Optimization of the antioxidant capacity of thyme (Thymus vulgaris L.) extracts: Management of the drying process

The antioxidant properties of medicinal plants have been at the center of research for their use as preservatives or nutraceuticals by the food industry; additionally, to obtain quality products at a minimum cost and maximum yield, through optimal operating parameters, is a challenge for the food industry. The aims of this work was to effect operating conditions drying process on antioxidant capacity of the thyme and optimize the drying process creating a process management system to formulate and solve an optimization problem. The thyme drying process was analyzed under different drying air temperatures (T) (40-80 degrees C) and drying air velocity (V) (1-2 m/s). The essential oil was extracted by applying a super-critical fluid extraction method (35 degrees C, 35 x 10(3) kPa). To formulate and solve the optimization problem, artificial neural networks were developed. The optimum value of the optimization problem depend of the constraints established, shorting the drying time to research the final moisture content fixed. (C) 2013 Elsevier B.V. All rights reserved.