Microcapsules with dodecanol (C12OH) encapsulated were prepared through complex coacervation by adding gelatin (GE) solution to an acacia gum (AG) solution and through GE simple coacervation by adding sodium sulfate solution to GE solution

both in presence of C12OH.C12OH was chosen for the core material because it does constitute a real component in sex pheromones of numerous insects.In a first step

Zeta potential and light transmittance in the two coacervation processes were followed in order to determine the optimum ratio of AG and GE in complex coacervation and the best amount of sodium sulfate in simple coacervation.It was observed that maximum yield was achieved for complex coacervation with AG/GE weight ratio at unity

and for simple coacervation when 30 mL of 20% sodium sulfate was added to 40 mL of 6% GE solution.When the wall material concentration was equal to or higher than 3%

the size of the microcapsules from complex coacervation was larger than that prepared through simple coacervation.Nevertheless

simple coacervation led to capsules with much narrower size distribution.C12OH encapsulation rates in simple coacervation were significantly lower compared with those in complex coacervation at equal wall material concentration

leading therefore to a lower C12OH loading in simple coacervation.To investigate C12OH release from the capsules

samples were placed into an incubator with constant temperature (30℃) and relative humidity (50% RH)

and taken out for C12OH examination by gas chromatography and by weighing the samples.It was found that all samples from simple coacervation reached their final release in less than one week

no difference was observed for samples prepared with different wall material concentration; whereas microcapsules from complex coacervation manifested a three_step_release profile

i.e.a quick start followed by a constant plateau region and terminated by a release increase till completion.Results also revealed that capsules prepared with higher wall material concentration had a higher release rates.The capsules prepared with 5% solutions of AG and GE lost their C12OH within 2 weeks; lowering wall material concentration effectively reduced C12OH release rate and extended C12OH constant release period.This work indicates that release of C12OH can be well controlled through capsule structure designing.This is of great importance for our on_going study on controlled release of authentic insect semiochemicals.