FOOD SCIENCE ›› 2016, Vol. 37 ›› Issue (22): 28-33.doi: 10.7506/spkx1002-6630-201622005

• Processing Technology • Previous Articles     Next Articles

Optimized Preparation of Laccaic Acid Ester Using Orthogonal Array Design

LIU Lanxiang, PU Zhenqi, ZHENG Hua, XU Juan, LI Kun, ZHANG Hong*   

  1. Research Center of Engineering and Technology on Forest Resources with Characteristics, State Forestry Administration, Research Institute of Resources Insects, Chinese Academy of Forestry, Kunming 650224, China
  • Received:2016-04-29 Online:2016-11-16 Published:2017-02-22

Abstract: Laccaic acid is one of the most valuable shellac products and improvement of its solubility is a strong impetus for its development and utilization. In this study, laccaic acid ester was prepared from laccaic acid by two sequential reactions, namely esterification with methanol and acylation with acetic anhydride. The reaction conditions were optimized using one-factor-at-a-time method and orthogonal array design as follows: 36 h estertification of 1.0 g of laccaic acid in the presence of 5.0% (relative to laccaic acid) p-toluenesulfonic acid, and acylation with 1.0 mL of acetic anhydride in the presence of 2.5 mL of triethylamine. Under these conditions, the esterification rate reached 81.3% with standard deviation (SD) of 0.67%. The presence of ester and alkyl groups in the obtained product was confirmed by FTIR and UV-Vis spectroscopic analyses. The melting temperature of the laccaic acid ester was 68 ℃ as demonstrated by DSC analysis, and temperature higher than 198 ℃ caused its decomposition. The color value of the laccaic acid ester was 121. It could be dissolved in most organic solvents, especially oils. Its solubility in rapeseed oil reached 0.340 g/L, and the oil sample was red in color and remained clear without precipitation after 28 d of storage, with a retention rate of 96.2%. The laccaic acid ester was proven to have good stability and solubility indicating its promising application potential.

Key words: laccaic acid, laccaic acid ester, orthogonal array design, liposolubility

CLC Number: