爾比 2:1，反應2小時可得平衡OOP/OPO 選擇率41.89±0.21% (g OOP(OPO)/ g TG)。 與催化反應比較，本研究陰部使用觸媒，不會產生皂化反應，是以下游處理較簡單。雖然本研究使用較高反應溫度，但所需要反應時間較短。

Production of diglycerides (DGs) plays an important role in the food, pharmaceutical, and cosmetic industries. Particularly, they can be used as starting materials for the production of human milk fat substitutes(HMFS). In this study, optimal conditions for the non-catalyzed production of 1,3(-2)-dioloeyl-2(-1)-palmityl glyceride were determined. A two-step non-catalyzed esterification was done. The temperature (150°C, 175°C, 200°C), oleic acid to glycerol molar ratio (1:1, 2:1, 3:1, 4:1), and initial water content were varied to determine DG selectivity (g DG/g MG+TG) and % conversion (with respect to oleic acid) over an 8 h period in a nitrogen-purged system. It was also noted the tested initial water contents showed insignificant effect on reaction rates and product selectivity. Addition of molecular sieves for removal of water also demonstrated negligible effects in this temperature range. Diglycerides production was optimized at 200°C and 1:1 molar ratio at 8 hours resulting in a DG content of 56.61±3.06% and a selectivity of 1.30 (g DG/g MG+TG), respectively. The crude product was then esterified with palmitic acid at varying temperatures (175°C, 200°C, 225°C) and palmitic acid to DG in crude product molar ratios (1:1, 1.5:1, 2:1, 2.5:1). Equilibrium OOP/OPO selectivity (g OOP(OPO)/ g TG) of 41.89±0.21% was obtained at a molar ratio of 2:1 and a temperature of 225°C for 2h. Compared to catalyzed reactions, this system would require less downstream procedures as no catalysts need to be removed and no saponification would occur. Although this procedure involves higher reaction temperature compared to enzyme-catalyzed reactions, the time required to obtain high conversion is much shorter.

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