Ultrasound-assisted extraction of Psyllium mucilage: evaluation of functional and technological properties

Abstract

The objective of this work was to optimize the extraction of psyllium mucilage and to evaluate its functional and technological properties, aiming for the first time the use in ice cream. A factorial design was carried out to test different extraction conditions. Were evaluated the water solubility (WS) and oil absorption capacity. Mucilage (gel and dried) was applied in ice cream, and submitted to overrun, melting, color and sensory analysis. Time and temperature were significant parameters, being the best conditions at 60ºC for 2 hours. Samples presented WS between 200 and 1400 g/kg, increasing proportionally to temperature. Ice cream with gel presented higher value and started the melting process faster than the mucilage one. There was a significant difference between samples in flavor, color and texture, and the purchase intention of most tasters indicated "maybe would buy", and both ice cream (with gel and with mucilage) presented hight acceptance index. Psyllium presented good technological properties, that are very desirable in food products. It was possible to find the best condition for psyllium mucilage extraction and an ice cream application obtaining a product with good acceptance (82%).