Modeling and optimization of the parameters affecting extraction of the chan seed mucilage (Hyptis suaveolens (L.) Poit) by mechanical agitation (MA) and ultrasound-assisted extraction (UAE) in a multiple variables system

Abstract

Hydration of the seeds of chan (Hyptis suaveolens (L.) Poit) produces a mucilage that exudes and agglutinates on the surface; the mucilage is difficult to separate from the seed. This study proposes a new strategy for the extraction of hydrated mucilage using the surface response methodology (RSM) and polynomial equations for the optimization of the mucilage extraction by mechanical agitation (MA) and ultrasound-assisted extraction (UAE). The results of the solid:liquid extractions were fitted to a second-order polynomial model for the optimization; the evaluation of the experimental response variables included the yield, viscosity, thixotropy, flow behavior index, consistency coefficient, glass transition temperature, melting temperature, enthalpy and heat capacity. The predicted values of the viscosity, thixotropy, glass transition temperature and melting temperature were significantly different (p < 0.05). The optimal extraction conditions of the mucilage using MA and UAE included the solid:liquid ratios of 1:40 and 1:34.5 with 14.1 and 30 min agitation at 50 and 34.2 °C, respectively. The MA data were compared with the results of UAE and demonstrated that UAE improved certain properties of the mucilage obtained using the optimal extraction conditions proposed by the polynomial models. These conditions enable the use of the mucilage in additional applications in food and pharmaceutical formulations.